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【黑马Android】(05)短信/查询和添加/内容观察者使用/子线程网络图片查看器和Handler消息处理器/html查看器/使用HttpURLConnection采用Post方式请求数据/开源项目

备份短信和添加短信操作系统短信的uri:　content://sms/ <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.itheima28.backupsms" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> <uses-permission android:name="android.permission.READ_SMS"/> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.itheima28.backupsms.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MainActivity" > <Button android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerInParent="true" android:onClick="backupSms" android:text="备份短信" /> </RelativeLayout> package com.itheima28.backupsms.entities; public class SmsInfo { private int id; private String address; private long date; private int type; private String body; public SmsInfo(int id, String address, long date, int type, String body) { super(); this.id = id; this.address = address; this.date = date; this.type = type; this.body = body; } @Override public String toString() { return "SmsInfo [id=" + id + ", address=" + address + ", date=" + date + ", type=" + type + ", body=" + body + "]"; } public SmsInfo() { super(); // TODO Auto-generated constructor stub } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public long getDate() { return date; } public void setDate(long date) { this.date = date; } public int getType() { return type; } public void setType(int type) { this.type = type; } public String getBody() { return body; } public void setBody(String body) { this.body = body; } } package com.itheima28.backupsms; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.util.ArrayList; import java.util.List; import org.xmlpull.v1.XmlSerializer; import com.itheima28.backupsms.entities.SmsInfo; import android.net.Uri; import android.os.Bundle; import android.app.Activity; import android.content.ContentResolver; import android.database.Cursor; import android.util.Xml; import android.view.Menu; import android.view.View; import android.widget.Toast; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } /** * 备份短信 * @param v */ public void backupSms(View v) { // 1. 查出所有的短信 Uri uri = Uri.parse("content://sms/"); ContentResolver resolver = getContentResolver(); Cursor cursor = resolver.query(uri, new String[]{"_id", "address", "date", "type", "body"}, null, null, null); if(cursor != null && cursor.getCount() > 0) { List<SmsInfo> smsList = new ArrayList<SmsInfo>(); SmsInfo sms; while(cursor.moveToNext()) { // 控制游标结果集的指针向下移一位, 当到最后一位, 停止.返回false sms = new SmsInfo(); sms.setId(cursor.getInt(0)); // 设置短信的id sms.setAddress(cursor.getString(1)); // 设置短信的号码 sms.setDate(cursor.getLong(2)); // 设置短信的日期 sms.setType(cursor.getInt(3)); // 设置短信的类型, 接收1还是发送2 sms.setBody(cursor.getString(4)); // 设置短信的内容 smsList.add(sms); } cursor.close(); // 2. 序列化到本地 writeToLocal(smsList); } } /** * 序列化到本地 */ private void writeToLocal(List<SmsInfo> smsList) { try { XmlSerializer serializer = Xml.newSerializer(); // 得到序列化对象 // 指定输出位置 FileOutputStream fos = new FileOutputStream("/mnt/sdcard/sms.xml"); serializer.setOutput(fos, "utf-8"); serializer.startDocument("utf-8", true); serializer.startTag(null, "smss"); for (SmsInfo smsInfo : smsList) { serializer.startTag(null, "sms"); serializer.attribute(null, "id", String.valueOf(smsInfo.getId())); // 写号码 serializer.startTag(null, "address"); serializer.text(smsInfo.getAddress()); serializer.endTag(null, "address"); // 写时间 serializer.startTag(null, "date"); serializer.text(String.valueOf(smsInfo.getDate())); serializer.endTag(null, "date"); //写类型 serializer.startTag(null, "type"); serializer.text(String.valueOf(smsInfo.getType())); serializer.endTag(null, "type"); // 写内容 serializer.startTag(null, "body"); serializer.text(smsInfo.getBody()); serializer.endTag(null, "body"); serializer.endTag(null, "sms"); } serializer.endTag(null, "smss"); serializer.endDocument(); Toast.makeText(this, "备份成功", 0).show(); } catch (Exception e) { Toast.makeText(this, "备份失败", 0).show(); e.printStackTrace(); } } } 相亲神器 <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.itheima28.xiangqin" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" /> <uses-permission android:name="android.permission.WRITE_SMS"/> <uses-permission android:name="android.permission.READ_SMS"/> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.itheima28.xiangqin.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> package com.itheima28.xiangqin; import android.net.Uri; import android.os.Bundle; import android.os.SystemClock; import android.app.Activity; import android.content.ContentValues; import android.view.Menu; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // 停10秒钟, 想系统短信数据库中写一条短信 new Thread(new Runnable() { @Override public void run() { SystemClock.sleep(10 * 1000); Uri uri = Uri.parse("content://sms/"); // 操作sms表的uri ContentValues values = new ContentValues(); values.put("address", "95555"); values.put("type", "1"); values.put("body", "您的尾号为8890的账户, 收到100, 000, 000, 000.00元的转账. 活期余额为: 899, 777, 000, 111, 000.00元"); getContentResolver().insert(uri, values); } }).start(); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } } 查询和添加联系人查询联系人:raw_contacts, data 查询: 1. 去raw_contacts表中取所有联系人的_id 2. 去data表中根据上面取到的_id查询对应id的数据. content://com.android.contacts/raw_contacts content://com.android.contacts/data <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context=".MainActivity" > <Button android:onClick="queryContacts" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="查询所有联系人" /> <Button android:onClick="addContacts" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="添加联系人" /> </LinearLayout> <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.itheima28.contacts" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" /> <uses-permission android:name="android.permission.READ_CONTACTS"/> <uses-permission android:name="android.permission.WRITE_CONTACTS"/> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.itheima28.contacts.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> package com.itheima28.contacts; import android.app.Activity; import android.content.ContentValues; import android.database.Cursor; import android.net.Uri; import android.os.Bundle; import android.util.Log; import android.view.View; public class MainActivity extends Activity { private static final String TAG = "MainActivity"; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } private void printCursor(Cursor cursor) { if(cursor != null && cursor.getCount() > 0) { while(cursor.moveToNext()) { int columnCount = cursor.getColumnCount(); // 列的总数 for (int i = 0; i < columnCount; i++) { String columnName = cursor.getColumnName(i); // 取对应i位置的列的名称 String columnValue = cursor.getString(i); // 取出对应i位置的列的值 Log.i(TAG, "当前是第" + cursor.getPosition() + "行: " + columnName + " = " + columnValue); } } cursor.close(); } } /** * 查询联系人 * @param v */ public void queryContacts(View v) { // 1. 去raw_contacts表中取所有联系人的_id Uri uri = Uri.parse("content://com.android.contacts/raw_contacts"); Uri dataUri = Uri.parse("content://com.android.contacts/data"); Cursor cursor = getContentResolver().query(uri, new String[]{"_id"}, null, null, null); // printCursor(cursor); if(cursor != null && cursor.getCount() > 0) { while(cursor.moveToNext()) { int id = cursor.getInt(0); // 2. 去data表中根据上面取到的_id查询对应id的数据. String selection = "raw_contact_id = ?"; String[] selectionArgs = {String.valueOf(id)}; Cursor c = getContentResolver().query(dataUri, new String[]{"data1", "mimetype"}, selection, selectionArgs, null); if(c != null && c.getCount() > 0) { while(c.moveToNext()) { String mimetype = c.getString(1); // 当前取的是mimetype的值 String data1 = c.getString(0); // 当前取的是data1数据 if("vnd.android.cursor.item/phone_v2".equals(mimetype)) { Log.i(TAG, "号码: " + data1); } else if("vnd.android.cursor.item/name".equals(mimetype)) { Log.i(TAG, "姓名: " + data1); } else if("vnd.android.cursor.item/email_v2".equals(mimetype)) { Log.i(TAG, "邮箱: " + data1); } } c.close(); } } cursor.close(); } } public void addContacts(View v) { Uri uri = Uri.parse("content://com.android.contacts/raw_contacts"); Uri dataUri = Uri.parse("content://com.android.contacts/data"); // 1. 在raw_contacts表中添加一个记录 // 取raw_contacts表中contact_id的值 Cursor cursor = getContentResolver().query(uri, new String[]{"contact_id"}, null, null, "contact_id desc limit 1"); if(cursor != null && cursor.moveToFirst()) { int contact_id = cursor.getInt(0); contact_id ++; cursor.close(); ContentValues values = new ContentValues(); values.put("contact_id", contact_id); getContentResolver().insert(uri, values); // 2. 根据上面添加记录的id, 取data表中添加三条数据 // 存号码 values = new ContentValues(); values.put("mimetype", "vnd.android.cursor.item/phone_v2"); values.put("data1", "10086"); values.put("raw_contact_id", contact_id); getContentResolver().insert(dataUri, values); // 存姓名 values = new ContentValues(); values.put("mimetype", "vnd.android.cursor.item/name"); values.put("data1", "中国移动"); values.put("raw_contact_id", contact_id); getContentResolver().insert(dataUri, values); // 存邮箱 values = new ContentValues(); values.put("mimetype", "vnd.android.cursor.item/email_v2"); values.put("data1", "10086@kengni.com"); values.put("raw_contact_id", contact_id); getContentResolver().insert(dataUri, values); } } } 内容观察者使用内容观察者: 发件箱的uri:content://sms/outbox package com.itheima28.contentobserverdemo; import android.app.Activity; import android.content.ContentResolver; import android.database.ContentObserver; import android.database.Cursor; import android.net.Uri; import android.os.Bundle; import android.os.Handler; import android.util.Log; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // 监听系统短信 ContentResolver resolver = getContentResolver(); // 注册一个内容观察者观察短信数据库 resolver.registerContentObserver(Uri.parse("content://sms/"), true, new MyContentObserver(new Handler())); } /** * @author andong * 内容观察者 */ class MyContentObserver extends ContentObserver { private static final String TAG = "MyContentObserver"; public MyContentObserver(Handler handler) { super(handler); } /** * 当被监听的内容发生改变时回调 */ @Override public void onChange(boolean selfChange) { Log.i(TAG, "短信改变了"); Uri uri = Uri.parse("content://sms/outbox"); // 发件箱的uri // 查询发件箱的内容 Cursor cursor = getContentResolver().query(uri, new String[]{"address", "date", "body"}, null, null, null); if(cursor != null && cursor.getCount() > 0) { String address; long date; String body; while(cursor.moveToNext()) { address = cursor.getString(0); date = cursor.getLong(1); body = cursor.getString(2); Log.i(TAG, "号码: " + address + ", 日期: " + date + ", 内容: " + body); } cursor.close(); } } } } 网络图片查看器 Android notResponding(应用程序无响应) 阻塞了主线程 ANR异常异常: CalledFromWrongThreadException: Only theoriginal thread that created a view hierarchy can touch its views. 只有原始的线程(主线程, ui线程)才能修改view对象. 在子线程中修改view的显示状态, 会报上面异常. 子线程网络图片查看器和Handler消息处理器 <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.itheima28.netphoto" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" />  <uses-permission android:name="android.permission.INTERNET"/> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.itheima28.netphoto.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context=".MainActivity" > <ImageView android:id="@+id/iv_icon" android:layout_width="fill_parent" android:layout_height="0dip" android:layout_weight="1" /> <LinearLayout android:layout_width="fill_parent" android:layout_height="wrap_content" android:orientation="horizontal" > <EditText android:id="@+id/et_url" android:layout_width="0dip" android:text="http://imgstatic.baidu.com/img/image/d833c895d143ad4bf450b6dd80025aafa40f06b4_%E5%89%AF%E6%9C%AC.jpg" android:layout_height="wrap_content" android:singleLine="true" android:layout_weight="1" /> <Button android:id="@+id/btn_submit" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Go" android:textSize="20sp" /> </LinearLayout> </LinearLayout> package com.itheima28.netphoto; import java.io.InputStream; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import javax.net.ssl.HttpsURLConnection; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.app.Activity; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.util.Log; import android.view.Menu; import android.view.View; import android.view.View.OnClickListener; import android.widget.EditText; import android.widget.ImageView; import android.widget.Toast; public class MainActivity extends Activity implements OnClickListener { private static final String TAG = "MainActivity"; protected static final int ERROR = 1; private EditText etUrl; private ImageView ivIcon; private final int SUCCESS = 0; private Handler handler = new Handler() { /** * 接收消息 */ @Override public void handleMessage(Message msg) { super.handleMessage(msg); Log.i(TAG, "what = " + msg.what); if(msg.what == SUCCESS) { // 当前是访问网络, 去显示图片 ivIcon.setImageBitmap((Bitmap) msg.obj); // 设置imageView显示的图片 } else if(msg.what == ERROR) { Toast.makeText(MainActivity.this, "抓去失败", 0).show(); } } }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); ivIcon = (ImageView) findViewById(R.id.iv_icon); etUrl = (EditText) findViewById(R.id.et_url); findViewById(R.id.btn_submit).setOnClickListener(this); } @Override public void onClick(View v) { final String url = etUrl.getText().toString(); new Thread(new Runnable() { @Override public void run() { Bitmap bitmap = getImageFromNet(url); // ivIcon.setImageBitmap(bitmap); // 设置imageView显示的图片 if(bitmap != null) { Message msg = new Message(); msg.what = SUCCESS; msg.obj = bitmap; handler.sendMessage(msg); } else { Message msg = new Message(); msg.what = ERROR; handler.sendMessage(msg); } }}).start(); } /** * 根据url连接取网络抓去图片返回 * @param url * @return url对应的图片 */ private Bitmap getImageFromNet(String url) { HttpURLConnection conn = null; try { URL mURL = new URL(url); // 创建一个url对象 // 得到http的连接对象 conn = (HttpURLConnection) mURL.openConnection(); conn.setRequestMethod("GET"); // 设置请求方法为Get conn.setConnectTimeout(10000); // 设置连接服务器的超时时间, 如果超过10秒钟, 没有连接成功, 会抛异常 conn.setReadTimeout(5000); // 设置读取数据时超时时间, 如果超过5秒, 抛异常 conn.connect(); // 开始链接 int responseCode = conn.getResponseCode(); // 得到服务器的响应码 if(responseCode == 200) { // 访问成功 InputStream is = conn.getInputStream(); // 获得服务器返回的流数据 Bitmap bitmap = BitmapFactory.decodeStream(is); // 根据流数据创建一个bitmap位图对象 return bitmap; } else { Log.i(TAG, "访问失败: responseCode = " + responseCode); } } catch (Exception e) { e.printStackTrace(); } finally { if(conn != null) { conn.disconnect(); // 断开连接 } } return null; } } html查看器 <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.itheima28.htmldemo" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" /> <uses-permission android:name="android.permission.INTERNET"/> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.itheima28.htmldemo.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context=".MainActivity" > <LinearLayout android:layout_width="fill_parent" android:layout_height="wrap_content" android:orientation="horizontal" > <EditText android:id="@+id/et_url" android:layout_width="0dip" android:text="http://www.baidu.com" android:layout_height="wrap_content" android:singleLine="true" android:layout_weight="1" /> <Button android:layout_width="wrap_content" android:layout_height="wrap_content" android:onClick="getHtml" android:text="GO" /> </LinearLayout> <ScrollView android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:id="@+id/tv_html" android:layout_width="fill_parent" android:layout_height="fill_parent" /> </ScrollView> </LinearLayout> package com.itheima28.htmldemo; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.net.HttpURLConnection; import java.net.URL; import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.text.TextUtils; import android.util.Log; import android.view.View; import android.widget.EditText; import android.widget.TextView; import android.widget.Toast; public class MainActivity extends Activity { private static final String TAG = "MainActivity"; private static final int SUCCESS = 0; protected static final int ERROR = 1; private EditText etUrl; private TextView tvHtml; private Handler handler = new Handler() { @Override public void handleMessage(Message msg) { super.handleMessage(msg); switch (msg.what) { case SUCCESS: tvHtml.setText((String) msg.obj); break; case ERROR: Toast.makeText(MainActivity.this, "访问失败", 0).show(); break; default: break; } } }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); etUrl = (EditText) findViewById(R.id.et_url); tvHtml = (TextView) findViewById(R.id.tv_html); } public void getHtml(View v) { final String url = etUrl.getText().toString(); new Thread(new Runnable() { @Override public void run() { // 请求网络 String html = getHtmlFromInternet(url); if(!TextUtils.isEmpty(html)) { // 更新textview的显示了 Message msg = new Message(); msg.what = SUCCESS; msg.obj = html; handler.sendMessage(msg); } else { Message msg = new Message(); msg.what = ERROR; handler.sendMessage(msg); } } }).start(); } /** * 根据给定的url访问网络, 抓去html代码 * @param url * @return */ protected String getHtmlFromInternet(String url) { try { URL mURL = new URL(url); HttpURLConnection conn = (HttpURLConnection) mURL.openConnection(); conn.setRequestMethod("GET"); conn.setConnectTimeout(10000); conn.setReadTimeout(5000); // conn.connect(); int responseCode = conn.getResponseCode(); if(responseCode == 200) { InputStream is = conn.getInputStream(); String html = getStringFromInputStream(is); return html; } else { Log.i(TAG, "访问失败: " + responseCode); } } catch (Exception e) { e.printStackTrace(); } return null; } /** * 根据流返回一个字符串信息 * @param is * @return * @throws IOException */ private String getStringFromInputStream(InputStream is) throws IOException { ByteArrayOutputStream baos = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len = -1; while((len = is.read(buffer)) != -1) { baos.write(buffer, 0, len); } is.close(); String html = baos.toString(); // 把流中的数据转换成字符串, 采用的编码是: utf-8 String charset = "utf-8"; if(html.contains("gbk") || html.contains("gb2312") || html.contains("GBK") || html.contains("GB2312")) { // 如果包含gbk, gb2312编码, 就采用gbk编码进行对字符串编码 charset = "gbk"; } html = new String(baos.toByteArray(), charset); // 对原有的字节数组进行使用处理后的编码名称进行编码 baos.close(); return html; } } html查看器乱码问题 /** * 根据流返回一个字符串信息 * @param is * @return * @throws IOException */ private String getStringFromInputStream(InputStream is) throws IOException { ByteArrayOutputStream baos = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len = -1; while((len = is.read(buffer)) != -1) { baos.write(buffer, 0, len); } is.close(); String html = baos.toString(); // 把流中的数据转换成字符串, 采用的编码是: utf-8 String charset = "utf-8"; if(html.contains("gbk") || html.contains("gb2312") || html.contains("GBK") || html.contains("GB2312")) { // 如果包含gbk, gb2312编码, 就采用gbk编码进行对字符串编码 charset = "gbk"; } html = new String(baos.toByteArray(), charset); // 对原有的字节数组进行使用处理后的编码名称进行编码 baos.close(); return html; } 使用HttpURLConnection采用Post方式请求数据 Servlet服务器程序 package com.itheima28.servlet; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class LoginServlet extends HttpServlet { /** * The doGet method of the servlet. <br> * * This method is called when a form has its tag value method equals to get. * * @param request the request send by the client to the server * @param response the response send by the server to the client * @throws ServletException if an error occurred * @throws IOException if an error occurred */ public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String username = request.getParameter("username"); // 采用的编码是: iso-8859-1 String password = request.getParameter("password"); // 采用iso8859-1的编码对姓名进行逆转, 转换成字节数组, 再使用utf-8编码对数据进行转换, 字符串 username = new String(username.getBytes("iso8859-1"), "utf-8"); password = new String(password.getBytes("iso8859-1"), "utf-8"); System.out.println("姓名: " + username); System.out.println("密码: " + password); if("lisi".equals(username) && "123".equals(password)) { /* * getBytes 默认情况下, 使用的iso8859-1的编码, 但如果发现码表中没有当前字符, * 会使用当前系统下的默认编码: GBK */ response.getOutputStream().write("登录成功".getBytes("utf-8")); } else { response.getOutputStream().write("登录失败".getBytes("utf-8")); } } /** * The doPost method of the servlet. <br> * * This method is called when a form has its tag value method equals to post. * * @param request the request send by the client to the server * @param response the response send by the server to the client * @throws ServletException if an error occurred * @throws IOException if an error occurred */ public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("doPost"); doGet(request, response); } } Android客户端 <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.itheim28.submitdata" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" /> <uses-permission android:name="android.permission.INTERNET"/> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.itheim28.submitdata.MainActivity2" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context=".MainActivity" > <EditText android:id="@+id/et_username" android:layout_width="fill_parent" android:layout_height="wrap_content" android:hint="请输入姓名" /> <EditText android:id="@+id/et_password" android:layout_width="fill_parent" android:layout_height="wrap_content" android:hint="请输入密码" /> <Button android:layout_width="wrap_content" android:layout_height="wrap_content" android:onClick="doGet" android:text="Get方式提交" /> <Button android:layout_width="wrap_content" android:layout_height="wrap_content" android:onClick="doPost" android:text="Post方式提交" /> </LinearLayout> package com.itheim28.submitdata.utils; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import java.net.URLConnection; import java.net.URLEncoder; import android.util.Log; public class NetUtils { private static final String TAG = "NetUtils"; /** * 使用post的方式登录 * @param userName * @param password * @return */ public static String loginOfPost(String userName, String password) { HttpURLConnection conn = null; try { URL url = new URL("http://10.0.2.2:8080/ServerItheima28/servlet/LoginServlet"); conn = (HttpURLConnection) url.openConnection(); conn.setRequestMethod("POST"); conn.setConnectTimeout(10000); // 连接的超时时间 conn.setReadTimeout(5000); // 读数据的超时时间 conn.setDoOutput(true); // 必须设置此方法, 允许输出 // conn.setRequestProperty("Content-Length", 234); // 设置请求头消息, 可以设置多个 // post请求的参数 String data = "username=" + userName + "&password=" + password; // 获得一个输出流, 用于向服务器写数据, 默认情况下, 系统不允许向服务器输出内容 OutputStream out = conn.getOutputStream(); out.write(data.getBytes()); out.flush(); out.close(); int responseCode = conn.getResponseCode(); if(responseCode == 200) { InputStream is = conn.getInputStream(); String state = getStringFromInputStream(is); return state; } else { Log.i(TAG, "访问失败: " + responseCode); } } catch (Exception e) { e.printStackTrace(); } finally { if(conn != null) { conn.disconnect(); } } return null; } /** * 使用get的方式登录 * @param userName * @param password * @return 登录的状态 */ public static String loginOfGet(String userName, String password) { HttpURLConnection conn = null; try { String data = "username=" + URLEncoder.encode(userName) + "&password=" + URLEncoder.encode(password); URL url = new URL("http://10.0.2.2:8080/ServerItheima28/servlet/LoginServlet?" + data); conn = (HttpURLConnection) url.openConnection(); conn.setRequestMethod("GET"); // get或者post必须得全大写 conn.setConnectTimeout(10000); // 连接的超时时间 conn.setReadTimeout(5000); // 读数据的超时时间 int responseCode = conn.getResponseCode(); if(responseCode == 200) { InputStream is = conn.getInputStream(); String state = getStringFromInputStream(is); return state; } else { Log.i(TAG, "访问失败: " + responseCode); } } catch (Exception e) { e.printStackTrace(); } finally { if(conn != null) { conn.disconnect(); // 关闭连接 } } return null; } /** * 根据流返回一个字符串信息 * @param is * @return * @throws IOException */ private static String getStringFromInputStream(InputStream is) throws IOException { ByteArrayOutputStream baos = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len = -1; while((len = is.read(buffer)) != -1) { baos.write(buffer, 0, len); } is.close(); String html = baos.toString(); // 把流中的数据转换成字符串, 采用的编码是: utf-8 // String html = new String(baos.toByteArray(), "GBK"); baos.close(); return html; } } package com.itheim28.submitdata; import com.itheim28.submitdata.utils.NetUtils; import android.os.Bundle; import android.app.Activity; import android.view.Menu; import android.view.View; import android.widget.EditText; import android.widget.Toast; public class MainActivity extends Activity { private EditText etUserName; private EditText etPassword; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); etUserName = (EditText) findViewById(R.id.et_username); etPassword = (EditText) findViewById(R.id.et_password); } public void doGet(View v) { final String userName = etUserName.getText().toString(); final String password = etPassword.getText().toString(); new Thread( new Runnable() { @Override public void run() { // 使用get方式抓去数据 final String state = NetUtils.loginOfGet(userName, password); // 执行任务在主线程中 runOnUiThread(new Runnable() { @Override public void run() { // 就是在主线程中操作 Toast.makeText(MainActivity.this, state, 0).show(); } }); } }).start(); } public void doPost(View v) { final String userName = etUserName.getText().toString(); final String password = etPassword.getText().toString(); new Thread(new Runnable() { @Override public void run() { final String state = NetUtils.loginOfPost(userName, password); // 执行任务在主线程中 runOnUiThread(new Runnable() { @Override public void run() { // 就是在主线程中操作 Toast.makeText(MainActivity.this, state, 0).show(); } }); } }).start(); } } 开源项目简介 github.com 开源网站, 一个大的仓库. 存放的都是框架 android-async-http-master.zip android-smart-image-view-master.zip 直接拿来用最火的android开源项目 csdn的帖子

【黑马Android】(04)数据库的创建和sql语句增删改查/LinearLayout展示列表数据/ListView的使用和BaseAdater/内容提供者创建

数据库的创建和sql语句增删改查 1. 加载驱动. 2. 连接数据库. 3. 操作数据库. 创建表: create table person( _id integer primary key, name varchar(20), age integer ); 添加: insert into person(name, age) values('lisi', 19); 删除: delete from person where _id = 1; 修改: update person set name = '李四' where name = '王五'; 查询所有: select * from person; 查询单条: select * from person where name = 'zhangsan'; SQLiteExpert3, pc上的工具软件。 package com.itheima28.sqlitedemo.dao; import java.util.ArrayList; import java.util.List; import android.content.Context; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper; import com.itheima28.sqlitedemo.entities.Person; public class PersonDao { private PersonSQLiteOpenHelper mOpenHelper; // 数据库的帮助类对象 public PersonDao(Context context) { mOpenHelper = new PersonSQLiteOpenHelper(context); } /** * 添加到person表一条数据 * @param person */ public void insert(Person person) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); if(db.isOpen()) { // 如果数据库打开, 执行添加的操作 // 执行添加到数据库的操作 db.execSQL("insert into person(name, age) values(?, ?);", new Object[]{person.getName(), person.getAge()}); db.close(); // 数据库关闭 } } /** * 更据id删除记录 * @param id */ public void delete(int id) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); // 获得可写的数据库对象 if(db.isOpen()) { // 如果数据库打开, 执行添加的操作 db.execSQL("delete from person where _id = ?;", new Integer[]{id}); db.close(); // 数据库关闭 } } /** * 根据id找到记录, 并且修改姓名 * @param id * @param name */ public void update(int id, String name) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); if(db.isOpen()) { // 如果数据库打开, 执行添加的操作 db.execSQL("update person set name = ? where _id = ?;", new Object[]{name, id}); db.close(); // 数据库关闭 } } public List<Person> queryAll() { SQLiteDatabase db = mOpenHelper.getReadableDatabase(); // 获得一个只读的数据库对象 if(db.isOpen()) { Cursor cursor = db.rawQuery("select _id, name, age from person;", null); if(cursor != null && cursor.getCount() > 0) { List<Person> personList = new ArrayList<Person>(); int id; String name; int age; while(cursor.moveToNext()) { id = cursor.getInt(0); // 取第0列的数据 id name = cursor.getString(1); // 取姓名 age = cursor.getInt(2); // 取年龄 personList.add(new Person(id, name, age)); } db.close(); return personList; } db.close(); } return null; } /** * 根据id查询人 * @param id * @return */ public Person queryItem(int id) { SQLiteDatabase db = mOpenHelper.getReadableDatabase(); // 获得一个只读的数据库对象 if(db.isOpen()) { Cursor cursor = db.rawQuery("select _id, name, age from person where _id = ?;", new String[]{id + ""}); if(cursor != null && cursor.moveToFirst()) { int _id = cursor.getInt(0); String name = cursor.getString(1); int age = cursor.getInt(2); db.close(); return new Person(_id, name, age); } db.close(); } return null; } } package com.itheima28.sqlitedemo.db; import android.content.Context; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteDatabase.CursorFactory; import android.database.sqlite.SQLiteOpenHelper; import android.util.Log; /** * @author andong * 数据库帮助类, 用于创建和管理数据库的. */ public class PersonSQLiteOpenHelper extends SQLiteOpenHelper { private static final String TAG = "PersonSQLiteOpenHelper"; /** * 数据库的构造函数 * @param context * * name 数据库名称 * factory 游标工程 * version 数据库的版本号不可以小于1 */ public PersonSQLiteOpenHelper(Context context) { super(context, "itheima28.db", null, 2); } /** * 数据库第一次创建时回调此方法. * 初始化一些表 */ @Override public void onCreate(SQLiteDatabase db) { // 操作数据库 String sql = "create table person(_id integer primary key, name varchar(20), age integer);"; db.execSQL(sql); // 创建person表 } /** * 数据库的版本号更新时回调此方法, * 更新数据库的内容(删除表, 添加表, 修改表) */ @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { if(oldVersion == 1 && newVersion == 2) { Log.i(TAG, "数据库更新啦"); // 在person表中添加一个余额列balance db.execSQL("alter table person add balance integer;"); } } } package com.itheima28.sqlitedemo.entities; public class Person { private int id; private String name; private int age; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public Person() { super(); // TODO Auto-generated constructor stub } public Person(int id, String name, int age) { super(); this.id = id; this.name = name; this.age = age; } @Override public String toString() { return "Person [id=" + id + ", name=" + name + ", age=" + age + "]"; } } package com.itheima28.sqlitedemo.test; import java.util.List; import com.itheima28.sqlitedemo.dao.PersonDao; import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper; import com.itheima28.sqlitedemo.entities.Person; import android.database.SQLException; import android.database.sqlite.SQLiteDatabase; import android.test.AndroidTestCase; import android.util.Log; public class TestCase extends AndroidTestCase { private static final String TAG = "TestCase"; public void test() { // 数据库什么时候创建 PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext()); // 第一次连接数据库时创建数据库文件. onCreate会被调用 openHelper.getReadableDatabase(); } public void testInsert() { PersonDao dao = new PersonDao(getContext()); dao.insert(new Person(0, "冠希", 28)); } public void testDelete() { PersonDao dao = new PersonDao(getContext()); dao.delete(1); } public void testUpdate() { PersonDao dao = new PersonDao(getContext()); dao.update(3, "凤姐"); } public void testQueryAll() { PersonDao dao = new PersonDao(getContext()); List<Person> personList = dao.queryAll(); for (Person person : personList) { Log.i(TAG, person.toString()); } } public void testQueryItem() { PersonDao dao = new PersonDao(getContext()); Person person = dao.queryItem(4); Log.i(TAG, person.toString()); } public void testTransaction() { PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext()); SQLiteDatabase db = openHelper.getWritableDatabase(); if(db.isOpen()) { try { // 开启事务 db.beginTransaction(); // 1. 从张三账户中扣1000块钱 db.execSQL("update person set balance = balance - 1000 where name = 'zhangsan';"); // ATM机, 挂掉了. // int result = 10 / 0; // 2. 向李四账户中加1000块钱 db.execSQL("update person set balance = balance + 1000 where name = 'lisi';"); // 标记事务成功 db.setTransactionSuccessful(); } finally { // 停止事务 db.endTransaction(); } db.close(); } } public void testTransactionInsert() { PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext()); SQLiteDatabase db = openHelper.getWritableDatabase(); if(db.isOpen()) { // 1. 记住当前的时间 long start = System.currentTimeMillis(); // 2. 开始添加数据 try { db.beginTransaction(); for (int i = 0; i < 10000; i++) { db.execSQL("insert into person(name, age, balance) values('wang" + i + "', " + (10 + i) + ", " + (10000 + i) + ")"); } db.setTransactionSuccessful(); } finally { db.endTransaction(); } // 3. 记住结束时间, 计算耗时时间 long end = System.currentTimeMillis(); long diff = end - start; Log.i(TAG, "耗时: " + diff + "毫秒"); db.close(); } } } <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.itheima28.sqlitedemo" android:versionCode="1" android:versionName="1.0" > <instrumentation android:name="android.test.InstrumentationTestRunner" android:targetPackage="com.itheima28.sqlitedemo" > </instrumentation> <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" /> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <uses-library android:name="android.test.runner" /> <activity android:name="com.itheima28.sqlitedemo.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> 使用api方式查询数据库和sqlite3工具 adb shell package com.itheima28.sqlitedemo.dao; import java.util.ArrayList; import java.util.List; import android.content.ContentValues; import android.content.Context; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.util.Log; import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper; import com.itheima28.sqlitedemo.entities.Person; public class PersonDao2 { private static final String TAG = "PersonDao2"; private PersonSQLiteOpenHelper mOpenHelper; // 数据库的帮助类对象 public PersonDao2(Context context) { mOpenHelper = new PersonSQLiteOpenHelper(context); } /** * 添加到person表一条数据 * @param person */ public void insert(Person person) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); if(db.isOpen()) { // 如果数据库打开, 执行添加的操作 ContentValues values = new ContentValues(); values.put("name", person.getName()); // key作为要存储的列名, value对象列的值 values.put("age", person.getAge()); long id = db.insert("person", "name", values); Log.i(TAG, "id: " + id); db.close(); // 数据库关闭 } } /** * 更据id删除记录 * @param id */ public void delete(int id) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); // 获得可写的数据库对象 if(db.isOpen()) { // 如果数据库打开, 执行添加的操作 String whereClause = "_id = ?"; String[] whereArgs = {id + ""}; int count = db.delete("person", whereClause, whereArgs); Log.i(TAG, "删除了: " + count + "行"); db.close(); // 数据库关闭 } } /** * 根据id找到记录, 并且修改姓名 * @param id * @param name */ public void update(int id, String name) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); if(db.isOpen()) { // 如果数据库打开, 执行添加的操作 ContentValues values = new ContentValues(); values.put("name", name); int count = db.update("person", values, "_id = ?", new String[]{id + ""}); Log.i(TAG, "修改了: " + count + "行"); db.close(); // 数据库关闭 } } public List<Person> queryAll() { SQLiteDatabase db = mOpenHelper.getReadableDatabase(); // 获得一个只读的数据库对象 if(db.isOpen()) { String[] columns = {"_id", "name", "age"}; // 需要的列 String selection = null; // 选择条件, 给null查询所有 String[] selectionArgs = null; // 选择条件的参数, 会把选择条件中的? 替换成数据中的值 String groupBy = null; // 分组语句 group by name String having = null; // 过滤语句 String orderBy = null; // 排序 Cursor cursor = db.query("person", columns, selection, selectionArgs, groupBy, having, orderBy); int id; String name; int age; if(cursor != null && cursor.getCount() > 0) { List<Person> personList = new ArrayList<Person>(); while(cursor.moveToNext()) { // 向下移一位, 知道最后一位, 不可以往下移动了, 停止. id = cursor.getInt(0); name = cursor.getString(1); age = cursor.getInt(2); personList.add(new Person(id, name, age)); } db.close(); return personList; } db.close(); } return null; } /** * 根据id查询人 * @param id * @return */ public Person queryItem(int id) { SQLiteDatabase db = mOpenHelper.getReadableDatabase(); // 获得一个只读的数据库对象 if(db.isOpen()) { String[] columns = {"_id", "name", "age"}; // 需要的列 String selection = "_id = ?"; // 选择条件, 给null查询所有 String[] selectionArgs = {id + ""}; // 选择条件的参数, 会把选择条件中的? 替换成数据中的值 String groupBy = null; // 分组语句 group by name String having = null; // 过滤语句 String orderBy = null; // 排序 Cursor cursor = db.query("person", columns, selection, selectionArgs, groupBy, having, orderBy); if(cursor != null && cursor.moveToFirst()) { // cursor对象不为null, 并且可以移动到第一行 int _id = cursor.getInt(0); String name = cursor.getString(1); int age = cursor.getInt(2); db.close(); return new Person(_id, name, age); } db.close(); } return null; } } package com.itheima28.sqlitedemo.test; import java.util.List; import android.test.AndroidTestCase; import android.util.Log; import com.itheima28.sqlitedemo.dao.PersonDao2; import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper; import com.itheima28.sqlitedemo.entities.Person; public class TestCase2 extends AndroidTestCase { private static final String TAG = "TestCase"; public void test() { // 数据库什么时候创建 PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext()); // 第一次连接数据库时创建数据库文件. onCreate会被调用 openHelper.getReadableDatabase(); } public void testInsert() { PersonDao2 dao = new PersonDao2(getContext()); dao.insert(new Person(0, "zhouqi", 88)); } public void testDelete() { PersonDao2 dao = new PersonDao2(getContext()); dao.delete(8); } public void testUpdate() { PersonDao2 dao = new PersonDao2(getContext()); dao.update(3, "fengjie"); } public void testQueryAll() { PersonDao2 dao = new PersonDao2(getContext()); List<Person> personList = dao.queryAll(); for (Person person : personList) { Log.i(TAG, person.toString()); } } public void testQueryItem() { PersonDao2 dao = new PersonDao2(getContext()); Person person = dao.queryItem(4); Log.i(TAG, person.toString()); } } 事务的操作事务: update person set balance = balance - 100 where name = 'lisi'; update person set balance = balance + 100 where name = 'zhangsan'; // 开启事务 db.beginTransaction(); // 标记事务成功 db.setTransactionSuccessful(); // 停止事务 db.endTransaction(); public void testTransaction() { PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext()); SQLiteDatabase db = openHelper.getWritableDatabase(); if(db.isOpen()) { try { // 开启事务 db.beginTransaction(); // 1. 从张三账户中扣1000块钱 db.execSQL("update person set balance = balance - 1000 where name = 'zhangsan';"); // ATM机, 挂掉了. // int result = 10 / 0; // 2. 向李四账户中加1000块钱 db.execSQL("update person set balance = balance + 1000 where name = 'lisi';"); // 标记事务成功 db.setTransactionSuccessful(); } finally { // 停止事务 db.endTransaction(); } db.close(); } } public void testTransactionInsert() { PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext()); SQLiteDatabase db = openHelper.getWritableDatabase(); if(db.isOpen()) { // 1. 记住当前的时间 long start = System.currentTimeMillis(); // 2. 开始添加数据 try { db.beginTransaction(); for (int i = 0; i < 10000; i++) { db.execSQL("insert into person(name, age, balance) values('wang" + i + "', " + (10 + i) + ", " + (10000 + i) + ")"); } db.setTransactionSuccessful(); } finally { db.endTransaction(); } // 3. 记住结束时间, 计算耗时时间 long end = System.currentTimeMillis(); long diff = end - start; Log.i(TAG, "耗时: " + diff + "毫秒"); db.close(); } } LinearLayout展示列表数据 <ScrollView xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" > <LinearLayout android:id="@+id/ll_list" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > </LinearLayout> </ScrollView> package com.itheima28.sqlitedemo; import java.util.List; import com.itheima28.sqlitedemo.dao.PersonDao; import com.itheima28.sqlitedemo.entities.Person; import android.os.Bundle; import android.app.Activity; import android.view.Menu; import android.view.View; import android.widget.LinearLayout; import android.widget.TextView; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); LinearLayout llList = (LinearLayout) findViewById(R.id.ll_list); PersonDao dao = new PersonDao(this); List<Person> personList = dao.queryAll(); if(personList != null) { TextView tv; for (Person person : personList) { // 向线性布局中添加一个textview tv = new TextView(this); tv.setText(person.toString()); tv.setTextSize(18); llList.addView(tv); } } } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } } ListView的使用和BaseAdater <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <ListView android:id="@+id/listview" android:layout_width="match_parent" android:layout_height="match_parent" > </ListView> </LinearLayout> package com.itheima28.sqlitedemo; import java.util.List; import com.itheima28.sqlitedemo.dao.PersonDao; import com.itheima28.sqlitedemo.entities.Person; import android.os.Bundle; import android.app.Activity; import android.util.Log; import android.view.Menu; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.LinearLayout; import android.widget.ListView; import android.widget.TextView; public class MainActivity extends Activity { private List<Person> personList; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); ListView mListView = (ListView) findViewById(R.id.listview); PersonDao dao = new PersonDao(this); personList = dao.queryAll(); // 把view层对象ListView和控制器BaseAdapter关联起来 mListView.setAdapter(new MyAdapter()); } /** * @author andong * 数据适配器 */ class MyAdapter extends BaseAdapter { private static final String TAG = "MyAdapter"; /** * 定义ListView的数据的长度 */ @Override public int getCount() { return personList.size(); } @Override public Object getItem(int position) { // TODO Auto-generated method stub return null; } @Override public long getItemId(int position) { // TODO Auto-generated method stub return 0; } /** * 此方法返回的是ListView的列表中某一行的View对象 * position 当前返回的view的索引位置 * convertView 缓存对象 * parent 就是ListView对象 */ @Override public View getView(int position, View convertView, ViewGroup parent) { TextView tv = null; if(convertView != null) { // 判断缓存对象是否为null, 不为null时已经缓存了对象 Log.i(TAG, "getView: 复用缓存" + position); tv = (TextView) convertView; } else { // 等于null, 说明第一次显示, 新创建 Log.i(TAG, "getView: 新建" + position); tv = new TextView(MainActivity.this); } tv.setTextSize(25); Person person = personList.get(position); // 获得指定位置的数据, 进行对TextView的绑定 tv.setText(person.toString()); return tv; } } } package com.itheima28.sqlitedemo; import java.util.List; import com.itheima28.sqlitedemo.dao.PersonDao; import com.itheima28.sqlitedemo.entities.Person; import android.os.Bundle; import android.app.Activity; import android.util.Log; import android.view.LayoutInflater; import android.view.Menu; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.LinearLayout; import android.widget.ListView; import android.widget.TextView; public class MainActivity2 extends Activity { private List<Person> personList; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); ListView mListView = (ListView) findViewById(R.id.listview); PersonDao dao = new PersonDao(this); personList = dao.queryAll(); // 把view层对象ListView和控制器BaseAdapter关联起来 mListView.setAdapter(new MyAdapter()); } /** * @author andong * 数据适配器 */ class MyAdapter extends BaseAdapter { private static final String TAG = "MyAdapter"; /** * 定义ListView的数据的长度 */ @Override public int getCount() { return personList.size(); } @Override public Object getItem(int position) { // TODO Auto-generated method stub return null; } @Override public long getItemId(int position) { // TODO Auto-generated method stub return 0; } /** * 此方法返回的是ListView的列表中某一行的View对象 * position 当前返回的view的索引位置 * convertView 缓存对象 * parent 就是ListView对象 */ @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; if(convertView == null) { // 布局填充器对象, 用于把xml布局转换成view对象 LayoutInflater inflater = MainActivity2.this.getLayoutInflater(); view = inflater.inflate(R.layout.listview_item, null); } else { view = convertView; } // 给view中的姓名和年龄赋值 TextView tvName = (TextView) view.findViewById(R.id.tv_listview_item_name); TextView tvAge = (TextView) view.findViewById(R.id.tv_listview_item_age); Person person = personList.get(position); tvName.setText("姓名: " + person.getName()); tvAge.setText("年龄: " + person.getAge()); return view; } } } listview_item.xml <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal" android:padding="10dip" > <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/f078" /> <LinearLayout android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginLeft="10dip" android:orientation="vertical" > <TextView android:id="@+id/tv_listview_item_name" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="张三" /> <TextView android:id="@+id/tv_listview_item_age" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="5dip" android:textColor="#FF0000" android:text="35" /> </LinearLayout> </LinearLayout> 其他两种绑定ListView数据的方式 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MainActivity" > <ListView android:id="@+id/listview" android:layout_width="match_parent" android:layout_height="match_parent" /> </RelativeLayout> listview_item.xml <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center_vertical" android:orientation="horizontal" android:padding="10dip" > <ImageView android:id="@+id/iv_icon" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/f007" /> <TextView android:id="@+id/tv_name" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="10dip" android:text="张三" android:textColor="#FF0000" android:textSize="23sp" /> </LinearLayout> package com.itheima28.simpleadapterdemo; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import android.app.Activity; import android.os.Bundle; import android.view.Menu; import android.widget.ArrayAdapter; import android.widget.ListView; import android.widget.SimpleAdapter; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); ListView mListView = (ListView) findViewById(R.id.listview); List<Map<String, Object>> data = new ArrayList<Map<String,Object>>(); Map<String, Object> map = new HashMap<String, Object>(); map.put("name", "张三1"); map.put("icon", R.drawable.f007); data.add(map); map = new HashMap<String, Object>(); map.put("name", "张三2"); map.put("icon", R.drawable.f007); data.add(map); map = new HashMap<String, Object>(); map.put("name", "张三3"); map.put("icon", R.drawable.f007); data.add(map); map = new HashMap<String, Object>(); map.put("name", "张三4"); map.put("icon", R.drawable.f007); data.add(map); map = new HashMap<String, Object>(); map.put("name", "张三5"); map.put("icon", R.drawable.f007); data.add(map); SimpleAdapter adapter = new SimpleAdapter( this, // 上下文 data, // listView绑定的数据 R.layout.listview_item, // listview的子条目的布局的id new String[]{"name", "icon"}, // data数据中的map集合里的key new int[]{R.id.tv_name, R.id.iv_icon}); // resource 中的id mListView.setAdapter(adapter); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } } 内容提供者创建 <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.itheima28.sqlitedemo" android:versionCode="1" android:versionName="1.0" > <instrumentation android:name="android.test.InstrumentationTestRunner" android:targetPackage="com.itheima28.sqlitedemo" > </instrumentation> <permission android:name="aa.bb.cc.read" ></permission> <permission android:name="aa.bb.cc.write" ></permission> <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" /> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <uses-library android:name="android.test.runner" /> <activity android:name="com.itheima28.sqlitedemo.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <provider android:name=".providers.PersonContentProvider" android:authorities="com.itheima28.sqlitedemo.providers.PersonContentProvider" android:readPermission="aa.bb.cc.read" android:writePermission="aa.bb.cc.write" > </provider> </application> </manifest> package com.itheima28.sqlitedemo.providers; import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper; import android.content.ContentProvider; import android.content.ContentUris; import android.content.ContentValues; import android.content.UriMatcher; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.net.Uri; public class PersonContentProvider extends ContentProvider { private static final String AUTHORITY = "com.itheima28.sqlitedemo.providers.PersonContentProvider"; private static final int PRESON_INSERT_CODE = 0; // 操作person表添加的操作的uri匹配码 private static final int PERSON_DELETE_CODE = 1; private static final int PERSON_UPDATE_CODE = 2; private static final int PERSON_QUERY_ALL_CODE = 3; private static final int PERSON_QUERY_ITEM_CODE = 4; private static UriMatcher uriMatcher; private PersonSQLiteOpenHelper mOpenHelper; // person表的数据库帮助对象 static { uriMatcher = new UriMatcher(UriMatcher.NO_MATCH); // 添加一些uri(分机号) // content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/insert uriMatcher.addURI(AUTHORITY, "person/insert", PRESON_INSERT_CODE); // content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/delete uriMatcher.addURI(AUTHORITY, "person/delete", PERSON_DELETE_CODE); // content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/update uriMatcher.addURI(AUTHORITY, "person/update", PERSON_UPDATE_CODE); // content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/queryAll uriMatcher.addURI(AUTHORITY, "person/queryAll", PERSON_QUERY_ALL_CODE); // content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/query/# uriMatcher.addURI(AUTHORITY, "person/query/#", PERSON_QUERY_ITEM_CODE); } @Override public boolean onCreate() { mOpenHelper = new PersonSQLiteOpenHelper(getContext()); return true; } @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { SQLiteDatabase db = mOpenHelper.getReadableDatabase(); switch (uriMatcher.match(uri)) { case PERSON_QUERY_ALL_CODE: // 查询所有人的uri if(db.isOpen()) { Cursor cursor = db.query("person", projection, selection, selectionArgs, null, null, sortOrder); return cursor; // db.close(); 返回cursor结果集时, 不可以关闭数据库 } break; case PERSON_QUERY_ITEM_CODE: // 查询的是单条数据, uri末尾出有一个id if(db.isOpen()) { long id = ContentUris.parseId(uri); Cursor cursor = db.query("person", projection, "_id = ?", new String[]{id + ""}, null, null, sortOrder); return cursor; } break; default: throw new IllegalArgumentException("uri不匹配: " + uri); } return null; } @Override public String getType(Uri uri) { switch (uriMatcher.match(uri)) { case PERSON_QUERY_ALL_CODE: // 返回多条的MIME-type return "vnd.android.cursor.dir/person"; case PERSON_QUERY_ITEM_CODE: // 返回单条的MIME-TYPE return "vnd.android.cursor.item/person"; default: break; } return null; } @Override public Uri insert(Uri uri, ContentValues values) { switch (uriMatcher.match(uri)) { case PRESON_INSERT_CODE: // 添加人到person表中 SQLiteDatabase db = mOpenHelper.getWritableDatabase(); if(db.isOpen()) { long id = db.insert("person", null, values); db.close(); return ContentUris.withAppendedId(uri, id); } break; default: throw new IllegalArgumentException("uri不匹配: " + uri); } return null; } @Override public int delete(Uri uri, String selection, String[] selectionArgs) { switch (uriMatcher.match(uri)) { case PERSON_DELETE_CODE: // 在person表中删除数据的操作 SQLiteDatabase db = mOpenHelper.getWritableDatabase(); if(db.isOpen()) { int count = db.delete("person", selection, selectionArgs); db.close(); return count; } break; default: throw new IllegalArgumentException("uri不匹配: " + uri); } return 0; } @Override public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) { switch (uriMatcher.match(uri)) { case PERSON_UPDATE_CODE: // 更新person表的操作 SQLiteDatabase db = mOpenHelper.getWritableDatabase(); if(db.isOpen()) { int count = db.update("person", values, selection, selectionArgs); db.close(); return count; } break; default: throw new IllegalArgumentException("uri不匹配: " + uri); } return 0; } } 内容提供者访问和权限 <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.itheima28.othercontentprovider" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" /> <instrumentation android:name="android.test.InstrumentationTestRunner" android:targetPackage="com.itheima28.othercontentprovider" > </instrumentation> <uses-permission android:name="aa.bb.cc.read"/> <uses-permission android:name="aa.bb.cc.write"/> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <uses-library android:name="android.test.runner" /> <activity android:name="com.itheima28.othercontentprovider.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> package com.itheima28.othercontentprovider; import android.content.ContentResolver; import android.content.ContentUris; import android.content.ContentValues; import android.database.Cursor; import android.net.Uri; import android.test.AndroidTestCase; import android.util.Log; public class TextCase extends AndroidTestCase { private static final String TAG = "TextCase"; public void testInsert() { Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/insert"); // 内容提供者访问对象 ContentResolver resolver = getContext().getContentResolver(); ContentValues values = new ContentValues(); values.put("name", "fengjie"); values.put("age", 90); uri = resolver.insert(uri, values); Log.i(TAG, "uri: " + uri); long id = ContentUris.parseId(uri); Log.i(TAG, "添加到: " + id); } public void testDelete() { Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/delete"); // 内容提供者访问对象 ContentResolver resolver = getContext().getContentResolver(); String where = "_id = ?"; String[] selectionArgs = {"21"}; int count = resolver.delete(uri, where, selectionArgs); Log.i(TAG, "删除行: " + count); } public void testUpdate() { Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/update"); // 内容提供者访问对象 ContentResolver resolver = getContext().getContentResolver(); ContentValues values = new ContentValues(); values.put("name", "lisi"); int count = resolver.update(uri, values, "_id = ?", new String[]{"20"}); Log.i(TAG, "更新行: " + count); } public void testQueryAll() { Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/queryAll"); // 内容提供者访问对象 ContentResolver resolver = getContext().getContentResolver(); Cursor cursor = resolver.query(uri, new String[]{"_id", "name", "age"}, null, null, "_id desc"); if(cursor != null && cursor.getCount() > 0) { int id; String name; int age; while(cursor.moveToNext()) { id = cursor.getInt(0); name = cursor.getString(1); age = cursor.getInt(2); Log.i(TAG, "id: " + id + ", name: " + name + ", age: " + age); } cursor.close(); } } public void testQuerySingleItem() { Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/query/#"); // 在uri的末尾添加一个id content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/query/20 uri = ContentUris.withAppendedId(uri, 20); // 内容提供者访问对象 ContentResolver resolver = getContext().getContentResolver(); Cursor cursor = resolver.query(uri, new String[]{"_id", "name", "age"}, null, null, null); if(cursor != null && cursor.moveToFirst()) { int id = cursor.getInt(0); String name = cursor.getString(1); int age = cursor.getInt(2); cursor.close(); Log.i(TAG, "id: " + id + ", name: " + name + ", age: " + age); } } }

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