How to animate setVisibility for an imagebutton on Android?

I have a layout that has a listview and imagebutton:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:l开发者_开发百科ayout_height="fill_parent"
    android:paddingTop="4px"
    android:background="@color/bgColor">

    <ImageButton
    android:id="@+id/imageButton"
    android:src="@drawable/button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginRight="0dp"
    android:layout_alignParentBottom="true"/>

    <ListView
    android:layout_above="@+id/imageButton" 
    android:id="@android:id/list"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:drawSelectorOnTop="false"
    android:background = "@drawable/list_bg"
    android:divider="@drawable/grade"
    android:dividerHeight ="1px"
    android:cacheColorHint="#00000000"
    android:fastScrollEnabled= "true"
    android:scrollingCache ="true"
    android:smoothScrollbar="false"
    >
   </ListView>
</RelativeLayout>

Based on user selection I am using this to hide or show the image button:

       ImageButton myButton = (ImageButton) findViewById(R.id.imageButton);
        myButton.setVisibility(View.GONE);

The code is working fine, however I would like to animate the hide/show process. How do I achieve this effect?

You can use the System animation fade in and fade out.

 Animation animFadeOut = AnimationUtils.loadAnimation(getApplicationContext(), android.R.anim.fade_out);
 Animation animFadeIn = AnimationUtils.loadAnimation(getApplicationContext(), android.R.anim.fade_in);
myButton.setAnimation(animFadeOut)
//if necessary then call:
myButton.setVisibility(View.GONE);

that should work

if you want to make your own animations: Look at Android Res and here is a very good tutorial for animations.

To show the button call this

AlphaAnimation fade_in = new AlphaAnimation(0.0f, 1.0f);
fade_in.setDuration(500);
fade_in.setAnimationListener(new AnimationListener()
{
    public void onAnimationStart(Animation arg0)
    {
    }
    public void onAnimationRepeat(Animation arg0)
    {
    }

    public void onAnimationEnd(Animation arg0)
    {
        myButton.setVisibility(View.VISIBLE);
    }
});
myButton.startAnimation(fade_in);

Then to hide the button:

AlphaAnimation fade_out = new AlphaAnimation(1.0f, 0.0f);
fade_out.setDuration(upcoming_animation_time);
fade_out.setAnimationListener(new AnimationListener()
{
    public void onAnimationStart(Animation arg0)
    {
    }
    public void onAnimationRepeat(Animation arg0)
    {
    }

    public void onAnimationEnd(Animation arg0)
    {
        myButton.setVisibility(View.GONE);
    }
});
myButton.startAnimation(fade_out);

Yes write your own animation listener and set it to the animation like this :

public class MyAnimationListener implements AnimationListener {
    private ImageButton mImgButton;

    public MyAnimationListener(ImageButton imgButton) {
        mImgButton = imgButton;
    }

    @Override
    public void onAnimationEnd(Animation animation) {
        mImgButton.setVisibility(View.GONE);

    }

    @Override
    public void onAnimationRepeat(Animation animation) {
        // TODO Auto - generated method stub

    }

    @Override
    public void onAnimationStart(Animation animation) {
        // TODO Auto - generated method stub

    }

}

Then set it to the animation with :

animation.setAnimationListener(new MyAnimationListener(myButton);

Thats it.

Check this example too (using ObjectAnimator):

ObjectAnimator animator = ObjectAnimator.ofFloat(myButton, View.ALPHA, 1f, 0f);
animator.setDuration(300); //ms
animator.start();
animator.addListener(new AnimatorListenerAdapter() {
    @Override
    public void onAnimationEnd(Animator animation) {
        myButton.setVisibility(GONE);
    }
});

You can easily switch to fade in effect too