使用毕加索获得带有位图的回调

Found the answer on github in case anyone is wondering:

private Target target = new Target() {
@Override
public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
}


@Override
public void onBitmapFailed(Drawable errorDrawable) {
}


@Override
public void onPrepareLoad(Drawable placeHolderDrawable) {
}
}


private void someMethod() {
Picasso.with(this).load("url").into(target);
}


@Override
public void onDestroy() {  // could be in onPause or onStop
Picasso.with(this).cancelRequest(target);
super.onDestroy();
}

The post recommends not using an anonymous callback, and instead using an instance variable for target.

taken from here:

Picasso.with(this)
.load(url)
.into(new Target() {
@Override
public void onBitmapLoaded (final Bitmap bitmap, Picasso.LoadedFrom from){
/* Save the bitmap or do something with it here */


//Set it in the ImageView
theView.setImageBitmap(bitmap);
}
});

Updated (May 04, 2016):

            Picasso.with(this)
.load(youUrl)
.into(new Target() {
@Override
public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {


}


@Override
public void onBitmapFailed(Drawable errorDrawable) {


}


@Override
public void onPrepareLoad(Drawable placeHolderDrawable) {


}
});

Updated (November 22, 2016)

or using a strong reference for Target so that it wont be garbage collected

Target target = new Target() {
@Override
public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {


}


@Override
public void onBitmapFailed(Drawable errorDrawable) {


}


@Override
public void onPrepareLoad(Drawable placeHolderDrawable) {


}
};




void foo() {
Picasso.with(getContext()).load(getUrl()).into(target);
}

Kotlin

object: com.squareup.picasso.Target {
override fun onBitmapFailed(e: java.lang.Exception?, errorDrawable: Drawable?) {
TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
}


override fun onPrepareLoad(placeHolderDrawable: Drawable?) {
TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
}


override fun onBitmapLoaded(bitmap: Bitmap?, from: Picasso.LoadedFrom?) {


}
}

I thought maybe some of you would like an RxJava version of the above answer... Here it is:

    public static Observable<Bitmap> loadBitmap(Picasso picasso, String imageUrl) {
return Observable.create(new Observable.OnSubscribe<Bitmap>() {
@Override
public void call(Subscriber<? super Bitmap> subscriber) {
Target target = new Target() {
@Override
public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
subscriber.onNext(bitmap);
subscriber.onCompleted();
}


@Override
public void onBitmapFailed(Drawable errorDrawable) {
subscriber.onError(new Exception("failed to load " + imageUrl));
}


@Override
public void onPrepareLoad(Drawable placeHolderDrawable) {
}
};
subscriber.add(new Subscription() {
private boolean unSubscribed;


@Override
public void unsubscribe() {
picasso.cancelRequest(target);
unSubscribed = true;
}


@Override
public boolean isUnsubscribed() {
return unSubscribed;
}
});
picasso.load(imageUrl).into(target);
}
});
}

P.S. When subscribing, store the subscription reference on your activity, otherwise, target will be GC'd before you receive a response...

What can be easy than next:

val url: String = "https://...."
val bitmap: Bitmap = Picasso.with(context).load(url).get()

Should be called from not the main thread!

or with RxJava 2:

fun getBitmapSingle(picasso: Picasso, url: String): Single<Bitmap> = Single.create {
try {
if (!it.isDisposed) {
val bitmap: Bitmap = picasso.load(url).get()
it.onSuccess(bitmap)
}
} catch (e: Throwable) {
it.onError(e)
}
}

Retrieve Bitmap:

getBitmapSingle(Picasso.with(context), "https:/...")
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe({ bitmap ->
// val drawable = BitmapDrawable(context, bitmap)
}, Throwable::printStackTrace)

I used Picasso v.2.5.2