Android runOnUiThread explanation

Question

I am trying to display a progress dialog during the onCreate() method of one of my activities, have the work done to populate the screen done in a thread, and then dismiss the progress dialog.

Here is my onCreateMethod()

dialog = new ProgressDialog(HeadlineBoard.this);         dialog.setMessage("Populating Headlines.....");         dialog.show();         populateTable(); 

The populateTable method contains my thread and the code to dismiss the dialog, but for some reason. The activity comes up blank for about 10 secs(doing the populateTable() work), and then I see the screen. I never see the dialog displayed, any ideas?

Here is the populateTable() code:

//Adds a row to the table for each headline passed in private void populateTable() {     new Thread() {         @Override         public void run() {             //If there are stories, add them to the table             for (Parcelable currentHeadline : allHeadlines) {                 addHeadlineToTable(currentHeadline);             }                try {                      // code runs in a thread                      runOnUiThread(new Runnable() {                             @Override                             public void run() {                                 dialog.dismiss();                             }                      });                } catch (final Exception ex) {                    Log.i("---","Exception in thread");                }         }  }.start();  } 

Answer 1

If you already have the data "for (Parcelable currentHeadline : allHeadlines)," then why are you doing that in a separate thread?

You should poll the data in a separate thread, and when it's finished gathering it, then call your populateTables method on the UI thread:

private void populateTable() {     runOnUiThread(new Runnable(){         public void run() {             //If there are stories, add them to the table             for (Parcelable currentHeadline : allHeadlines) {                 addHeadlineToTable(currentHeadline);             }             try {                 dialog.dismiss();             } catch (final Exception ex) {                 Log.i("---","Exception in thread");             }         }     }); }