android – 加载图像时淡入动画使用Picasso

我想在Imageview上加载图像时显示淡入淡出效果.我正在使用毕加索来缓存图像并在图像视图中显示.我已经搜索了很多,但无法找到任何解决方案.

我之前使用过,我知道在某些版本中他们有.fade(int Duration)方法在加载时淡化图像,但我再也找不到这种方法了.

这就是我现在正在做的事情

Picasso.with(context)
                .load(viewHolder.data.imageList.get(0).url)
                .networkPolicy(NetworkPolicy.OFFLINE)
                .placeholder(R.drawable.a_place_holder_list_view)
                .error(R.drawable.a_place_holder_list_view)
                .into(viewHolder.ivUser, context.loadImage(viewHolder.ivUser, viewHolder.data.imageList.get(0).url));


public Callback loadImage(RoundedImageView ivUser, String url) {
    return new callback(ivUser, url);
}

public class callback implements Callback {

    RoundedImageView imageView;
    String url;

    public callback(RoundedImageView imageView, String url) {
        this.imageView = imageView;
        this.url = url;
    }

    @Override
    public void onSuccess() {

    }

    @Override
    public void one rror() {
        Picasso.with(BaseActivity.this)
                .load(url)
                .placeholder(R.drawable.a_place_holder_list_view)
                .error(R.drawable.a_place_holder_list_view)
                .into(imageView, new Callback() {
                    @Override
                    public void onSuccess() {

                    }

                    @Override
                    public void one rror() {
                        Log.v("Picasso", "Could not fetch image");
                    }
                });
    }
}

请帮助我,我已经被困在这很长一段时间了.
提前致谢.

解决方法:

引用杰克沃顿的回答here：

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

如果你检查PicassoDrawable班

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 {
.
.
.

淡入淡出效果已经应用于从n / w而不是内存/缓存加载的图像
和FADE_DURATION = 200f; //女士

为了强制淡出,再次引用杰克沃顿的回答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 onl oad() {
    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);

标签：fade,image-loading,android,picasso
来源： https://codeday.me/bug/20191007/1868450.html