How to add textview with one touch?

Question

Java

Please tell me...
You need to open the alertdialog with edittext with one touch to the screen. After send the text from the edittext to the TextView at the touch location.

private void onDrawTexts(Canvas canvas) {
        float dx = Math.abs(mx - mStartX);
        float dy = Math.abs(my - mStartY);
        if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
            
        }
    }
private void onTouchEventTexts(MotionEvent event) {
 
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                isDrawing = true;
                mStartX = mx;
                mStartY = my;   
                invalidate();
                break;
            case MotionEvent.ACTION_MOVE:
                invalidate();
                break;
            case MotionEvent.ACTION_UP:
                isDrawing = false;
                String txt = "0000" ;
                mCanvas.drawText (txt, mx,my,mPaintText);
                invalidate();
                break;
        }
    }