Progress Dialog and Threads
From John Freier
These are nice to use when you need to create a "waiting..." dialog. For example when you make a call to the internet, you would use one, so the user does not have to wait.
One of the issues I ran across was accessing class variables. After a lot of research, I figured out, that you can access variable through a class Handler. You pass variable to the handler through the messages.
Example:
Create a private class variable.
private ProgressDialog dialog;
This is the handler so that you can access class variables. example: text boxes, images...
private Handler handlerRefresh = new Handler() { @Override public void handleMessage(Message msg) { Bundle resBundle = (Bundle) msg.obj; String name= resBundle.getString("key"); } }
This is the thread creation, it will show the dialog and process in the background.
dialog = ProgressDialog.show(CurrentActivity.this, "","Please wait...", true); new Thread(new Runnable() { public void run() { // Threaded process... String name = "John"; Message myMessage=new Message(); Bundle resBundle = new Bundle(); resBundle.putString("key", name); myMessage.obj=resBundle; handlerRefresh.sendMessage(myMessage); dialog.dismiss(); } }).start();