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;

}

}