1.在AndroidManifest.xml文件中添加以下权限:
2.在代码中使用以下代码尝试访问SD卡目录中的文件:
if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())) { File sdcardDir = Environment.getExternalStorageDirectory(); String path = sdcardDir.getPath() + "/文件夹名/文件名"; File file = new File(path); if (file.exists()) { //实现读取操作 } }
3.在Android 6.0及以上版本中,需要动态获取权限,在代码中添加以下代码:
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { if (checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) { requestPermissions(new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, PERMISSION_REQUEST_STORAGE); return; } }
4.在Activity中重写onRequestPermissionsResult方法获取权限:
@Override public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { super.onRequestPermissionsResult(requestCode, permissions, grantResults); switch (requestCode) { case PERMISSION_REQUEST_STORAGE: if (grantResults[0] == PackageManager.PERMISSION_GRANTED) { //已授权,执行读取操作 } else { //未授权,禁止读取操作 } break; default: break; } }