Activity window on standard call screen - to Enable buttons

I would like to add a small window (Popup) on call screen activity. Google voice and worldcallplaceandtime are both adding the same window during a call.

The problem is that when I open a new activity on the top part of the screen, the rest of the buttons are disabled (End call, Mute etc). The only opti开发者_StackOverflow中文版on to click the end call button is only when I close the new activity that was added.

Can anyone please tell me how can I add a small window one the screen and still be able to use the call standard buttons?

This is the code I used to add an overlay button on the call screen without disabling the buttons. I hope it helps..

    public void addInvitePopup(final String number){
    //check if pref is ok with invite in call
    if(!Preferences.getInstance(getApplicationContext()).getInviteInCall()){return ; }
    // sets the WindowManager
    wm = (WindowManager) getApplicationContext().getSystemService(Context.WINDOW_SERVICE);

    WindowManager.LayoutParams params = new WindowManager.LayoutParams(
            LayoutParams.WRAP_CONTENT,
            LayoutParams.WRAP_CONTENT,
            WindowManager.LayoutParams.TYPE_SYSTEM_ALERT | 
            WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY,
            WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL |
            WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE,
            PixelFormat.TRANSLUCENT);
    params.x = 250;
    params.height = LayoutParams.WRAP_CONTENT;
    params.width = LayoutParams.WRAP_CONTENT;
    params.format = PixelFormat.TRANSLUCENT;


    params.gravity = Gravity.TOP;
    params.setTitle("Testing");

    ly = new LinearLayout(getApplicationContext());
    ly.setOrientation(LinearLayout.VERTICAL);

    Button inviteButton = new Button(getApplicationContext());
    inviteButton.setClickable(true);
    inviteButton.setBackgroundDrawable(getResources().getDrawable(R.drawable.invite_incall_off));
    inviteButton.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            Toast.makeText(v.getContext(), "Inviting by free SMS..", Toast.LENGTH_LONG).show();
            v.setBackgroundDrawable(getResources().getDrawable(R.drawable.invite_incall_on));
            v.setClickable(false);
            sendMessage(v, number);

            //Track this event:
            MixPanelTracking.setPropKeyValue(getApplicationContext(), null, null, "Add friend - During Call");
        }
    });

    //closeInviteButton. ///////////////////////
    closeInviteButton = new Button(getApplicationContext());
    closeInviteButton.setClickable(true);
    //closeInviteButton.setGravity(Button.);
    closeInviteButton.setBackgroundDrawable(getResources().getDrawable(R.drawable.close_invitebutton_off));
    closeInviteButton.setWidth(30);
    closeInviteButton.setHeight(30);
//  closeInviteButton.setLayoutParams(WindowManager.LayoutParams.WRAP_CONTENT,
//          WindowManager.LayoutParams.WRAP_CONTENT);

    closeInviteButton.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            removeInvitePopup();
            //Add to Preferences:
            //Preferences.getInstance(v.getContext()).setInviteInCall(false);
            //Track this event:

        }
    });
    ////////////////////////////////////////////
    ly.addView(inviteButton);

    wm.addView(ly, params);
    wm.addView(closeInviteButton, params);
    Log.i("TTT", "after add view");
}
public void removeInvitePopup(){
    if(ly != null){
        wm.removeView(ly);
        wm.removeView(closeInviteButton);
        ly =  null;
        closeInviteButton = null;
    }
}

If I use that i receive an exception when using removeInvitePopup() on IDLE state. Close invite button does not dissapear when you miss the call