android6.0的写入SD卡的权限申请

6.0的手机对于写入手机需要申请权限的我做了如下处理下面我贴出代码

package com.example.admin.sdapplication;import android.Manifest;import android.app.Dialog;import android.content.DialogInterface;import android.content.pm.PackageManager;import android.os.Build;import android.os.Bundle;import android.os.Environment;import android.support.annotation.NonNull;import android.support.v4.app.ActivityCompat;import android.support.v4.content.ContextCompat;import android.support.v7.app.AlertDialog;import android.support.v7.app.AppCompatActivity;import android.util.Log;import android.view.View;import android.widget.Button;import java.io.BufferedReader;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.InputStreamReader;public class SdkActivity extends AppCompatActivity implements View.OnClickListener{private Button btn_write;private Button btn_read;final int REQUEST_WRITE=1;//申请权限的请求码@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_sdk);btn_write= (Button) findViewById(R.id.btn_write);btn_read= (Button) findViewById(R.id.btn_read);btn_read.setOnClickListener(this);btn_write.setOnClickListener(this);}private void showAlert(){Dialog alertDialog = new AlertDialog.Builder(this).setTitle("权限说明").setMessage("我们需要这个权限给你提供存储服务").setIcon(R.drawable.ic_launcher).setPositiveButton("确定", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {// TODO Auto-generated method stub//2、申请权限: 参数二：权限的数组；参数三：请求码ActivityCompat.requestPermissions(SdkActivity.this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},REQUEST_WRITE);}}).setNegativeButton("取消", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {// TODO Auto-generated method stub}}).create();alertDialog.show();}@Overridepublic void onClick(View view) {switch (view.getId()){case R.id.btn_read:String s= readToSdCard();Log.i("readTosdCard",s);break;case R.id.btn_write://判断是否6.0以上的手机   不是就不用if(Build.VERSION.SDK_INT>=23){//判断是否有这个权限if(ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)!=PackageManager.PERMISSION_GRANTED){//第一请求权限被取消显示的判断，一般可以不写if (ActivityCompat.shouldShowRequestPermissionRationale(SdkActivity.this,Manifest.permission.WRITE_EXTERNAL_STORAGE)){Log.i("readTosdCard","我们需要这个权限给你提供存储服务");showAlert();}else {//2、申请权限: 参数二：权限的数组；参数三：请求码ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},REQUEST_WRITE);}}else {writeToSdCard();}} else{writeToSdCard();}break;}}//写数据public void writeToSdCard(){//1、判断sd卡是否可用if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){//sd卡可用//2、获取sd卡路径File sdFile=Environment.getExternalStorageDirectory();File path=new File(sdFile,"a.txt");//sd卡下面的a.txt文件  参数 前面 是目录 后面是文件try {FileOutputStream fileOutputStream=new FileOutputStream(path);fileOutputStream.write("hello".getBytes());} catch (Exception e) {e.printStackTrace();}}}//读数据public String readToSdCard(){StringBuilder stringBuilder = null;if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){File sdFile=Environment.getExternalStorageDirectory();File path=new File(sdFile,"a.txt");stringBuilder =new StringBuilder();try {FileInputStream fileInputStream=new FileInputStream(path);BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(fileInputStream));String str;while ((str=bufferedReader.readLine())!=null){stringBuilder.append(str);}} catch (Exception e) {e.printStackTrace();}}return  stringBuilder.toString();}//判断授权的方法  授权成功直接调用写入方法  这是监听的回调//参数  上下文   授权结果的数组   申请授权的数组@Overridepublic void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {super.onRequestPermissionsResult(requestCode, permissions, grantResults);if(requestCode==REQUEST_WRITE&&grantResults[0]== PackageManager.PERMISSION_GRANTED){writeToSdCard();}}}

其实就是判断是不是6.0的手机再进行申请权限的处理 利用申请权限的回调机制直接在权限申请下来之后调用写入处理注释很清楚 你们看看代码就好了( ⊙ o ⊙ )！另外需要注意的一点我们也处理了第一次用户拒绝权限，第二次需要请求时，给用户提示权限作用

//第一请求权限被取消显示的判断，一般可以不写if (ActivityCompat.shouldShowRequestPermissionRationale(SdkActivity.this,Manifest.permission.WRITE_EXTERNAL_STORAGE)){Log.i("readTosdCard","我们需要这个权限给你提供存储服务");showAlert();}else {//2、申请权限: 参数二：权限的数组；参数三：请求码ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},REQUEST_WRITE);}