Crossfading using TransitionDrawable not working on android

Here's an example IF you have 2 drawables and want to animate their transition in some ImageView:

package com.example.app;

import android.app.Activity;
import android.content.res.Resources;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.TransitionDrawable;
import android.os.Bundle;
import android.widget.ImageView;

 class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Drawable backgrounds[] = new Drawable[2];
        Resources res = getResources();
        backgrounds[0] = res.getDrawable(android.R.drawable.btn_star_big_on);
        backgrounds[1] = res.getDrawable(android.R.drawable.btn_star_big_off);

        TransitionDrawable crossfader = new TransitionDrawable(backgrounds);

        ImageView image = (ImageView)findViewById(R.id.image);
        image.setImageDrawable(crossfader);

        crossfader.startTransition(3000);

    }
}

Then if you want to transition back to the original image you can call

// Make sure the transition occurred
crossfader.startTransition(0);
// Reverse transition
crossfader.reverseTransition(3000);

Please correct me if I misunderstood your question.


Maybe you like this one
- res/drawable/transition.xml:

<?xml version="1.0" encoding="utf-8"?>
<transition xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@drawable/on" />
    <item android:drawable="@drawable/off" />
</transition>

ImageView:

<ImageButton android:id="@+id/button"
    android:layout_height="wrap_content"
    android:layout_width="wrap_content"
    android:src="@drawable/transition" /> 

Javacode:

ImageButton button = (ImageButton) findViewById(R.id.button);
TransitionDrawable drawable = (TransitionDrawable) button.getDrawable();
drawable.startTransition(500);

If it is helpfull, you can see Google-Dev:

http://developer.android.com/guide/topics/resources/drawable-resource.html


If you are using Vectors, your VectorDrawables won't be cross-faded in the TransitionDrawable.

You'll need to convert them into BitmapDrawables first.

See my answer here https://stackoverflow.com/a/54583929/114549 for an example


You should use setCrossFadeEnabled propery

final TransitionDrawable briefcaseTransition = (TransitionDrawable) briefcase.getDrawable();
briefcaseTransition.setCrossFadeEnabled(true);
briefcaseTransition.startTransition(500);