Androidx学习笔记（13）-- 获取sd卡剩余容量的代码

获取sd卡剩余容量的代码

导入Settings项目查找“可用空间”得到

<stringname="memory_available"msgid="418542433817289474">"可用空间"</string>

查找"memory_available"，得到

<Preferenceandroid:key="memory_sd_avail"
style="?android:attr/preferenceInformationStyle"
android:title="@string/memory_available"
android:summary="00"/>

查找"memorysdavail"，得到

//这个字符串就是sd卡剩余容量
formatSize(availableBlocks*blockSize)+readOnly
//这两个参数相乘，得到sd卡以字节为单位的剩余容量
availableBlocks*blockSize

存储设备会被分为若干个区块，每个区块有固定的大小区块大小*区块数量等于存储设备的总大小

importjava.io.File;

importandroid.os.Build;

importandroid.os.Bundle;

importandroid.os.Environment;

importandroid.os.StatFs;

importandroid.app.Activity;

importandroid.text.format.Formatter;

importandroid.view.Menu;

importandroid.widget.TextView;

publicclassMainActivityextendsActivity{

@SuppressWarnings("deprecation")

@Override

	protectedvoidonCreate(BundlesavedInstanceState){

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

Filepath=Environment.getExternalStorageDirectory();

StatFsstat=newStatFs(path.getPath());

longblockSize;

longtotalBlocks;

longavailableBlocks;

//获取当前系统版本的等级VERSION_CODES.JELLY_BEAN_MR24.3开始可以使用

if(Build.VERSION.SDK_INT>=Build.VERSION_CODES.JELLY_BEAN_MR2){

	blockSize=stat.getBlockSizeLong();

totalBlocks=stat.getBlockCountLong();

availableBlocks=stat.getAvailableBlocksLong();

}

else{

	blockSize=stat.getBlockSize();

totalBlocks=stat.getBlockCount();

availableBlocks=stat.getAvailableBlocks();

}

TextViewtv=(TextView)findViewById(R.id.tv);

tv.setText(formatSize(availableBlocks*blockSize));

}

	privateStringformatSize(longsize){

returnFormatter.formatFileSize(this,size);

}

}