markdown 的android动态权限检查与申请

Posted 2021-05-06

资源清单文件中添加
```
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
```
使用时,检查权限,返回boolean值
```[java]
ContextCompat.checkSelfPermission(this,
                Manifest.permission.WRITE_EXTERNAL_STORAGE)==PackageManager.PERMISSION_GRANTED;
```
false需要申请权限
```
ActivityCompat.requestPermissions(this,
                new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 35715);
```
申请权限后需要定义监听权限申请结果事件
```[java]
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    switch (requestCode) {
        case 35715: {
            // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                startDownloadFile();
            } else {
                Toast.makeText(this, "Permission denied!", Toast.LENGTH_SHORT).show();
                // permission denied, boo! Disable the
                // functionality that depends on this permission.
            }
            return;
        }
    }
}
```