Using toast inside timertask

Question

Found someone has similar issue online here.

This doesn\'t work:

Timer t = new Timer(false);
t.schedule(new TimerTask() {
@Override
public void run()         


        

Answer 1

Everytime you start an application, it starts on the UI Thread (also called the Main Thread).

Whenever you create a new Thread, or Timer, or AsyncTask, by definition, they're creating new Threads. Threads that aren't the main thread simply don't have permission to modify the UI.

Answer 2

try this

Timer t = new Timer(false);
t.schedule(new TimerTask() {
@Override
public void run() {
       runOnUiThread(new Runnable() {
            public void run() {
                Toast.makeText(getApplicationContext(), "msg", Toast.LENGTH_LONG).show();
            }
        });

    }
}, 5000);

Answer 3

Toast use on UIThread. You can by Handler or runOnUiThread

Answer 4

Using Timer starts a new thread, I suppose that thread does not have access to getApplicationContext. The proper way to do it is to use Handler and call the postDelayed method of the Handler - which does not start a new thread.

Read about this: http://developer.android.com/resources/articles/timed-ui-updates.html

The link you posted has a working example, which is the proper way to do it:

final Context ctx = this;
Handler mHandler = new Handler();

Runnable
makeToast = new Runnable() {
    public void run() {
        Toast.makeText(ctx, "msg", Toast.LENGTH_LONG).show();
    }
};
mHandler.postDelayed(makeToast, 1000);