michael@0: /*
michael@0:  * Copyright (C) 2013 Square, Inc.
michael@0:  *
michael@0:  * Licensed under the Apache License, Version 2.0 (the "License");
michael@0:  * you may not use this file except in compliance with the License.
michael@0:  * You may obtain a copy of the License at
michael@0:  *
michael@0:  *      http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing, software
michael@0:  * distributed under the License is distributed on an "AS IS" BASIS,
michael@0:  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
michael@0:  * See the License for the specific language governing permissions and
michael@0:  * limitations under the License.
michael@0:  */
michael@0: package com.squareup.picasso;
michael@0: 
michael@0: import android.graphics.Bitmap;
michael@0: import android.graphics.drawable.Drawable;
michael@0: 
michael@0: import static com.squareup.picasso.Picasso.LoadedFrom;
michael@0: 
michael@0: /**
michael@0:  * Represents an arbitrary listener for image loading.
michael@0:  * <p/>
michael@0:  * Objects implementing this class <strong>must</strong> have a working implementation of
michael@0:  * {@link #equals(Object)} and {@link #hashCode()} for proper storage internally. Instances of this
michael@0:  * interface will also be compared to determine if view recycling is occurring. It is recommended
michael@0:  * that you add this interface directly on to a custom view type when using in an adapter to ensure
michael@0:  * correct recycling behavior.
michael@0:  */
michael@0: public interface Target {
michael@0:   /**
michael@0:    * Callback when an image has been successfully loaded.
michael@0:    * <p/>
michael@0:    * <strong>Note:</strong> You must not recycle the bitmap.
michael@0:    */
michael@0:   void onBitmapLoaded(Bitmap bitmap, LoadedFrom from);
michael@0: 
michael@0:   /** Callback indicating the image could not be successfully loaded. */
michael@0:   void onBitmapFailed(Drawable errorDrawable);
michael@0: 
michael@0:   /** Callback invoked right before your request is submitted. */
michael@0:   void onPrepareLoad(Drawable placeHolderDrawable);
michael@0: }