How can I give an imageview click effect like a button on Android?

Question

I have imageview in my Android app that I am using like a button with the onClick event given, but as you might guess it is not giving imageview a clickable effect when clic

Answer 1

For defining the selector drawable choice

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_selected="true"   
        android:drawable="@drawable/img_down" />
    <item android:state_selected="false"   
        android:drawable="@drawable/img_up" />
</selector>

I have to use android:state_pressed instead of android:state_selected

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed ="true"   
        android:drawable="@drawable/img_down" />
    <item android:state_pressed ="false"   
        android:drawable="@drawable/img_up" />
</selector>

Answer 2

I have a more beauty solution if you use background images :)

public static void blackButton(View button){
    button.setOnTouchListener(new OnTouchListener() {

        public boolean onTouch(View v, MotionEvent event) {
            switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN: {
                    v.getBackground().setColorFilter(0xf0f47521,PorterDuff.Mode.SRC_ATOP);
                    v.invalidate();
                    break;
                }
                case MotionEvent.ACTION_UP: {
                    v.getBackground().clearColorFilter();
                    v.invalidate();
                    break;
                }
            }
            return false;
        }
    });
}

Answer 3

Here's my solution, which, using "nineOldAndroids" library, supports old APIs too:

rootView.setOnTouchListener(new OnTouchListener() {

    @Override
    public boolean onTouch(final View v, final MotionEvent event) {

        switch (event.getAction()) {

            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_CANCEL:
                v.setBackgroundResource(R.drawable.listview_normal);
                ViewHelper.setAlpha(imageView, 1);
                break;

            case MotionEvent.ACTION_DOWN:
                v.setBackgroundResource(0);
                v.setBackgroundColor(getResources().getColor(R.color.listview_pressed));
                ViewHelper.setAlpha(imageView, 0.75f);
                break;
        }
        return false;
    }
});

It assumes the rootView is the cell itself (the layout), and that it has a single imageView that you wish to be affected by the color that you wish to apply to the whole cell.

---

EDIT: if you wish, you can also extend ImageView to handle foreground, and set it to "?android:attr/selectableItemBackground". There is a library for this here and a tutorial on how to do it for any view you wish, here.

Answer 4

You can design different images for clicked/not clicked states and set them in the onTouchListener as follows

final ImageView v = (ImageView) findViewById(R.id.button0);
        v.setOnTouchListener(new OnTouchListener() {
            @Override
            public boolean onTouch(View arg0, MotionEvent arg1) {
                switch (arg1.getAction()) {
                case MotionEvent.ACTION_DOWN: {
                    v.setImageBitmap(res.getDrawable(R.drawable.img_down));
                    break;
                }
                case MotionEvent.ACTION_CANCEL:{
                    v.setImageBitmap(res.getDrawable(R.drawable.img_up));
                    break;
                }
                }
                return true;
            }
        });

The better choice is that you define a selector as follows

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_selected="true"   
        android:drawable="@drawable/img_down" />
    <item android:state_selected="false"   
        android:drawable="@drawable/img_up" />
</selector>

and select the image in the event:

v.setOnTouchListener(new OnTouchListener() {
            @Override
            public boolean onTouch(View arg0, MotionEvent arg1) {
                v.setSelected(arg1.getAction()==MotionEvent.ACTION_DOWN);
                return true;
            }
        });

Answer 5

This worked for me:

img.setOnTouchListener(new OnTouchListener(){

            @Override
            public boolean onTouch(View v, MotionEvent event) {
                switch (event.getAction())
                {
                    case MotionEvent.ACTION_DOWN:
                    {
                        ((ImageView)v).setImageAlpha(200);
                        break;
                    }
                    case MotionEvent.ACTION_MOVE:
                    {
                        // if inside bounds
                        if(event.getX() > 0 && event.getX() < v.getWidth() && event.getY() > 0 && event.getY() < v.getHeight())
                        {
                            ((ImageView)v).setImageAlpha(200);
                        }
                        else
                        {
                            ((ImageView)v).setImageAlpha(255);
                        }

                        break;
                    }
                    case MotionEvent.ACTION_UP:
                    {
                        ((ImageView)v).setImageAlpha(255);
                    }
                }
                return true;
            }

        });

@Edit: As Gunhan said there will be backward compatibility problem with setImageAlpha method. I used this method:

public static void setImageAlpha(ImageView img, int alpha)
    {
        if(Build.VERSION.SDK_INT > 15)
        {
            img.setImageAlpha(alpha);
        }
        else
        {
            img.setAlpha(alpha);
        }
    }

Answer 6

Thanks for the help on this thread. However, you missed one thing...you need to handle the ACTION_CANCEL as well. If you don't then you might not properly restore the alpha value of the ImageView in the event that a parent view in the view hierarchy intercepts a touch event (think a ScrollView wrapping you ImageView).

Here is a complete class that is based off the above class but takes care of the ACTION_CANCEL as well. It uses an ImageViewCompat helper class to abstract the differences in the pre-post JellyBean API.

public class ChangeAlphaOnPressedTouchListener implements OnTouchListener {

    private final float pressedAlpha;

    public ChangeAlphaOnPressedTouchListener(float pressedAlpha) {
        this.pressedAlpha = pressedAlpha;
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        ImageView iv = (ImageView) v;
        switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            ImageViewCompat.setAlpha(iv, pressedAlpha);
            break;

        case MotionEvent.ACTION_MOVE:
            if (isInsideViewBounds(v, event)) {
                ImageViewCompat.setAlpha(iv, pressedAlpha);
            } else {
                ImageViewCompat.setAlpha(iv, 1f);
            }
            break;
        case MotionEvent.ACTION_UP:
            ImageViewCompat.setAlpha(iv, 1f);
            break;
        case MotionEvent.ACTION_CANCEL:
            ImageViewCompat.setAlpha(iv, 1f);
        }
        return false;
    }

    private static boolean isInsideViewBounds(View v, MotionEvent event) {
        return event.getX() > 0 && event.getX() < v.getWidth() && event.getY() > 0
                && event.getY() < v.getHeight();
    }
}