content: /*
   * Copyright (C) 2014 The Android Open Source Project
   *
   * 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.example.android.activityscenetransitionbasic;
  
  import android.os.Build;
  import android.os.Bundle;
  import android.transition.Transition;
  import android.widget.ImageView;
  import android.widget.TextView;
  
  import androidx.annotation.RequiresApi;
  import androidx.appcompat.app.AppCompatActivity;
  import androidx.core.view.ViewCompat;
  
  import com.squareup.picasso.Picasso;
  
  /**
   * Our secondary Activity which is launched from {@link MainActivity}. Has a simple detail UI
   * which has a large banner image, title and body text.
   */
  public class DetailActivity extends AppCompatActivity {
  
      // Extra name for the ID parameter
      public static final String EXTRA_PARAM_ID = "detail:_id";
  
      // View name of the header image. Used for activity scene transitions
      public static final String VIEW_NAME_HEADER_IMAGE = "detail:header:image";
  
      // View name of the header title. Used for activity scene transitions
      public static final String VIEW_NAME_HEADER_TITLE = "detail:header:title";
  
      private ImageView mHeaderImageView;
      private TextView mHeaderTitle;
  
      private Item mItem;
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.details);
  
          // Retrieve the correct Item instance, using the ID provided in the Intent
          mItem = Item.getItem(getIntent().getIntExtra(EXTRA_PARAM_ID, 0));
  
          mHeaderImageView = findViewById(R.id.imageview_header);
          mHeaderTitle = findViewById(R.id.textview_title);
  
          // BEGIN_INCLUDE(detail_set_view_name)
          /*
           * Set the name of the view's which will be transition to, using the static values above.
           * This could be done in the layout XML, but exposing it via static variables allows easy
           * querying from other Activities
           */
          ViewCompat.setTransitionName(mHeaderImageView, VIEW_NAME_HEADER_IMAGE);
          ViewCompat.setTransitionName(mHeaderTitle, VIEW_NAME_HEADER_TITLE);
          // END_INCLUDE(detail_set_view_name)
  
          loadItem();
      }
  
      private void loadItem() {
          // Set the title TextView to the item's name and author
          mHeaderTitle.setText(getString(R.string.image_header, mItem.getName(), mItem.getAuthor()));
  
          if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP && addTransitionListener()) {
              // If we're running on Lollipop and we have added a listener to the shared element
              // transition, load the thumbnail. The listener will load the full-size image when
              // the transition is complete.
              loadThumbnail();
          } else {
              // If all other cases we should just load the full-size image now
              loadFullSizeImage();
          }
      }
  
      /**
       * Load the item's thumbnail image into our {@link ImageView}.
       */
      private void loadThumbnail() {
          Picasso.with(mHeaderImageView.getContext())
                  .load(mItem.getThumbnailUrl())
                  .noFade()
                  .into(mHeaderImageView);
      }
  
      /**
       * Load the item's full-size image into our {@link ImageView}.
       */
      private void loadFullSizeImage() {
          Picasso.with(mHeaderImageView.getContext())
                  .load(mItem.getPhotoUrl())
                  .noFade()
                  .noPlaceholder()
                  .into(mHeaderImageView);
      }
  
      /**
       * Try and add a {@link Transition.TransitionListener} to the entering shared element
       * {@link Transition}. We do this so that we can load the full-size image after the transition
       * has completed.
       *
       * @return true if we were successful in adding a listener to the enter transition
       */
      @RequiresApi(21)
      private boolean addTransitionListener() {
          final Transition transition = getWindow().getSharedElementEnterTransition();
  
          if (transition != null) {
              // There is an entering shared element transition so add a listener to it
              transition.addListener(new Transition.TransitionListener() {
                  @Override
                  public void onTransitionEnd(Transition transition) {
                      // As the transition has ended, we can now load the full-size image
                      loadFullSizeImage();
  
                      // Make sure we remove ourselves as a listener
                      transition.removeListener(this);
                  }
  
                  @Override
                  public void onTransitionStart(Transition transition) {
                      // No-op
                  }
  
                  @Override
                  public void onTransitionCancel(Transition transition) {
                      // Make sure we remove ourselves as a listener
                      transition.removeListener(this);
                  }
  
                  @Override
                  public void onTransitionPause(Transition transition) {
                      // No-op
                  }
  
                  @Override
                  public void onTransitionResume(Transition transition) {
                      // No-op
                  }
              });
              return true;
          }
  
          // If we reach here then we have not added a listener
          return false;
      }
  
  }
  