AsyncTask not generic?

When I try to compile to following code, I get two errors:

Description Resource Path Location Type Syntax error on token "void", invalid Expression AsyncTask.java /AsyncTask Project/src/org/me/asynctask line 19 Java Problem

Description Resource Path Location Type The type AsyncTask is not generic; it cannot be parameterized with arguments AsyncTask.java /AsyncTask Project/src/org/me/asynctask line 25 Java Problem

package org.me.asynctask;

import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.widget.TextView; import android.widget.Toast; import android.os.*; public class AsyncTask extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main);

    TextView mytextview = new TextView(this);
    TextView secondtextview = new TextView(this);

    new MyAsyncClass().execute(mytextview, void, secondtextview);

}



private class MyAsyncClass extends AsyncTask<TextView, Void, Void> {
 protected TextView doInBackground(TextView tv)
 {
  tv.setText("Your AsyncTask was successful!");
  return tv;
 }


 protected void onPostExecute(TextView Result)
 {
  Context context = context.getApplicationContext();
        Toast mytoast = Toast.makeText(context, "AsyncTask processing complete", Toast.LENGTH_LONG);
        mytoast.show();
 }

}

Obviously AsyncTask IS a generic (http://developer.android.com/reference/android/os/AsyncTask.html#execute(Params...) so why do i get those errors?

---

There are several problems, two of which are:

You defined a class AsyncTask , which hides/collides with android.os.AsyncTask . Maybe you intended to call it AsyncTaskDemo.java or AsyncTaskActivity.java or something.

You're trying to change the UI from the background thread by calling tv.setText inside of doInBackground . That defeats the purpose of AsyncTask . Code in doInBackground shouldn't be touching the main (or 'UI') thread. For mid-task updates inside of doInBackground , use AsyncTask.publishProgress .

---

You are overriding the AsyncTask methods with the wrong types. It is defined as:

AsyncTask<Params, Progress, Result>

and the doInBackground method is defined as protected abstract Result doInBackground (Params... params)

so according to your definition, you should have protected Void doInBackround(TextView... params);

onPostExecute is also incorrectly defined.

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