I'm making a game with OpenGL Es 1.1 and i want to implement back button or menu button functionality to my game.(I mean hardware buttons).I have some subClasses so what i have to do when i want to handle hardware button press from subClasses?
You need to implement an onKeyDown listener and check to see what key is pressed.
Sample:
#Override
public boolean onKeyDown(int keycode, KeyEvent e) {
switch(keycode) {
case KeyEvent.KEYCODE_MENU:
handleMenuButton();
return true;
case KeyEvent.KEYCODE_BACK:
handleBackButton();
return true;
}
return super.onKeyDown(keycode, e);
}
Also note that for the back and menu buttons to fire reliably, you need to set setFocusableInTouchMode to true. See the devguide here (scroll down to "Touch Mode").
Related
I was wondering how does the home button or volume up/down button works in Android? Does pressing this button generates a hardware interrupt?
I would like to execute a piece of code with higher privilege (in kernel) by pressing this home/volume key. Is it possible? Any pointers?
if pressing these button generates a hardware interrupt, I think I have to modify the interrupt handler to execute the code I want to execute. Is this correct?
Thanks in advance!
#Override
public boolean onKeyDown(int keycode, KeyEvent e) {
switch(keycode) {
case KeyEvent.KEYCODE_MENU: // Menu button
doSomething();
return true;
case KeyEvent.KEYCODE_HOME: // Home button
doSomething();
return true;
case KeyEvent.KEYCODE_VOLUME_UP: // Volume Up key
doSomething();
return true;
case KeyEvent.KEYCODE_VOLUME_DOWN: // Volume Down key
doSomething();
return true;
}
return super.onKeyDown(keycode, e);
}
You can find more keys here.
I've got a Samsung tablet SM-T560 on which when pressing the touch 'menu' key (next to the hardware 'home' button) opens the system menu for 'Active apps' where you can close or navigate to a previously opened app.
How can i override this functionality?I want to disable showing active apps upon this menu button click.
you need to override the menu button using the onKeyDown(int, KeyEvent) method in your activity. The following code snippet should be a good start for you:
#Override
public boolean onKeyDown(int keycode, KeyEvent event) {
switch(keycode) {
case KeyEvent.KEYCODE_MENU:
//Your functionality here
return true;
}
return super.onKeyDown(keycode, event);
}
I use modal alert dialogs by calling setCancelable(false); By doing this the BACK hardware button is disabled. But unfortunately this is also true for the MENU hardware button. So the user does not have access to the option menu. I am using a Samsung Galaxy Tab3 with Android 4.4.2
How can I change this? Alternatively: Is there a possibility to catch the BACK button pressed event in a DialogFragment?
Something like this might do the trick :
#Override
public boolean onKeyDown(int keycode, KeyEvent e) {
switch(keycode) {
case KeyEvent.KEYCODE_MENU:
doSomething();
return true;
}
return super.onKeyDown(keycode, e);
}
(See more here : Android: How to add listener to hardware menu button?)
How I can change working of home button in android? I want to when I click on home button I do some actions and after that application should go to background. How I can do that.
Write your own home screen. When the user presses HOME, they will get a choice of running your app or the built-in home screen. They can elect to choose one just this one time, or set either app as being their default from now on. Many will wonder why on Earth you decided to decided to implement a home screen.
Most developers care about any case where their activity moves to the background, in which case you can either use a lifecycle method (e.g., onPause(), onStop()) or try onUserLeaveHint().
I do it this way:
/* Handles item selections */
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
//You can do whatever you want here
Intent homeInt = new Intent(this, SomeActivity.class);
startActivity(homeInt);
return true;
}
return false;
}
Have you tried overriding onKeyDown()
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_HOME) {
// ENTER CODE HERE
return true;
}
return super.onKeyDown(keyCode, event);
}
Right now when you hold down the menu button on my android device it pulls up a soft keyboard.Is there a way to override this? I would rather choose what happens on a long touch of this button.
When using onKeyLongPress it only detects when the "Back" button is held down. How can I make this work for the menu button?
For this, you can use the onKeyLongPress()-method, offered by the KeyEvent.Callback-class (can be used in Activity's too, since they are a subclass of the KeyEvent.Callback-class).
There is also a little trick to make this work: You'll have to tell Android to track a long-press click on the "Menu"-button as the onKeyLongPress()-method will not be triggered otherwise. This is done in the normal onKeyDown()-method.
So your code might look like this:
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_MENU) {
// this tells the framework to start tracking for
// a long press and eventual key up. it will only
// do so if this is the first down (not a repeat).
event.startTracking();
return true;
}
return super.onKeyDown(keyCode, event);
}
#Override
public boolean onKeyLongPress(int keyCode, KeyEvent event){
if (keyCode == KeyEvent.KEYCODE_MENU){
// Do what you want...
Toast.makeText(this, "I'm down!", Toast.LENGTH_SHORT).show();
return true;
}
return super.onKeyLongPress(keyCode,event);
}
A great article with further informations can be found on the Android Developer Blog.