Develop Reference

Getting the pressed character without using edidtext

I want to get a pressed character in the code without using edittext.
Simply a black screen appear if someone presses "a" or "b" etc.. I want to get this value in my code.
I have done it using editext and textwatcher but the requirement is we don't need to use them now.
Can we make character(alphabet) moving from top to bottom randomly
I have followed some links which have used marquee but it does not work.

In your Activity override the method
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_A) {
//Here your black screen if you press A
return true;
}
return super.onKeyDown(keyCode, event);
}
Check this KeyEvent ;

how to handle numeric keys from the phone keypad

In following keypad:
we can select value by pressing buttons (e.g View button1.setOnClickListener(..)), all i want to know is how can i handle keys(keys 0 to 9, enter_key, clear_key) from the phone keypad (e.g. when running on device other then tablet).
Please give a quick refference. any online tutorial will be highly helpfull.
regards,

you can go for onKeyDown which takes keycode and KeyEvent as arguments and KeyEvent class contains all the numeric codes:
public boolean onKeyDown(int keyCode, KeyEvent event) {
if(keyCode==KeyEvent.KEYCODE_0){
//do some stuffs
}else if(keyCode==KeyEvent.KEYCODE_1) {
// do some stuffs
}
return super.onKeyDown(keyCode, event);
}
Like this you can handle numeric key press/.Hope it wil help you. :)

How can I create a long touch event on the physical menu button?

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.

Android: menu and back button stop working

For my android app I have multiple edittexts on the main screen. If i have the first edittext in focus the menu/back buttons operate fine, if i have any of the other edittexts in focus than neither of them work at all. I'm not doing anything special regarding the menu/back buttons relative to that edittext, i'm not sure what the cause is? Has anyone run into a similar issue and/or know of the cause/solution?
Thanks!

I was have the same problem and I found solution for I was have OnKeyListener that return true; when I change it to return false; the problem was fixed
my_editText.setOnKeyListener(new OnKeyListener() {
#Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
// you can use the next line to ensure back button & menu button will return false
if (event.getKeyCode() == KeyEvent.KEYCODE_BACK || event.getKeyCode() == KeyEvent.KEYCODE_MENU) return false;
// any other key you don't want to call other listener for it
if (event.getKeyCode() == KeyEvent.KEYCODE_ENTER&& event.getAction() == KeyEvent.ACTION_UP) {
return true;
}
return false;
}
});
OnKeyListener.onKey(android.view.View, int, android.view.KeyEvent)

easy fix for me, I had removed the only keyboard app.
just install a keyboard app and the buttons worked again

Android: onKeyListener simulating two instances of a pressed key [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
public boolean onKey() called twice?
Display.setOnKeyListener(new OnKeyListener() {
public boolean onKey(View v, int keyCode, KeyEvent event) {
switch (keyCode) {
case KeyEvent.KEYCODE_ENTER:
solveExpression();
return true;
}
return false;
}
});
I'm trying to solve the expression contained within the Display(EditText), by pressing the enter button on the keyboard, yet it always interprets it as though I pressed the button twice. Does anyone know why this happens?

Try...
Display.setOnKeyListener(new OnKeyListener() {
public boolean onKey(View v, int keyCode, KeyEvent event) {
switch (keyCode) {
case KeyEvent.KEYCODE_ENTER:
// Check for ACTION_DOWN only...
if (KeyEvent.ACTION_DOWN == event.getAction()) {
solveExpression();
return true;
}
}
}
});
The 'action' can be ACTION_DOWN, ACTION_UP or ACTION_MULTIPLE (the last being for when a key is pressed and held). onKey() will be called for any/all of those actions.
As the other answer mentions, it's triggering twice because it's once for down and once for up.

if (event.getAction()!=KeyEvent.ACTION_DOWN) // we catch only key down events
return true;
Thus you stop listening other keyevents as onClick.
If you want nobody else further in chain to get the event for another piece of work, you should set
return false;

not an android guy either but the fact that it registers twice makes me think that OnKey encompasses a onKeyDown and onKeyUp. Would listening to onKeyUp work for you as well?