====== Android buttons and touch events ======
This tutorial shows how to add a button to your application and handle touch events.
===== Add button to your layout =====
  - Go to ''app/res/layout/content_robot_layout.xml''
  - Drag and drp button from the menu on the left to the visualization of a mobile phone screen.
  - Change the name and the ID of the button to something more unique, let's say ID: ''goForward'' and Text: ''FORWARD''.
  - Click on a Text representation of the layout and see how it is represented in XML (do not change anything, unless you know what you're doing)
{{ :did:roboclub:android_tutorials:add-button.png|}}

===== Add touch listener =====
  - Go to ''app/java/geist.re.mindroid/RobotControl''
  - Find ''onCreate'' method (it should be around line 123
  - Insert the following code to add touch events handlers for your button (note, that the id of the button should be changed to whatever you name it): <code java>
//Change the id here
Button goForward = (Button) findViewById(R.id.button);
goForward.setOnTouchListener(new View.OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        if(robot == null || robot.getConnectionState() != RobotService.CONN_STATE_CONNECTED){
            return false;
        }
        switch(event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                //Run motors
                return true; // if you want to handle the touch event
            case MotionEvent.ACTION_UP:
                //Stop motors
                return true; // if you want to handle the touch event
        }
        return false;
    }
});</code>

{{ :did:roboclub:android_tutorials:add-touch-listeners.png|}}
===== Add onClick method =====
In case you just want to handle basic //tap// event, you can do it by adding ''onClick'' method to your button.
Note, that releasing the button will not be handled.

  - In text representation of the layout add ''onClick'' field to your button definition and assign it a namne of a function you want to call in case of //tap// event.
  - In ''app/java/geist.re/mindroid/RobotControl'' add the function of the same name as in the previoud step, that takes ''View v'' as a parameter:<code java>public void goForward(View w){
//Do some col stuff in here
}
</code>
  - That's it. Every time the user clicks the button, the function you've created will be called.

{{ :did:roboclub:android_tutorials:add-method.png|}}