04_查看Android内存使用情况

1. 创建项目

1. Android清单文件

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.itheima28.memorydemo"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="8"

        android:targetSdkVersion="19" />

    <application

        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name="com.itheima28.memorydemo.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>

1. 布局文件

<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"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context="com.itheima28.memorydemo.MainActivity$PlaceholderFragment" >

    <TextView

        android:id="@+id/tv_memory_info"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_centerInParent="true"/>

</RelativeLayout>

1. 查询内存的代码

package com.itheima28.memorydemo;

import java.io.File;

import android.os.Bundle;

import android.os.Environment;

import android.os.StatFs;

import android.support.v7.app.ActionBarActivity;

import android.text.format.Formatter;

import android.widget.TextView;

public class MainActivity extends ActionBarActivity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.activity_main);

       TextView tvMemoryInfo = (TextView) findViewById(R.id.tv_memory_info);

       //获得sd卡的内存状态

       File sdcardFileDir = Environment.getExternalStorageDirectory();

       String sdcardMemory = getMemoryInfo(sdcardFileDir);

       //获得手机内部存储控件的状态

       File dataFileDir = Environment.getDataDirectory();

       String dataMemory = getMemoryInfo(dataFileDir);

       tvMemoryInfo.setText("SD卡: " + sdcardMemory + "\n手机内部: " + dataMemory);

    }

    /**

     * 根据路径获取内存状态

     * @param path

     * @return

     */

    @SuppressWarnings("deprecation")

    private String getMemoryInfo(File path) {

       //获得一个磁盘状态对象

       StatFs stat = new StatFs(path.getPath());

       //获得一个扇区的大小

       long blockSize = stat.getBlockSize();

       //获得扇区的总数

        long totalBlocks = stat.getBlockCount();

        //获得可用的扇区数量

        long availableBlocks = stat.getAvailableBlocks();

        //总空间

        String totalMemory =  Formatter.formatFileSize(this, totalBlocks * blockSize);

        //可用空间

        String availableMemory = Formatter.formatFileSize(this, availableBlocks * blockSize);

        return "总空间：" + totalMemory + "\n可用空间：" + availableMemory;

    }

}