小编Bis*_*iaz的帖子

由于我是 Android 开发的新手，我正在尝试使用 DownloadManager 来简化应用程序。

这是代码

public class MainActivity extends AppCompatActivity implements ActivityCompat.OnRequestPermissionsResultCallback{

Button btn;

private long referenceID;
private DownloadManager downloadManager;
private static final int PERMISSION_REQUEST_CODE = 1;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    btn = findViewById(R.id.btn);

    btn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {



            if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){


                if (checkPermission())
                {

                    /*** If Storage Permission Is Given, Check External storage is available for read and write***/

                    Uri image_uri = Uri.parse("https://unifiedclothes.com/Unifiedclothes/App_Gallery/thumb_8_121432471036-1432471036-SC-505.jpg");

                    referenceID = DownloadImage(image_uri);




                } else {

                    requestPermission(); …