004_01获取SD容量

package com.example.sdcard;

import java.io.File;

import android.app.Activity;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.os.StatFs;
import android.text.format.Formatter;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;

public class MainActivity extends Activity {

    private long blockSize;
    private long totalBlocks;
    private long availableBlocks;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        TextView tv_available = (TextView) findViewById(R.id.tv_available);
        TextView tv_total =(TextView) findViewById(R.id.tv_total);
        
        File path = Environment.getExternalStorageDirectory();
        StatFs stat = new StatFs(path.getPath());
        
        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();
        }
        
        //tv_available.setText(availableBlocks * blockSize + "/byte");
        //tv_total.setText(totalBlocks * blockSize + "/byte");
        
        String sdavail = formatSize(availableBlocks * blockSize);
        String sdtotal = formatSize(totalBlocks * blockSize);
        tv_available.setText(sdavail);
        tv_total.setText(sdtotal);
        
    }
    private String formatSize(long size){
        return Formatter.formatFileSize(this, size);
    }
}