onNewIntent中的progressDialog

Question

我在扫描NFC标签时正在使用onNewIntent。我想在扫描标签时显示ProgressDialog。我尝试使用一个线程，但它崩溃了我的应用程序。在onNewIntent启动时，有什么方法可以显示progressDialog吗？

public void onNewIntent(Intent intent) {
        setIntent(intent);
        Thread scanning = new Thread(new Runnable() {
            public void run() {
                ScanDialog = ProgressDialog.show(BorrowActivity.this,
                        "Scanning...", "scanning");
            }
        });
        scanning.start();
              .
              . //next code doing something
              .
}

Answer 1

您无法在其他线程上更新或使用UI：

<强>溶液

调用主线程并更新其中的UI

    Thread scanning = new Thread(new Runnable() {
        public void run() {
            runOnUiThread(new Runnable() 
            {
               public void run() 
               {
                    ScanDialog = ProgressDialog.show(BorrowActivity.this,
                        "Scanning...", "scanning");
               }
            });

        }
 });

Answer 2

最后我用asyncTask修复了它。

public void onNewIntent(Intent intent) {
    setIntent(intent);
        ScanDialog = ProgressDialog.show(BorrowActivity.this,
                "Scanning...", "Scanning");

        try {
        new DoBackgroundTask().execute();
        } catch (Exception e) {
             //error catch here
        }
        ScanDialog.dismiss();

和AsyncTask：

private class DoBackgroundTask extends AsyncTask<Integer, String, Integer> {

    protected Integer doInBackground(Integer... status) {
     //do something
    }
    protected void onProgressUpdate(String... message) {
    }
    protected void onPostExecute(Integer status) {
    }
}