Fade in animation while loading image Using Picasso

Question

I want to show a fade effect when image is loading on Imageview. I am using picasso to cache image and display in image view. I have searched alot for this but couldnt find

Answer 1

Quoting Jake Wharton's answer here:

If the image comes from anywhere except the memory cache the fade should be automatically applied.

If you check the PicassoDrawable class

boolean fade = loadedFrom != MEMORY && !noFade;
if (fade) {
  this.placeholder = placeholder;
  animating = true;
  startTimeMillis = SystemClock.uptimeMillis();
}
.
.
.
@Override public void draw(Canvas canvas) {
if (!animating) {
  super.draw(canvas);
} else {
.
.
.

fade effect is already applied for images loaded from n/w and not memory/cache and FADE_DURATION = 200f; //ms

To force fade, again quoting jake wharton's answer here:

You can specify noFade() and then always play an animation in the image loaded callback. You can also rely on the callback being called synchronously to determine if an animation needs played.

final AtomicBoolean playAnimation = new AtomicBoolean(true);
Picasso.with(context).load(..).into(imageView, new Callback() {
  @Override public void onLoad() {
    if (playAnimation.get()) {
      //play fade
      Animation fadeOut = new AlphaAnimation(0, 1);
      fadeOut.setInterpolator(new AccelerateInterpolator());
      fadeOut.setDuration(1000);
      imageView.startAnimation(fadeOut);

      Animation fadeOutPlaceholder = new AlphaAnimation(1, 0);
      fadeOutPlaceholder.setInterpolator(new AccelerateInterpolator());
      fadeOutPlaceholder.setDuration(1000);
      placeHolderImageView.startAnimation(fadeOutPlaceholder);
    }
  }
  //..
});
playAnimation.set(false);