Glide: laden drawable aber nicht Maßstab Platzhalter

Re: Gregs Kommentar:
Ich gab es einen weiteren Schuss (mit fast einem Jahr extra-XP) und kam mit dieser:

<ImageView android:scaleType="center" ... />

ähnlich wie meine andere Lösung und die folgende animation-wrapper:

...
    .fitCenter()
    .animate(new PaddingAnimationFactory<>(new DrawableCrossFadeFactory<GlideDrawable>(2000)))
    .into(imageView)
;

class PaddingAnimationFactory<T extends Drawable> implements GlideAnimationFactory<T> {
    private final DrawableCrossFadeFactory<T> realFactory;
    @Override public GlideAnimation<T> build(boolean isFromMemoryCache, boolean isFirstResource) {
        return new PaddingAnimation<>(realFactory.build(isFromMemoryCache, isFirstResource));
    }
}

class PaddingAnimation<T extends Drawable> implements GlideAnimation<T> {
    private final GlideAnimation<? super T> realAnimation;
    @Override public boolean animate(T current, final ViewAdapter adapter) {
        int width = current.getIntrinsicWidth();
        int height = current.getIntrinsicHeight();
        return realAnimation.animate(current, new PaddingViewAdapter(adapter, width, height));
    }
}

class PaddingViewAdapter implements ViewAdapter {
    @Override public Drawable getCurrentDrawable() {
        Drawable drawable = realAdapter.getCurrentDrawable();
        if (drawable != null) {
            int padX = Math.max(0, targetWidth - drawable.getIntrinsicWidth()) / 2;
            int padY = Math.max(0, targetHeight - drawable.getIntrinsicHeight()) / 2;
            if (padX != 0 || padY != 0) {
                drawable = new InsetDrawable(drawable, padX, padY, padX, padY);
            }
        }
        return drawable;
    }
    @Override public void setDrawable(Drawable drawable) {
        if (VERSION.SDK_INT >= VERSION_CODES.M && drawable instanceof TransitionDrawable) {
            //For some reason padding is taken into account differently on M than before in LayerDrawable
            //PaddingMode was introduced in 21 and gravity in 23, I think NO_GRAVITY default may play
            //a role in this, but didn't have time to dig deeper than this.
            ((TransitionDrawable)drawable).setPaddingMode(TransitionDrawable.PADDING_MODE_STACK);
        }
        realAdapter.setDrawable(drawable);
    }
}

Triviale Teile der Implementierungen angegeben werden, wird jede Klasse einen Konstruktor initialisiert die Felder von Argumenten. Vollständigen code, verfügbar auf GitHub in TWiStErRob/glide-Unterstützung.

Wenn Sie stecken in einer älteren version von Glide (vor 3.8.0), der gleiche Effekt kann erreicht werden durch:

.fitCenter()
.placeholder(R.drawable.glide_placeholder)
.crossFade(2000)
.into(new GlideDrawableImageViewTarget(imageView) {
    @Override public void onResourceReady(GlideDrawable resource,
            GlideAnimation<? super GlideDrawable> animation) {
        super.onResourceReady(resource, new PaddingAnimation<>(animation));
    }
})

Beachten Sie, wie die beiden Lösungen erfordern die gleiche Anzahl von Klassen, aber die post-3.8.0-Lösung hat eine bessere Trennung von Bedenken, und es kann zwischengespeichert werden, in einer variable zu verhindern, dass Zuweisungen.

InformationsquelleAutor der Antwort TWiStErRob

Mache ich es wie unten erwähnt:

Die Idee ist, um die Skala zu geben, wie Sie durch den Platzhalter zunächst & attach listener um den Maßstab zu ändern geben Sie wieder, wie Sie durch die heruntergeladene Bild, nach der das Bild heruntergeladen wird.

//ivBuilderLogo = Target ImageView
//Set the scale type to as required by your place holder
//ScaleType.CENTER_INSIDE will maintain aspect ration and fit the placeholder inside the image view
holder.ivBuilderLogo.setScaleType(ImageView.ScaleType.CENTER_INSIDE); 

//AnimationDrawable is required when you are using transition drawables
//You can directly send resource id to glide if your placeholder is static
//However if you are using GIFs, it is better to create a transition drawable in xml 
//& use it as shown in this example
AnimationDrawable animationDrawable;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)
     animationDrawable=(AnimationDrawable)context.getDrawable(R.drawable.anim_image_placeholder);
else
     animationDrawable=(AnimationDrawable)context.getResources().getDrawable(R.drawable.anim_image_placeholder);
animationDrawable.start();

Glide.with(context).load(logo_url)
                   .placeholder(animationDrawable)
                   .listener(new RequestListener<String, GlideDrawable>() {
                        @Override
                        public boolean onException(Exception e, String model, Target<GlideDrawable> target, boolean isFirstResource)
                        {
                           return false;
                        }

                        //This is invoked when your image is downloaded and is ready 
                        //to be loaded to the image view
                        @Override
                        public boolean onResourceReady(GlideDrawable resource, String model, Target<GlideDrawable> target, boolean isFromMemoryCache, boolean isFirstResource)
                        {   
                        //This is used to remove the placeholder image from your ImageView 
                        //and load the downloaded image with desired scale-type(FIT_XY in this case)
                        //Changing the scale type from 'CENTER_INSIDE' to 'FIT_XY' 
                        //will stretch the placeholder for a (very) short duration,
                        //till the downloaded image is loaded
                        //setImageResource(0) removes the placeholder from the image-view 
                        //before setting the scale type to FIT_XY and ensures that the UX 
                        //is not spoiled, even for a (very) short duration
                            holder.ivBuilderLogo.setImageResource(0);
                            holder.ivBuilderLogo.setScaleType(ImageView.ScaleType.FIT_XY);
                            return false;
                        }
                    })
                    .into( holder.ivBuilderLogo);

Mein übergang drawable (R. drawable.anim_image_placeholder) :

(nicht erforderlich, wenn die Verwendung einer statischen Bild)

<?xml version="1.0" encoding="utf-8"?>
<animation-list
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:oneshot="false">
    <item android:drawable="@drawable/loading_frame1" android:duration="100" />
    <!--<item android:drawable="@drawable/loading_frame2" android:duration="100" />-->
    <item android:drawable="@drawable/loading_frame3" android:duration="100" />
    <!--<item android:drawable="@drawable/loading_frame4" android:duration="100" />-->
    <item android:drawable="@drawable/loading_frame5" android:duration="100" />
    <!--<item android:drawable="@drawable/loading_frame6" android:duration="100" />-->
    <item android:drawable="@drawable/loading_frame7" android:duration="100" />
    <!--<item android:drawable="@drawable/loading_frame8" android:duration="100" />-->
    <item android:drawable="@drawable/loading_frame9" android:duration="100" />
    <!--<item android:drawable="@drawable/loading_frame10" android:duration="100" />-->
</animation-list>

InformationsquelleAutor der Antwort Swas_99