Add Broadcast to Custom Button in Android and Assign Value to Current Focused Input Box via Broadcast

1. Add broadcast for custom button

Modify the interceptKeyBeforeDispatching method in PhoneWindowManager.java

/frameworks/base/policy/src/com/android/internal/policy/impl/PhoneWindowManager.java

@Override
  public long interceptKeyBeforeDispatching(WindowState win, KeyEvent event, int policyFlags) {
    final boolean keyguardOn = keyguardOn();
    final int keyCode = event.getKeyCode();
    final int repeatCount = event.getRepeatCount();
    final int metaState = event.getMetaState();
    final int flags = event.getFlags();
    final boolean down = event.getAction() == KeyEvent.ACTION_DOWN;
    final boolean canceled = event.isCanceled();
    final boolean longPress = (flags & KeyEvent.FLAG_LONG_PRESS) != 0;
    final boolean virtualKey = event.getDeviceId() == KeyCharacterMap.VIRTUAL_KEYBOARD;
    final String isCitKeyTest=SystemProperties.get("persist.sys.startCitKeyTest");
    //Add Custom Key Broadcast----Start
    switch (keyCode)
      {
        case 135:
        case 136:
        case 137:
        case 139:
        {
          if (repeatCount == 0) {
            Intent myKeyIntent = new Intent();
            if(down)
            {
              myKeyIntent.setAction("com.rscja.android.KEY_DOWN");
            }
            else
            {
              myKeyIntent.setAction("com.rscja.android.KEY_UP");
            }
            myKeyIntent.putExtra("keycode", keyCode);
            mContext.sendBroadcastAsUser(myKeyIntent, UserHandle.ALL); 
          }
        }
          break;
      }
      //Add Custom Key Broadcast----End
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}

Part Two: Assigning Values to the Current Focused Input Box via Broadcast

Modify the onCreate() method in InputMethodService.java

/frameworks/base/core/java/android/inputmethodservice/InputMethodService.java

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