App Using Asynctask Still Hogging The Ui Thread?

I've written an app that sits in the 'Share via' menu (for quickly emailing myself links to things I find on the web or look at in RSS readers) For this I'm using an intent.action.

Solution 1:

ANSWER?... I've massively simplified the above code to try to work out what might be wrong. I created a bog standard App and used the following:

package uk.co.baroquedub.testcheck;

import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;

import android.widget.Toast;

publicclassMainActivityextendsActivity {

@OverrideprotectedvoidonCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    doSendTask task = newdoSendTask();
    task.execute(newString[] { "urlString" });
}

protectedvoid showDialog (String response){
    Toast.makeText(this, response, Toast.LENGTH_SHORT).show();
    finish();
}

privateclassdoSendTaskextendsAsyncTask<String, Void, String> {
    @OverrideprotectedStringdoInBackground(String... urls) {
      String response = "";

      try { 
          Thread.sleep(5000);
          response = "Waited";
      }
      catch (InterruptedException ex) {  }

      return response;
    }

    @OverrideprotectedvoidonPostExecute(String result) {
            showDialog(result);
    }
}

}

This has allowed me to see what's going wrong: my app is opening on top of the browser (a white screen appears with a title bar showing the name of the app) I wasn't aware of this with my proper app (above) because I was using a Theme that used a transparent background.

See: screencast for demo of problem

So although the email is being sent as an AsyncTask, while this is happening the app itself is appearing on top of the browser - which is what is stopping it from being accessible. (I'll post a request for help on this as a separate question)

Solution 2:

No, AsyncTask is not bond to your UI thread and you will not be blocking it as you did while doing some lengthy operation in your onCreate().

Solution 3:

I think you have a mistake in your code:

doSendTasktask=newdoSendTask();
 task.execute(url); // if you want to put more urls  task.execute(url,url1,url2);try {
        sender.sendMail(subjectText,   
                url[0],             // get the first url
                  senderEmail,   
                  recipientEmail);
            response = "Email sent";
        } catch (Exception e) {
            //Log.e("SendMail", e.getMessage(), e); 
            response = "Error sending email";
        }

Solution 4:

ASyncTasks are, indeed, executed on their own thread, as written on their reference page.

When you create the intent for this activity, you pass the flag 'FLAG_ACTIVITY_CLEAR_TOP', which reads something like '...all of the other activities on top of it will be closed and this Intent will be delivered to the (now on top) old activity as a new Intent.'. Doesn't this mean that the old activity is locked until this new one terminates?