public class SDCardDemo extends AppCompatActivity implements View.OnClickListener {
private static final String TAG = "SDCardDemo";
private Button btn_sd_card;
private Button btn_check_sd_card_state;
private Button btn_check_sd_card_free;
private static final int REQUEST_EXTERNAL_STORAGE = 1;
private static String[] PERMISSIONS_STORAGE = {
"android.permission.READ_EXTERNAL_STORAGE",
"android.permission.WRITE_EXTERNAL_STORAGE" };
@RequiresApi(api = Build.VERSION_CODES.M)
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sdcard_demo);
verifyStoragePermissions(this);
initView();
setListener();
}
private void setListener(){
btn_sd_card.setOnClickListener(this);
btn_check_sd_card_state.setOnClickListener(this);
btn_check_sd_card_free.setOnClickListener(this);
}
private void initView(){
btn_sd_card = findViewById(R.id.btn_sd_card);
btn_check_sd_card_state = findViewById(R.id.btn_check_sd_card_state);
btn_check_sd_card_free = findViewById(R.id.btn_check_sd_card_free);
}
public static void verifyStoragePermissions(Activity activity) {
try {
//检测是否有写的权限
int permission = ActivityCompat.checkSelfPermission(activity,
"android.permission.WRITE_EXTERNAL_STORAGE");
if (permission != PackageManager.PERMISSION_GRANTED) {
// 没有写的权限,去申请写的权限,会弹出对话框
ActivityCompat.requestPermissions(activity, PERMISSIONS_STORAGE,REQUEST_EXTERNAL_STORAGE);
}
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void onClick(View v) {
File filepath = Environment.getExternalStorageDirectory();
switch (v.getId()){
case R.id.btn_sd_card:
Log.d(TAG, filepath.toString());
File file = new File(filepath,"info.text");
try {
FileOutputStream fileOutputStream = new FileOutputStream(file);
fileOutputStream.write("www.baidu.com".getBytes());
fileOutputStream.close();
Toast.makeText(SDCardDemo.this,"sd卡写入数据成功",Toast.LENGTH_SHORT).show();
} catch (Exception e) {
e.printStackTrace();
}
break;
case R.id.btn_check_sd_card_state:
String state = Environment.getExternalStorageState();
if(state.equals(Environment.MEDIA_MOUNTED))
{
Toast.makeText(this,"sdcard已经挂载",Toast.LENGTH_SHORT).show();
}
if(state.equals(Environment.MEDIA_UNMOUNTED))
{
Toast.makeText(this,"sdcard已经取消挂载",Toast.LENGTH_SHORT).show();
}
break;
case R.id.btn_check_sd_card_free:
long freeSpace = filepath.getFreeSpace();
String s = Formatter.formatFileSize(this, freeSpace);
Toast.makeText(this,s, Toast.LENGTH_LONG).show();
break;
}
}
}
在androidManifest也加了:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
动态权限检查也加了,还是报错:
D/SDCardDemo: /storage/emulated/0
W/System.err: java.io.FileNotFoundException: /storage/emulated/0/info.text: open failed: EACCES (Permission denied)
at libcore.io.IoBridge.open(IoBridge.java:496)
at java.io.FileOutputStream.<init>(FileOutputStream.java:235)
at java.io.FileOutputStream.<init>(FileOutputStream.java:186)
at com.example.qqlogindemo.SDCardDemo.onClick(SDCardDemo.java:77)
你好请问这个问题最后解决了吗