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 android.transition;
  
  import android.animation.Animator;
  import android.animation.AnimatorSet;
  import android.animation.TypeEvaluator;
  import android.graphics.Bitmap;
  import android.graphics.Canvas;
  import android.graphics.Matrix;
  import android.graphics.Picture;
  import android.graphics.Rect;
  import android.graphics.RectF;
  import android.graphics.drawable.BitmapDrawable;
  import android.graphics.drawable.Drawable;
  import android.view.View;
  import android.view.ViewGroup;
  import android.widget.ImageView;
  
  /**
   * Static utility methods for Transitions.
   *
   * @hide
   */
  public class TransitionUtils {
      private static int MAX_IMAGE_SIZE = (1024 * 1024);
  
      static Animator mergeAnimators(Animator animator1, Animator animator2) {
          if (animator1 == null) {
              return animator2;
          } else if (animator2 == null) {
              return animator1;
          } else {
              AnimatorSet animatorSet = new AnimatorSet();
              animatorSet.playTogether(animator1, animator2);
              return animatorSet;
          }
      }
  
      public static Transition mergeTransitions(Transition... transitions) {
          int count = 0;
          int nonNullIndex = -1;
          for (int i = 0; i < transitions.length; i++) {
              if (transitions[i] != null) {
                  count++;
                  nonNullIndex = i;
              }
          }
  
          if (count == 0) {
              return null;
          }
  
          if (count == 1) {
              return transitions[nonNullIndex];
          }
  
          TransitionSet transitionSet = new TransitionSet();
          for (int i = 0; i < transitions.length; i++) {
              if (transitions[i] != null) {
                  transitionSet.addTransition(transitions[i]);
              }
          }
          return transitionSet;
      }
  
      /**
       * Creates a View using the bitmap copy of <code>view</code>. If <code>view</code> is large,
       * the copy will use a scaled bitmap of the given view.
       *
       * @param sceneRoot The ViewGroup in which the view copy will be displayed.
       * @param view The view to create a copy of.
       * @param parent The parent of view.
       */
      public static View copyViewImage(ViewGroup sceneRoot, View view, View parent) {
          Matrix matrix = new Matrix();
          matrix.setTranslate(-parent.getScrollX(), -parent.getScrollY());
          view.transformMatrixToGlobal(matrix);
          sceneRoot.transformMatrixToLocal(matrix);
          RectF bounds = new RectF(0, 0, view.getWidth(), view.getHeight());
          matrix.mapRect(bounds);
          int left = Math.round(bounds.left);
          int top = Math.round(bounds.top);
          int right = Math.round(bounds.right);
          int bottom = Math.round(bounds.bottom);
  
          ImageView copy = new ImageView(view.getContext());
          copy.setScaleType(ImageView.ScaleType.CENTER_CROP);
          Bitmap bitmap = createViewBitmap(view, matrix, bounds, sceneRoot);
          if (bitmap != null) {
              copy.setImageBitmap(bitmap);
          }
          int widthSpec = View.MeasureSpec.makeMeasureSpec(right - left, View.MeasureSpec.EXACTLY);
          int heightSpec = View.MeasureSpec.makeMeasureSpec(bottom - top, View.MeasureSpec.EXACTLY);
          copy.measure(widthSpec, heightSpec);
          copy.layout(left, top, right, bottom);
          return copy;
      }
  
      /**
       * Get a copy of bitmap of given drawable, return null if intrinsic size is zero
       */
      public static Bitmap createDrawableBitmap(Drawable drawable, View hostView) {
          int width = drawable.getIntrinsicWidth();
          int height = drawable.getIntrinsicHeight();
          if (width <= 0 || height <= 0) {
              return null;
          }
          float scale = Math.min(1f, ((float)MAX_IMAGE_SIZE) / (width * height));
          if (drawable instanceof BitmapDrawable && scale == 1f) {
              // return same bitmap if scale down not needed
              return ((BitmapDrawable) drawable).getBitmap();
          }
          int bitmapWidth = (int) (width * scale);
          int bitmapHeight = (int) (height * scale);
          final Picture picture = new Picture();
          final Canvas canvas = picture.beginRecording(width, height);
          // Do stuff with the canvas
          Rect existingBounds = drawable.getBounds();
          int left = existingBounds.left;
          int top = existingBounds.top;
          int right = existingBounds.right;
          int bottom = existingBounds.bottom;
          drawable.setBounds(0, 0, bitmapWidth, bitmapHeight);
          drawable.draw(canvas);
          drawable.setBounds(left, top, right, bottom);
          picture.endRecording();
          return Bitmap.createBitmap(picture);
      }
  
      /**
       * Creates a Bitmap of the given view, using the Matrix matrix to transform to the local
       * coordinates. <code>matrix</code> will be modified during the bitmap creation.
       *
       * <p>If the bitmap is large, it will be scaled uniformly down to at most 1MB size.</p>
       * @param view The view to create a bitmap for.
       * @param matrix The matrix converting the view local coordinates to the coordinates that
       *               the bitmap will be displayed in. <code>matrix</code> will be modified before
       *               returning.
       * @param bounds The bounds of the bitmap in the destination coordinate system (where the
       *               view should be presented. Typically, this is matrix.mapRect(viewBounds);
       * @param sceneRoot A ViewGroup that is attached to the window to temporarily contain the view
       *                  if it isn't attached to the window.
       * @return A bitmap of the given view or null if bounds has no width or height.
       */
      public static Bitmap createViewBitmap(View view, Matrix matrix, RectF bounds,
              ViewGroup sceneRoot) {
          final boolean addToOverlay = !view.isAttachedToWindow();
          ViewGroup parent = null;
          int indexInParent = 0;
          if (addToOverlay) {
              if (sceneRoot == null || !sceneRoot.isAttachedToWindow()) {
                  return null;
              }
              parent = (ViewGroup) view.getParent();
              indexInParent = parent.indexOfChild(view);
              sceneRoot.getOverlay().add(view);
          }
          Bitmap bitmap = null;
          int bitmapWidth = Math.round(bounds.width());
          int bitmapHeight = Math.round(bounds.height());
          if (bitmapWidth > 0 && bitmapHeight > 0) {
              float scale = Math.min(1f, ((float) MAX_IMAGE_SIZE) / (bitmapWidth * bitmapHeight));
              bitmapWidth *= scale;
              bitmapHeight *= scale;
              matrix.postTranslate(-bounds.left, -bounds.top);
              matrix.postScale(scale, scale);
  
              final Picture picture = new Picture();
              final Canvas canvas = picture.beginRecording(bitmapWidth, bitmapHeight);
              canvas.concat(matrix);
              view.draw(canvas);
              picture.endRecording();
              bitmap = Bitmap.createBitmap(picture);
          }
          if (addToOverlay) {
              sceneRoot.getOverlay().remove(view);
              parent.addView(view, indexInParent);
          }
          return bitmap;
      }
  
      public static class MatrixEvaluator implements TypeEvaluator<Matrix> {
  
          float[] mTempStartValues = new float[9];
  
          float[] mTempEndValues = new float[9];
  
          Matrix mTempMatrix = new Matrix();
  
          @Override
          public Matrix evaluate(float fraction, Matrix startValue, Matrix endValue) {
              startValue.getValues(mTempStartValues);
              endValue.getValues(mTempEndValues);
              for (int i = 0; i < 9; i++) {
                  float diff = mTempEndValues[i] - mTempStartValues[i];
                  mTempEndValues[i] = mTempStartValues[i] + (fraction * diff);
              }
              mTempMatrix.setValues(mTempEndValues);
              return mTempMatrix;
          }
      }
  }
  