How can I use the Android back button to move back within my app instead of closing my app?
My app has three activities, A, B and C. I am moving from A to B through an OK button, and I want to move b开发者_Python百科ack from B to A by using the default back button of Android devices. When I press the button, though, the entire app gets closed. How can I get around this problem?
I suspect you call finish()
in your OK button onclick listener. Don't do that. finish()
removes your activity from activity stack.
Read more here.
why start your activity for result ? when you press the backbutton, the result is set to RESULT_CANCELED form the B activity, so it crashes if you don't handle the resultcode...
you can handle the backpress like this
private static final int NONE = -1;
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
setResult(NONE, intent);
finish();
return super.onKeyDown(keyCode, event);
}
When you are Ok button r u starting an intent...like
Intent int=new intent(context,B.class); startActivity(int);
then if you are not handling backbutton.
If use default back button...it will goes back to A.
Hope it helps...
In my onClick method (in Main Activity) I use the code:
Intent intent = new Intent(context, SecondActivity.class);
context.startActivityForResult(intent, SecondActivity.SECONDACTIVITY_REQUEST);
In the manifest I've got:
<activity android:name=".SecondActivity" android:screenOrientation="landscape" android:launchMode="standard"></activity>
This works for me without any other settings that I can see. What events are you responding to?
Note that you can also go back an activity, in code like this:
super.setResult(Activity.RESULT_OK);
super.finish();
Edit... Make sure you're not swallowing the event in the Main Activitys onKeyDown event.
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
//your code here
//if (keyCode ==
//...
//else
return super.onKeyDown(keyCode, event);
}
精彩评论