ImageViewBitmapTask.java

/*
 * Copyright 2012 Kevin Sawicki <kevinsawicki@gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.github.kevinsawicki.wishlist;

import android.graphics.Bitmap;
import android.view.animation.AnimationUtils;
import android.widget.ImageView;

import java.lang.ref.WeakReference;

/**
 * Task to decode a bitmap and set it on an {@link ImageView}
 */
public class ImageViewBitmapTask extends DecodeBitmapTask {

  /**
   * View being updated
   */
  protected final WeakReference<ImageView> view;

  /**
   * Whether or not images are faded in when set
   */
  protected boolean fadeIn = true;

  /**
   * Create task to set bitmap at path on given image view
   *
   * @param maxWidth
   * @param maxHeight
   * @param path
   * @param view
   */
  public ImageViewBitmapTask(final int maxWidth, final int maxHeight,
      final String path, final ImageView view) {
    super(maxWidth, maxHeight, path);

    this.view = new WeakReference<ImageView>(view);
  }

  /**
   * @param fadeIn
   * @return this task
   */
  public ImageViewBitmapTask setFadeIn(final boolean fadeIn) {
    this.fadeIn = fadeIn;
    return this;
  }

  @Override
  protected void onPreExecute() {
    super.onPreExecute();

    ImageView view = getView();
    if (view == null)
      return;

    view.setImageDrawable(null);
    if (view.getAnimation() != null)
      view.clearAnimation();
    view.setTag(this);
  }

  /**
   * Get view being updated
   *
   * @return view
   */
  protected ImageView getView() {
    return view.get();
  }

  @Override
  protected void onPostExecute(final Bitmap result) {
    super.onPostExecute(result);

    ImageView view = getView();
    if (view == null)
      return;

    if (!equals(view.getTag()))
      return;

    view.setTag(null);
    if (result != null) {
      if (fadeIn && view.getAnimation() == null)
        view.startAnimation(AnimationUtils.loadAnimation(view.getContext(),
            android.R.anim.fade_in));
      view.setImageBitmap(result);
    } else {
      view.setImageDrawable(null);
      view.clearAnimation();
    }
  }
}