There are several ways to update your UI and modify a View
such as a TextView
from outside of the UI Thread. A Handler
is just one method.
Here is an example that allows a single Handler
respond to various types of requests.
At the class level define a simple Handler
:
private final static int DO_UPDATE_TEXT = 0;
private final static int DO_THAT = 1;
private final Handler myHandler = new Handler() {
public void handleMessage(Message msg) {
final int what = msg.what;
switch(what) {
case DO_UPDATE_TEXT: doUpdate(); break;
case DO_THAT: doThat(); break;
}
}
};
Update the UI in one of your functions, which is now on the UI Thread:
private void doUpdate() {
myTextView.setText("I've been updated.");
}
From within your asynchronous task, send a message to the Handler
. There are several ways to do it. This may be the simplest:
myHandler.sendEmptyMessage(DO_UPDATE_TEXT);
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