什么是广播

广播是Android SDK的四大组件中唯一需要别动接收数据的组件。也就是说对于Activity、ContentProvider和Service都可以主动调用，并获取返回数据。而负责接收Broadcast数据的接收器却永远不知道什么时候可以接收到广播。从这种表现形式上看，很像面向对象中的事件（Event），对于事件（onClick、onKeydown）来说，从来不会预知用户什么时候触发他们，只能默默的等待不可预知的事件发生。因此，广播也可以被成为全局事件。

接收系统广播

短信拦截（静态注册）

1 编写广播接收器类，继承自android.content.BroadcastReceiver类

ShortMessageReceiver.java

package com.turing.base.activity.broadcastDemo;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.telephony.SmsMessage;
import android.widget.Toast;
import com.apkfuns.logutils.LogUtils;
import java.util.Set;
public class ShortMessageReceiver extends BroadcastReceiver {
    private Handler handler ;
    public ShortMessageReceiver() {
    }
    public ShortMessageReceiver(Handler handler) {
        this.handler = handler ;
    }
    @Override
    public void onReceive(Context context, Intent intent) {
        Bundle bundle = intent.getExtras();
        if (bundle != null) {
            Set<String> keys = bundle.keySet();
            //查看收的广播包含哪些数据
            for (String key : keys) {
                LogUtils.e("bundele中的数据" + key);
            }
            // 获取收到的短信
            Object[] objArray = (Object[]) bundle.get("pdus");
            String message = parseMessageFromRawData(objArray);
            Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
            Message msg = new Message();
            msg.what = 1 ;
            msg.obj = message;
            handler.sendMessage(msg);
            /**
            // 定义封装短信内容的SmsMessage对象数组
            SmsMessage[] message = new SmsMessage[objArray.length];
            // 循环处理收到的所有短信
            for (int i = 0; i < objArray.length; i++) {
                // 将每条短信数据转换成SendMessage对象
                message[i] = SmsMessage.createFromPdu((byte[]) objArray[i]);
                // 获取发送短信的电话号码和短信内容
                String messageInfo = "手机号：" + message[i].getOriginatingAddress() + "\n";
                messageInfo += "短信内容：" + message[i].getDisplayMessageBody();
                //做个简单的展示
                Toast.makeText(context, messageInfo, Toast.LENGTH_SHORT).show();
            }
             **/
        }
    }
    public  String  parseMessageFromRawData(Object[] pdus) {
        if (pdus == null) return null;
        try {
            StringBuilder message = new StringBuilder();
            for (Object pdu : pdus) {
                SmsMessage smsMessage = SmsMessage.createFromPdu((byte[]) pdu);
                if (smsMessage == null) continue;
                message.append("源号码:" + smsMessage.getOriginatingAddress() + ",内容:" +smsMessage.getDisplayMessageBody());
            }
            return message.toString();
        } catch (Exception e) {
            LogUtils.e( "SMSBroadcastReceiver read sms failed", e);
        } catch (OutOfMemoryError oom) {
            LogUtils.e( "SMSBroadcastReceiver caused OOM =_=!", oom);
            //为了避免后续操作出现问题，gc一下
            System.gc();
            System.gc();
        }
        return null;
    }
}

清单文件配置Receiver

 <receiver
            android:name=".activity.broadcastDemo.ShortMessageReceiver"
            android:enabled="true"
            android:exported="true">
            <intent-filter>
                <action android:name="android.provider.Telephony.SMS_RECEIVED" />
            </intent-filter>
        </receiver>

清单文件配置权限

<uses-permission android:name="android.permission.RECEIVE_SMS" />

注意事项

如果不知道广播中包含哪些数据，可以从Bundle.keySet()方法中获取这些数据的key，将其输出到Logcat中查看，如上述代码所示
由于接受的短信内容是以字节数组的形式保存的，为了方便使用这些数据，需要使用SmsMessage.createFromPdu方法将这些字节数据组成的数据转换为SmsMessage对象
SmsMessage建议使用android.telephony.SmsMessage中的。
由于接收器可能接收多条短信，因此通过pdus返回了一个短信数组。
必须要指定<action android:name="android.provider.Telephony.SMS_RECEIVED" /> 我们编写的短信接收器才可以接收系统的短信广播，切记
配置权限android.permission.RECEIVE_SMS
即使注册广播接收器的程序关闭，接收器仍然会接收到广播，除非从模拟器或者手机中卸载程序或者注销接收器，否则无法阻止接收器接收广播

用代码注册广播接收器

如果在清单文件中配置广播接收器，程序安装后就会自动注册广播接收器，如果想在适当的时候注册广播接收器，在使用完成之后将其注销就需要使用Java代码来操作了。

注册和取消方法

注册广播接收器的方法是 registerReceiver，注销的方法是unregisterReceiver，定义如下：

 public Intent registerReceiver(
        BroadcastReceiver receiver, IntentFilter filter)
 public void unregisterReceiver(BroadcastReceiver receiver)

其中receiver表示广播接收器对象，

filter参数相当于设置intent-filter标签中的内容。

Code

package com.turing.base.activity.broadcastDemo;
import android.app.Activity;
import android.content.IntentFilter;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import com.turing.base.R;
public class SmsMessageAct extends Activity implements View.OnClickListener {
    private EditText et_phone, et_msg;
    private Button btn_registerReceiver, btn_unRegisterReceiver;
    private ShortMessageReceiver shortMessageReceiver;
    private Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            switch (msg.what) {
                case 1:
                    String message = (String) msg.obj;
                    String pre = "源号码:";
                    String suf = ",内容:";
                    et_phone.setText(message.substring((message.indexOf(pre) + pre.length()), message.indexOf(suf)));
                    et_msg.setText(message.substring(message.indexOf(suf) + suf.length(), message.length()));
                    break;
                default:
                    break;
            }
        }
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_sms_message);
        initView();
        initEvents();
        // 创建广播接收器的对象
        shortMessageReceiver = new ShortMessageReceiver(handler);
    }
    private void initEvents() {
        btn_registerReceiver.setOnClickListener(this);
        btn_unRegisterReceiver.setOnClickListener(this);
    }
    private void initView() {
        et_phone = (EditText) findViewById(R.id.id_et_phone);
        et_msg = (EditText) findViewById(R.id.id_et_msg);
        btn_registerReceiver = (Button) findViewById(R.id.id_btn_registerReceiver);
        btn_unRegisterReceiver = (Button) findViewById(R.id.id_btn_unRegisterReceiver);
    }
    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.id_btn_registerReceiver:
                registerReceiver(shortMessageReceiver, new IntentFilter("android.provider.Telephony.SMS_RECEIVED"));
                Toast.makeText(this, "动态注册广播接收器成功", Toast.LENGTH_SHORT).show();
                break;
            case R.id.id_btn_unRegisterReceiver:
                unregisterReceiver(shortMessageReceiver);
                Toast.makeText(this, "动态注销短信广播接收器over", Toast.LENGTH_SHORT).show();
                break;
            default:
                break;
        }
    }
    @Override
    protected void onPause() {
        super.onPause();
        if (shortMessageReceiver != null) {
            unregisterReceiver(shortMessageReceiver);
            Toast.makeText(this, "Activity onPause ,注销短信广播接收器over", Toast.LENGTH_SHORT).show();
        }
    }
}

广播的优先级

android:priority

通过intent-filter标签的android:priority属性可以设置接收器的调用优先级，该属性值属于一个整数，数值越大，优先级越高。

Code

 <receiver android:name=".activity.service.StartupReceiver">
            <intent-filter android:priority="100">
                <action android:name="android.intent.action.BOOT_COMPLETED" />
            </intent-filter>
        </receiver>

如果不设置优先级别，对于同一个应用程序中的广播接收器会按照在Manifest清单文件中定义的顺序调用。

广播的优先级只是对同步处理方式起作用，如果在接收器中使用了异步处理方式，则调用的顺序除了和优先级有关，还和Android系统的线程调用有关。

来去电拦截

广播动作

监听电话状态以用于拦截来去电，来电（监听电话状态）和去电的广播动作如下：

来电：android.intent.action.PHONE_STATE

去电：android.intent.action.NEW_OUTGOING_CALL

来电可以分解为3个状态：未接电话时的响铃，接听电话和挂断电话（可能是对方挂断，也可能是自己挂断）

监听这三个状态的代码如下（使用静态方式注册的广播）：

CallInReceiver：

package com.turing.base.activity.broadcastDemo;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.telephony.TelephonyManager;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.PopupWindow;
import android.widget.TextView;
import android.widget.Toast;
import com.turing.base.R;
public class CallInReceiver extends BroadcastReceiver {
    private static Object obj;
    public CallInReceiver() {
    }
    @Override
    public void onReceive(Context context, Intent intent) {
        // 获取电话管理服务，以便获取电话的状态
        TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
        switch (telephonyManager.getCallState()) {
            case TelephonyManager.CALL_STATE_RINGING: // 响铃
                String incomingNumber = intent.getStringExtra("incoming_number");
                Toast.makeText(context, "电话响铃中......", Toast.LENGTH_SHORT).show();
                //showPopupWindowToast(context,incomingNumber);
                break;
            case TelephonyManager.CALL_STATE_OFFHOOK: //接听电话
                Toast.makeText(context, "电话已接通......", Toast.LENGTH_SHORT).show();
                break;
            case TelephonyManager.CALL_STATE_IDLE:// 挂断电话
                Toast.makeText(context, "挂断电话......", Toast.LENGTH_SHORT).show();
                //closeToast();
            default:
                break;
        }
    }
    /**
     * 使用反射，此Toast不会关闭
     *
     * @param context
     * @param msg
     */
//    public static void showToast(Context context, String msg) {
//        Toast toast = Toast.makeText(context, msg, Toast.LENGTH_SHORT);
//        toast.setGravity(Gravity.TOP | Gravity.CENTER_HORIZONTAL, 0, 0);
//        try {
//            Field field = toast.getClass().getDeclaredField("mTN");
//            field.setAccessible(true);
//            obj = field.get(toast);
//            Method method = obj.getClass().getDeclaredMethod("show", null);
//            method.invoke(obj, null);
//        } catch (Exception e) {
//        }
//
//    }
    /**
     * 通过此方法关闭那个不可关闭的Toast
     */
//    public static void closeToast() {
//        if (obj != null) {
//            try {
//                Method method = obj.getClass().getDeclaredMethod("hide", null);
//                method.invoke(obj, null);
//            } catch (Exception e) {
//            }
//
//        }
//    }
    public static void showPopupWindowToast(Context context, String incomingNumber) {
        LayoutInflater inflater  = LayoutInflater.from(context);
        View view = inflater.inflate(R.layout.activity_popupwd_toast, null);
        TextView textView = (TextView)view.findViewById(R.id.tvMsg);
        textView.setText("电话号码：" + incomingNumber);
        final PopupWindow popupWindow = new PopupWindow(view,500 ,100);
        popupWindow.setTouchable(false);
        popupWindow.showAtLocation(view, Gravity.CENTER_HORIZONTAL,20 ,0);
        // 设置定时器，5秒后自动关闭
        android.os.Handler handler = new android.os.Handler();
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                popupWindow.dismiss();
            }
        } , 5*1000);
    }
}

CallOutReceiver

package com.turing.base.activity.broadcastDemo;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;
public class CallOutReceiver extends BroadcastReceiver {
    public CallOutReceiver() {
    }
    @Override
    public void onReceive(Context context, Intent intent) {
        // 获取去电号码
        String outComingNumber = intent.getStringExtra(Intent.EXTRA_PHONE_NUMBER);
        // showToast
        Toast.makeText(context, "去电......" + outComingNumber, Toast.LENGTH_SHORT).show();
        //CallInReceiver.showPopupWindowToast(context, outComingNumber);
    }
}

 <!-- 来电 -->
        <receiver
            android:name=".activity.broadcastDemo.CallInReceiver"
            android:enabled="true"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.PHONE_STATE" />
            </intent-filter>
        </receiver>
        <!-- 去电 -->
        <receiver
            android:name=".activity.broadcastDemo.CallOutReceiver"
            android:enabled="true"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.NEW_OUTGOING_CALL" />
            </intent-filter>
        </receiver>

设置权限

  <uses-permission android:name="android.permission.READ_PHONE_STATE" />
    <uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS" />

截获屏幕休眠与唤醒

按手机上的挂断按钮后，手机会进入休眠状态（屏幕变黑），当再此按下手机的任意键后，屏幕会唤醒（屏幕变量）。这两个动作可以通过如下两个动作连接

广播动作

休眠状态 Intent.ACTION_SCREEN_OFF
唤醒状态 Intent.ACTION_SCREEN_ON

 private void screenOnOff() {
        ScreenOnOffReceiver screenOnOffReceiver = new ScreenOnOffReceiver();
        IntentFilter intentFilter = new IntentFilter();
        // 设置屏幕唤醒广播的动作
        intentFilter.addAction(Intent.ACTION_SCREEN_ON);
        // 设置屏幕休眠广播的动作
        intentFilter.addAction(Intent.ACTION_SCREEN_OFF);
        // 注册
        registerReceiver(screenOnOffReceiver,intentFilter);
    }

package com.turing.base.activity.broadcastDemo;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
public class ScreenOnOffReceiver extends BroadcastReceiver {
    public ScreenOnOffReceiver() {
    }
    @Override
    public void onReceive(Context context, Intent intent) {
        // 接收屏幕唤醒状态的广播
        if (Intent.ACTION_SCREEN_ON.equals(intent.getAction())) {
            Log.d("screen", "ok");
        } else if (Intent.ACTION_SCREEN_OFF.equals(intent.getAction())) {
            Log.d("screen", "off");
        }
    }
}

注意事项：

屏幕唤醒和休眠的广播，只能通过代码的以动态的方式注册，如果在清单文件中配置，则不起作用。

开机自动运行

广播动作

android.intent.action.BOOT_COMPLETED

Code

package com.turing.base.activity.service;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import com.apkfuns.logutils.LogUtils;
/**
 * 只要完成两项工作： 启动服务 和 显示一个Activity提示服务启动成功(主题设置为Dialog的形式)
 */
public class StartupReceiver extends BroadcastReceiver {
    public StartupReceiver() {
    }
    @Override
    public void onReceive(Context context, Intent intent) {
        LogUtils.e("StartupReceiver  onReceive");
        // 如果是开机启动的Action
        if(intent.getAction().equals(Intent.ACTION_BOOT_COMPLETED)){
            // 启动Activity
            Intent activityIntent = new Intent(context,BootCompletedMessageAct.class);
            // 想要在Service中启动Activity，必须设置如下标志
            activityIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            context.startActivity(activityIntent);
            //启动服务
            Intent serviceIntent = new Intent(context,StartupService.class);
            context.startService(serviceIntent);
        }
    }
}

  <!-- 开机广播 -->
        <receiver android:name=".activity.service.StartupReceiver">
            <intent-filter >
                <action android:name="android.intent.action.BOOT_COMPLETED" />
            </intent-filter>
        </receiver>

显示手机电池的当前电量

查看电池的电量也需要接收一个系统广播，本demo是通过registerReceiver方法进行注册的。

广播动作

Intent.ACTION_BATTERY_CHANGED

Code

package com.turing.base.activity.broadcastDemo;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;
import com.turing.base.R;
public class BatteryInfoAct extends AppCompatActivity {
    private TextView tv_batteryInfo;
    private BroadcastReceiver batteryChangedReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            if (Intent.ACTION_BATTERY_CHANGED.equals(intent.getAction())) {
                //level标识当前电量的值
                int level = intent.getIntExtra("level", 0);
                // scale标识电量的总刻度
                int scale = intent.getIntExtra("scale", 100);
                // 将当前电量换算成百分比的形式
                tv_batteryInfo.setText("电池用量：" + (level * 100 / scale) + "%");
            }
        }
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_battery_info);
        tv_batteryInfo = (TextView) findViewById(R.id.id_tv_battery);
        // 注册广播
        registerReceiver(batteryChangedReceiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
    }
    @Override
    protected void onPause() {
        super.onPause();
        if (batteryChangedReceiver != null) {
            unregisterReceiver(batteryChangedReceiver);
        }
    }
}

发送广播

sendBoradcast

可以通过sendBoradcast的方式发送广播

方法定义如下：

public void sendBroadcast(Intent intent)

下面的代码发送了一个广播，并添加了广播数据和category

// 指定广播动作
Intent brdcstIntent= new Intent("com.turing.demo.sendbrdcst.MYBROADCAST");
// 添加category
brdcstIntent.addCategory("xxx.xxx.xxx");
// 设置广播数据
brdcstIntent.putExtra("name","XXXXX");
// 发送广播
sendBoradcast(brdcstIntent);

Code

两个工程，proj_send_broadcast, proj_custom_receiver

proj_send_broadcast

public class Main extends Activity
{
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
    public void onClick_Send_Broadcast(View view)
    {
        Intent broadcastIntent = new Intent("mobile.android.ch10.MYBROADCAST");
        broadcastIntent.addCategory("mobile.android.ch10.mycategory");
        broadcastIntent.putExtra("name", "broadcast_data");
        sendBroadcast(broadcastIntent);
        Toast.makeText(this, "广播发送成功.", Toast.LENGTH_LONG).show();
    }
}

proj_custom_receiver

CustomReceiver

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;
public class CustomReceiver extends BroadcastReceiver
{
    @Override
    public void onReceive(Context context, Intent intent)
    {
        if ("mobile.android.ch10.MYBROADCAST".equals(intent.getAction()))
        {
            String name = intent.getStringExtra("name");
            Toast.makeText(context, name, Toast.LENGTH_LONG).show();
        }
    }
}

清单文件

    <receiver android:name=".CustomReceiver">
            <intent-filter>
                <action android:name="mobile.android.ch10.MYBROADCAST" />
                <category android:name="mobile.android.ch10.mycategory" />
            </intent-filter>
        </receiver>

验证广播接收器是否注册

 private void validateReceiver(String actionName) {
        // 获取PackageManager
        PackageManager packageManager = getPackageManager();
        // 指定要查询广播的动作
        Intent intent = new Intent(actionName);
        // 返回已查到的广播接收器集合,如果没有符合条件的广播,List长度为0
        List<ResolveInfo> resolveInfos = packageManager.queryBroadcastReceivers(intent,PackageManager.GET_INTENT_FILTERS);
        // 显示查询到的广播的数量
        Toast.makeText(this,"已发现" + resolveInfos.size() + "个接收去电广播的接收器" ,Toast.LENGTH_SHORT).show();
        StringBuilder sb = new StringBuilder();
        if(resolveInfos.size() > 0 ){
            for (ResolveInfo resolveInfo : resolveInfos){
                sb.append(resolveInfo.toString());
            }
        }
        Toast.makeText(this,sb.toString() ,Toast.LENGTH_SHORT).show();
    }

全局事件-广播（Broadcast）

什么是广播

接收系统广播

短信拦截（静态注册）

1 编写广播接收器类，继承自android.content.BroadcastReceiver类

清单文件配置Receiver

清单文件配置权限

注意事项

用代码注册广播接收器

注册和取消方法

Code

广播的优先级

android:priority

Code

来去电拦截

广播动作

截获屏幕休眠与唤醒

广播动作

注意事项：

开机自动运行

广播动作

Code

显示手机电池的当前电量

广播动作

Code

发送广播

sendBoradcast

Code

proj_send_broadcast

proj_custom_receiver

CustomReceiver

清单文件

验证广播接收器是否注册

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