Overriding the functionality of Home Button

Question

In android I have been able to override the functionality of back button very easily but for my app I need to override the home button. For example the user is in Activity A, when he presses the home button, activity B is launched. I have tried to do the following but it failed.

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {

    if(keyCode == KeyEvent.KEYCODE_HOME)
    {
        startActivity(new Intent(this, ActivityB.class));

        return true;
    }
    return super.onKeyDown(keyCode, event);
}

I am sure it can be done because in Nova Launcher when the user is on home screen and he presses the home button, the launcher offers the user a list of home screens to jump to. I need same kind of functionality. How can this be achieved.

Regards

activity a and b are of the same application? you cannot override home button functionality — Raghunandan, Aug 22 '13 at 12:41
Would the downvoter care for stating the reason for downvote? I never said disabling the home button because it doesn't work for android 4.0+ . — Umer Farooq, Aug 22 '13 at 12:55

JiTHiN · Accepted Answer · 2013-08-22T13:01:58.230

5

Try this:

@Override
    protected void onUserLeaveHint() {
        if (!navigating) {
            Intent intent2 = new Intent();
            intent2.setClass(ActivityA.this, ActivityB.class);
            intent2.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
            forceHome(this, intent2);
        }
        super.onUserLeaveHint();
    }

public static void forceHome(Context paramContext, Intent paramIntent) {

        if (paramIntent != null) {
            ((AlarmManager) paramContext.getSystemService(ALARM)).set(1,
                    System.currentTimeMillis(),
                    PendingIntent.getActivity(paramContext, 0, paramIntent, 0));
        }

    }

As a security feature of android, the activity only launches after 5 seconds. If you want to launch it immediately. use your own Home Launcher.

edited Aug 22 '13 at 13:01

answered Aug 22 '13 at 12:51

JiTHiN

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it doesn't launch even after 5 secs – Umer Farooq Aug 22 '13 at 12:58
what is the version of your android emulator? – Umer Farooq Aug 22 '13 at 13:02
With this method? No. The only other option is to create your own Home Launcher. – JiTHiN Aug 22 '13 at 13:09
you mean full fledge launcher? – Umer Farooq Aug 22 '13 at 13:13
let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/36012/discussion-between-rihan-jithin-and-umer-farooq) – JiTHiN Aug 22 '13 at 13:13
can you come to chatroom for a moment? – Umer Farooq Aug 22 '13 at 14:02
There are couple of issues with my home screen app. First is the apps started from my home screen don't return to my home screen, rather they go to android launcher home screen even though I have set my home screen as default. The other issue is I am enabling & disabling of my activities to give illusion to the system that user has changed the default home screen but the promt for selecting defualt screen doesn't appear. How can I solve these problems? – Umer Farooq Aug 23 '13 at 06:10

Raghunandan · Answer 2 · 2013-08-22T13:03:34.167

3

No you can't override the functionality of HomeButton. Its for security reasons so that malicious apps does not take control of your home button.

If you want to handle home button inplement home screen.

I am not sure if the below is helpfull.

You can Override onUserLeaveHint

protected void onUserLeaveHint () if you want to

Added in API level 3Called as part of the activity lifecycle when an activity is about to go into the background as the result of user choice. For example, when the user presses the Home key, onUserLeaveHint() will be called, but when an incoming phone call causes the in-call Activity to be automatically brought to the foreground, onUserLeaveHint() will not be called on the activity being interrupted. In cases when it is invoked, this method is called right before the activity's onPause() callback. This callback and onUserInteraction() are intended to help activities manage status bar notifications intelligently; specifically, for helping activities determine the proper time to cancel a notfication.

edited Aug 22 '13 at 13:03

answered Aug 22 '13 at 12:43

Raghunandan

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I have overriden this method and trying to start the new activity in it, but it doesn't seem to work. What should I do to achieve my goal? – Umer Farooq Aug 22 '13 at 12:46
@UmerFarooq the answer is a simple no you can't override home button functionality. – Raghunandan Aug 22 '13 at 12:48
@Raghunandan: Then, how is the child lock feature of MX Player working? – JiTHiN Aug 22 '13 at 12:55
@rIHaNJiTHiN i don't know gotta ask the developer – Raghunandan Aug 22 '13 at 12:57
@Raghunandan: It was just FYI that home button can be overridden. – JiTHiN Aug 22 '13 at 12:58
@rIHaNJiTHiN http://stackoverflow.com/questions/13139970/override-home-key-in-android-ics. not possible you will to find a work around and even if possible using workaround i would not recommend it – Raghunandan Aug 22 '13 at 12:59
@Raghunandan My question is the same as changing the functionality of home button like MX player or Nova launcher does. I am not asking for disabling the home button. But some idiot down voted the question! – Umer Farooq Aug 22 '13 at 12:59
@UmerFarooq you can ask that idiot why he donwvoted i din't. also i don't know about MX player may be ask the developer – Raghunandan Aug 22 '13 at 13:01
yep I agree with you bro. I think I should ask the player dev :) – Umer Farooq Aug 22 '13 at 13:03
@Raghunandan how can I implement a home screen? – Umer Farooq Aug 22 '13 at 13:10

score 2 · Answer 3 · answered Aug 22 '13 at 12:44

2

Try to override this method and write your code.

 @Override
 protected void onStop() 
 {
     super.onStop();
     startActivity(new Intent(this, ActivityB.class));
 }

answered Aug 22 '13 at 12:44

Mehul Ranpara

4,245
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Overriding the functionality of Home Button

3 Answers3

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