// Storage Permissions
private static final int REQUEST_EXTERNAL_STORAGE = 1;
private static String[] PERMISSIONS_STORAGE = {
        Manifest.permission.READ_EXTERNAL_STORAGE,
        Manifest.permission.WRITE_EXTERNAL_STORAGE
};
// Check if we have write permission
int permission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE);
if
 
 (permission != PackageManager.PERMISSION_GRANTED) {
   // We don't have permission so prompt the user
   ActivityCompat.requestPermissions(
       activity,
       PERMISSIONS_STORAGE,
       REQUEST_EXTERNAL_STORAGE
     );
 }

在清單檔案中新增許可權：

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"
 
 />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>