How to add a touch listener to a surface view?
<p>I am new to Android, so please excuse if it is asked before!</p>

<p>I am playing with some camera code (found online) and I want to show/hide some buttons on screen. When the user touches the screen, I want it to capture the image. </p>

<p>My setup:</p>

<p>1.
Main Activity:</p>

<pre><code>public class CameraDemo extends Activity {
/** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_inuse);

        preview = new Preview(this);

        ((FrameLayout) findViewById(R.id.preview)).addView(preview);

... ...  
// rest of the code that captures the image when a button is pressed.
// the button is defined in main.xml with button id ButtonClicked
}
</code></pre>

<p>2.
The preview class looks like this:</p>

<pre><code>class Preview extends SurfaceView implements SurfaceHolder.Callback {

    SurfaceHolder mHolder;
    public Camera camera;

    Preview(Context context) {
        super(context);

        // Install a SurfaceHolder.Callback so we get notified when the
        // underlying surface is created and destroyed.
        mHolder = getHolder();
        mHolder.addCallback(this);
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
</code></pre>

<p>My question is,</p>

<ol>
<li><p>How can I add touch functionality so that the user can touch the preview (say for a second, or just touch quickly) and something happens ? (Say image is saved)</p></li>
<li><p>And a button will appear on the surface say a "Next" button, for example?</p></li>
</ol>
