Want the custom keyboard ONLY for MY APP and restore the previous one when the app loses focus

I made this "regular keyboard" by following the wonderful diagram in this link AND NOT USING ECLIPSE. I used Android Studio ( AS ) 1.1.0.

Screenshot from my device:

The only problem is that the procedure requires a setting change for Language and Input

AND ALSO replaces the FOR ALL APPS keyboard . I do not want it. I just want MY app to change the keyboard for ITSELF and then switch back to the previous keyboard as soon as my app disconnects from the screen, otherwise I'm going to be a huge pain in the users' butts. Instead, I can simply add buttons to perform keystrokes, which I hoped would be triggered by a custom keyboard. (It's not terrible, the user just needs to remove the notification bar and select an input method, but still too intrusive for most users.)

Here's the structure:

The keyboard has been changed to qwerty.xml

by doing a lot of the following:

<Keyboard xmlns:android="http://schemas.android.com/apk/res/android"
          android:keyWidth="10%p"
          android:horizontalGap="0px"
          android:verticalGap="0px"
          android:keyHeight="60dp"
    >
    <Row>
        <Key android:codes="49" android:keyLabel="1" android:keyEdgeFlags="left"/>
        <Key android:codes="50" android:keyLabel="2"/>
        <Key android:codes="51" android:keyLabel="3"/>
        <Key android:codes="52" android:keyLabel="4"/>
        <Key android:codes="53" android:keyLabel="5"/>
        <Key android:codes="54" android:keyLabel="6"/>
        <Key android:codes="55" android:keyLabel="7"/>
        <Key android:codes="56" android:keyLabel="8"/>
        <Key android:codes="57" android:keyLabel="9"/>
        <Key android:codes="48" android:keyLabel="0" android:keyEdgeFlags="right"/>
    </Row>
...

      

        
        
        
      

    

Here method.xml

:

<?xml version="1.0" encoding="utf-8"?>
<input-method xmlns:android="http://schemas.android.com/apk/res/android">
    <subtype
        android:label=              "@string/subtype_en_US"
        android:imeSubtypeLocale=   "en_US"
        android:imeSubtypeMode=     "keyboard" 
    />
</input-method>

      

        
        
        
      

    

Here AndroidManifest.xml

:

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.dslomer64.simplekeyboard">

    <application

                android:allowBackup="true"
                android:label="@string/app_name"
                android:icon="@mipmap/ic_launcher"
                android:theme="@style/AppTheme">

                <service android:name=".SimpleIME"
                     android:label="@string/simple_ime"
                     android:permission="android.permission.BIND_INPUT_METHOD"
                >
                <meta-data android:name="android.view.im" android:resource="@xml/method"/>
                <intent-filter>
                    <action android:name="android.view.InputMethod" />
                </intent-filter>
        </service>

    </application>

</manifest>

      

        
        
        
      

    

service

added to the manifest is what gets to the soft keyboard via code in SimpleIME.java

(empty overrides omitted):

import android.inputmethodservice.InputMethodService;
import android.inputmethodservice.Keyboard;
import android.inputmethodservice.KeyboardView;
import android.media.AudioManager;
import android.view.KeyEvent;
import android.view.View;
import android.view.inputmethod.InputConnection;

public class SimpleIME extends InputMethodService
    implements KeyboardView.OnKeyboardActionListener
{

  private KeyboardView kv;
  private Keyboard keyboard;

  private boolean caps = false;

  @Override
  public View onCreateInputView() {
    kv = (KeyboardView)getLayoutInflater().inflate(R.layout.keyboard, null);
    keyboard = new Keyboard(this, R.xml.qwerty);
    kv.setKeyboard(keyboard);
    kv.setOnKeyboardActionListener(this);
    return kv;
  }
  private void playClick(int keyCode){
    AudioManager am = (AudioManager)getSystemService(AUDIO_SERVICE);
    switch(keyCode){
      case 32:
        am.playSoundEffect(AudioManager.FX_KEYPRESS_SPACEBAR);
        break;
      case Keyboard.KEYCODE_DONE:
      case 10:
        am.playSoundEffect(AudioManager.FX_KEYPRESS_RETURN);
        break;
      case Keyboard.KEYCODE_DELETE:
        am.playSoundEffect(AudioManager.FX_KEYPRESS_DELETE);
        break;
      default: am.playSoundEffect(AudioManager.FX_KEYPRESS_STANDARD);
    }
  }
  @Override
  public void onKey(int primaryCode, int[] keyCodes) {
    InputConnection ic = getCurrentInputConnection();
    playClick(primaryCode);
    switch(primaryCode){
      case Keyboard.KEYCODE_DELETE :
        ic.deleteSurroundingText(1, 0);
        break;
      case Keyboard.KEYCODE_SHIFT:
        caps = !caps;
        keyboard.setShifted(caps);
        kv.invalidateAllKeys();
        break;
      case Keyboard.KEYCODE_DONE:
        ic.sendKeyEvent(new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_ENTER));
        break;
      default:
        char code = (char)primaryCode;
        if(Character.isLetter(code) && caps){
          code = Character.toUpperCase(code);
        }
        ic.commitText(String.valueOf(code),1);
    }
  }
    ...
}

      

        
        
        
      

    

I wonder if anyone out there did what I needed: implement the JUST FOR ONE APP custom keyboard and restore the original after losing the screen focus.