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.view.ViewTreeObserver;
michael@0: import android.widget.ImageView;
michael@0: import java.lang.ref.WeakReference;
michael@0: 
michael@0: class DeferredRequestCreator implements ViewTreeObserver.OnPreDrawListener {
michael@0: 
michael@0:   final RequestCreator creator;
michael@0:   final WeakReference<ImageView> target;
michael@0:   Callback callback;
michael@0: 
michael@0:   DeferredRequestCreator(RequestCreator creator, ImageView target, Callback callback) {
michael@0:     this.creator = creator;
michael@0:     this.target = new WeakReference<ImageView>(target);
michael@0:     this.callback = callback;
michael@0:     target.getViewTreeObserver().addOnPreDrawListener(this);
michael@0:   }
michael@0: 
michael@0:   @Override public boolean onPreDraw() {
michael@0:     ImageView target = this.target.get();
michael@0:     if (target == null) {
michael@0:       return true;
michael@0:     }
michael@0:     ViewTreeObserver vto = target.getViewTreeObserver();
michael@0:     if (!vto.isAlive()) {
michael@0:       return true;
michael@0:     }
michael@0: 
michael@0:     int width = target.getMeasuredWidth();
michael@0:     int height = target.getMeasuredHeight();
michael@0: 
michael@0:     if (width <= 0 || height <= 0) {
michael@0:       return true;
michael@0:     }
michael@0: 
michael@0:     vto.removeOnPreDrawListener(this);
michael@0: 
michael@0:     this.creator.unfit().resize(width, height).into(target, callback);
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   void cancel() {
michael@0:     callback = null;
michael@0:     ImageView target = this.target.get();
michael@0:     if (target == null) {
michael@0:       return;
michael@0:     }
michael@0:     ViewTreeObserver vto = target.getViewTreeObserver();
michael@0:     if (!vto.isAlive()) {
michael@0:       return;
michael@0:     }
michael@0:     vto.removeOnPreDrawListener(this);
michael@0:   }
michael@0: }