Converting a character into keycode

Question

Converting a character into keycode

I have a character and I want to convert it into KeyEvent KeyCode constraints http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_0

Like if I have a character '0' I wan to convert into

Key code constant: '0' key.

Constant Value: 7 (0x00000007)

as specified in the KeyEvent page. What can be a best method for doing this? Is there any predefined function to do it?

android

asked on Stack Overflow Sep 6, 2013 by

dead programmer

4 Answers

Here is a solution I use to put chars in a webview:

char[] szRes = szStringText.toCharArray(); // Convert String to Char array

KeyCharacterMap CharMap;
if(Build.VERSION.SDK_INT >= 11) // My soft runs until API 5
    CharMap = KeyCharacterMap.load(KeyCharacterMap.VIRTUAL_KEYBOARD);
else
    CharMap = KeyCharacterMap.load(KeyCharacterMap.ALPHA);

KeyEvent[] events = CharMap.getEvents(szRes);

for(int i=0; i<events.length; i++)
    MainWebView.dispatchKeyEvent(events[i]); // MainWebView is webview

answered on Stack Overflow Jul 25, 2015 by

Philippe Mignard

I'm still new to Java/Android, so my answer may not work out of the box, but you may still get the idea.

import android.view.KeyCharacterMap;
import android.view.KeyEvent;    
...
public class Sample {
    ...
    public boolean convertStringToKeyCode(String text) {

        KeyCharacterMap mKeyCharacterMap = 
            KeyCharacterMap.load(KeyCharacterMap.VIRTUAL_KEYBOARD);

        KeyEvent[] events = mKeyCharacterMap.getEvents(text.toCharArray());

        for (KeyEvent event2 : events) {
            // We get key events for both UP and DOWN actions,
            // so we may just need one.
            if (event2.getAction() == 0) {
                int keycode = event2.getKeyCode();
                // Do some work
            }
        }
}

I got the idea when I was reading the code of sendText method in uiautomator framework source code:

answered on Stack Overflow Oct 21, 2014 by

Hieu

Very rude solution but works for most characters.

Remember to do an uppercase if your text contains lowercase letters, you can add META_SHIFT_ON in that case if you then send a KeyEvent

    for (int i = 0; i < text.length(); i++) {
        final char ch = text.charAt(i);
        try {
            dispatch(KeyEvent.class.getField("KEYCODE_" + ch).getInt(null));
        } catch (Exception e) {
            Log.e(_TAG, "Unknown keycode for " + ch);
        }
    }

answered on Stack Overflow May 21, 2015 by

Gianluca P.

No, you cannot read a character "0" from the input and use a magical function to transform that to KeyEvent.KEYCODE_0 ... If you do, you will have to write a parser that switches on the read letter and return these values yourself.

For all I know, before reading the character you should've captured the thing in the onKey(). Depending on the number of keys you need to handle this way, a virtual android keyboard might be your only option, if this boilerplate code doesn't do the trick

switch(keyPress)
{
  case '0': return KeyEvent.KEYCODE_0;
  case '1': return ...
  //...
  case 'Z': return KeyEvent.KEYCODE_Z;
}

answered on Stack Overflow Sep 6, 2013 by

Shark

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