如何在用户单击 android 时取消下载

how to cancel a download when user clicked in android

我是 android 的下载管理器方面的新手,当用户单击按钮时我无法取消下载,我正在输入请求的当前 ID 但仍然没有解决它,请帮助我进步 这是主要的 class

 public class DownloadManagerActivity extends Activity {
    private long enqueue; private DownloadManager dm; private long     downloadReference; Query query; Cursor c; String action;
long downloadId;
Request request;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    BroadcastReceiver receiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            action = intent.getAction();
            if (DownloadManager.ACTION_DOWNLOAD_COMPLETE.equals(action)) {
                downloadId = intent.getLongExtra(
                        DownloadManager.EXTRA_DOWNLOAD_ID, 0);
                query = new Query();
                query.setFilterById(enqueue);
                c = dm.query(query);
                if (c.moveToFirst()) {
                    int columnIndex = c
                            .getColumnIndex(DownloadManager.COLUMN_STATUS);
                    //
                    if (DownloadManager.STATUS_SUCCESSFUL == c.getInt(columnIndex)) {
                        Toast.makeText(DownloadManagerActivity.this, "Download Complete", Toast.LENGTH_LONG).show();

                    }


                }
            }
        }
    };

    registerReceiver(receiver, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE));
}

public void onClick(View view) {
    dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
    request = new Request(Uri.parse("http://192.168.10.6/mytv/mashup.mp4"));
    enqueue = dm.enqueue(request);

}

public void showDownload(View view) {
    Intent i = new Intent();
    i.setAction(DownloadManager.ACTION_VIEW_DOWNLOADS);
    startActivity(i);
}

public void cancelDownload(View view) {
    //downloadReference= intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, 0);
    downloadReference = dm.enqueue(request);
    dm.remove(downloadReference);

    Toast.makeText(DownloadManagerActivity.this, "Download Cancelled", Toast.LENGTH_SHORT).show();

}

downloadReference = dm.enqueue(request) 创建一个新任务并且 return 一个新的 id.You 应该使用以前的 ID。

public void cancelDownload(View view) {
    //downloadReference= intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, 0);
    //downloadReference = dm.enqueue(request);
    dm.remove(enqueue );

    Toast.makeText(DownloadManagerActivity.this, "Download Cancelled", Toast.LENGTH_SHORT).show();

}