src/com/android/wallpaper/picker/ImagePreviewFragment.java - platform/packages/apps/WallpaperPicker2 - Git at Google

 /*
  * Copyright (C) 2019 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.android.wallpaper.picker;

 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
 import android.app.Activity;
 import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.Bitmap.Config;
 import android.graphics.Color;
 import android.graphics.Point;
 import android.graphics.PointF;
 import android.graphics.Rect;
 import android.os.Bundle;
 import android.view.Display;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.ImageView;

 import androidx.annotation.Nullable;
 import androidx.fragment.app.FragmentActivity;

 import com.android.wallpaper.R;
 import com.android.wallpaper.asset.Asset;
 import com.android.wallpaper.module.WallpaperPersister.Destination;
 import com.android.wallpaper.module.WallpaperPersister.SetWallpaperCallback;
 import com.android.wallpaper.util.ScreenSizeCalculator;
 import com.android.wallpaper.util.WallpaperCropUtils;

 import com.bumptech.glide.Glide;
 import com.bumptech.glide.MemoryCategory;
 import com.davemorrissey.labs.subscaleview.ImageSource;
 import com.davemorrissey.labs.subscaleview.SubsamplingScaleImageView;
 import com.google.android.material.bottomsheet.BottomSheetBehavior;

 /**
  * Fragment which displays the UI for previewing an individual static wallpaper and its attribution
  * information.
  */
 public class ImagePreviewFragment extends PreviewFragment {

     private static final float DEFAULT_WALLPAPER_MAX_ZOOM = 8f;

     private SubsamplingScaleImageView mFullResImageView;
     private Asset mWallpaperAsset;
     private Point mDefaultCropSurfaceSize;
     private Point mScreenSize;
     private Point mRawWallpaperSize; // Native size of wallpaper image.
     private ImageView mLowResImageView;

     private InfoPageController mInfoPageController;

     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         mWallpaperAsset = mWallpaper.getAsset(requireContext().getApplicationContext());
     }

     @Override
     protected int getLayoutResId() {
         return R.layout.fragment_image_preview;
     }


     protected int getBottomSheetResId() {
         return R.id.bottom_sheet;
     }

     @Override
     protected int getLoadingIndicatorResId() {
         return R.id.loading_indicator;
     }

     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
         View view = super.onCreateView(inflater, container, savedInstanceState);

         Activity activity = requireActivity();

         mFullResImageView = view.findViewById(R.id.full_res_image);

         mInfoPageController = new InfoPageController(view.findViewById(R.id.page_info),
                 mPreviewMode);

         mLowResImageView = view.findViewById(R.id.low_res_image);

         // Trim some memory from Glide to make room for the full-size image in this fragment.
         Glide.get(activity).setMemoryCategory(MemoryCategory.LOW);

         mDefaultCropSurfaceSize = WallpaperCropUtils.getDefaultCropSurfaceSize(
                 getResources(), activity.getWindowManager().getDefaultDisplay());
         mScreenSize = ScreenSizeCalculator.getInstance().getScreenSize(
                 activity.getWindowManager().getDefaultDisplay());

         // Load a low-res placeholder image if there's a thumbnail available from the asset that can
         // be shown to the user more quickly than the full-sized image.
         if (mWallpaperAsset.hasLowResDataSource()) {
             mWallpaperAsset.loadLowResDrawable(activity, mLowResImageView, Color.BLACK,
                     new WallpaperPreviewBitmapTransformation(activity.getApplicationContext(),
                             isRtl()));
         }

         mWallpaperAsset.decodeRawDimensions(getActivity(), dimensions -> {
             // Don't continue loading the wallpaper if the Fragment is detached.
             if (getActivity() == null) {
                 return;
             }

             // Return early and show a dialog if dimensions are null (signaling a decoding error).
             if (dimensions == null) {
                 showLoadWallpaperErrorDialog();
                 return;
             }

             mRawWallpaperSize = dimensions;
             setUpExploreIntent(ImagePreviewFragment.this::initFullResView);
         });

         setUpLoadingIndicator();

         return view;
     }

     @Override
     protected void setUpBottomSheetView(ViewGroup bottomSheet) {
         // Nothing needed here.
     }

     @Override
     protected boolean isLoaded() {
         return mFullResImageView != null && mFullResImageView.hasImage();
     }

     @Override
     public void onClickOk() {
         FragmentActivity activity = getActivity();
         if (activity != null) {
             activity.finish();
         }
     }

     @Override
     public void onDestroy() {
         super.onDestroy();
         if (mLoadingProgressBar != null) {
             mLoadingProgressBar.hide();
         }
         mFullResImageView.recycle();
     }

     @Override
     public void onSaveInstanceState(Bundle outState) {
         super.onSaveInstanceState(outState);

         final BottomSheetBehavior bottomSheetBehavior = BottomSheetBehavior.from(mBottomSheet);
         outState.putInt(KEY_BOTTOM_SHEET_STATE, bottomSheetBehavior.getState());
     }

     @Override
     protected void setBottomSheetContentAlpha(float alpha) {
         mInfoPageController.setContentAlpha(alpha);
     }

     @Override
     protected CharSequence getExploreButtonLabel(Context context) {
         return context.getString(mWallpaper.getActionLabelRes(context));
     }

     /**
      * Initializes MosaicView by initializing tiling, setting a fallback page bitmap, and
      * initializing a zoom-scroll observer and click listener.
      */
     private void initFullResView() {
         mFullResImageView.setMinimumScaleType(SubsamplingScaleImageView.SCALE_TYPE_CENTER_CROP);

         // Set a solid black "page bitmap" so MosaicView draws a black background while waiting
         // for the image to load or a transparent one if a thumbnail already loaded.
         Bitmap blackBitmap = Bitmap.createBitmap(1, 1, Config.ARGB_8888);
         int color = (mLowResImageView.getDrawable() == null) ? Color.BLACK : Color.TRANSPARENT;
         blackBitmap.setPixel(0, 0, color);
         mFullResImageView.setImage(ImageSource.bitmap(blackBitmap));

         // Then set a fallback "page bitmap" to cover the whole MosaicView, which is an actual
         // (lower res) version of the image to be displayed.
         Point targetPageBitmapSize = new Point(mRawWallpaperSize);
         mWallpaperAsset.decodeBitmap(targetPageBitmapSize.x, targetPageBitmapSize.y,
                 pageBitmap -> {
                     // Check that the activity is still around since the decoding task started.
                     if (getActivity() == null) {
                         return;
                     }

                     // Some of these may be null depending on if the Fragment is paused, stopped,
                     // or destroyed.
                     if (mLoadingProgressBar != null) {
                         mLoadingProgressBar.hide();
                     }
                     // The page bitmap may be null if there was a decoding error, so show an
                     // error dialog.
                     if (pageBitmap == null) {
                         showLoadWallpaperErrorDialog();
                         return;
                     }
                     if (mFullResImageView != null) {
                         // Set page bitmap.
                         mFullResImageView.setImage(ImageSource.bitmap(pageBitmap));

                         setDefaultWallpaperZoomAndScroll();
                         crossFadeInMosaicView();
                     }
                     getActivity().invalidateOptionsMenu();

                     populateInfoPage(mInfoPageController);
                 });
     }

     /**
      * Makes the MosaicView visible with an alpha fade-in animation while fading out the loading
      * indicator.
      */
     private void crossFadeInMosaicView() {
         long shortAnimationDuration = getResources().getInteger(
                 android.R.integer.config_shortAnimTime);

         mFullResImageView.setAlpha(0f);
         mFullResImageView.animate()
                 .alpha(1f)
                 .setDuration(shortAnimationDuration)
                 .setListener(new AnimatorListenerAdapter() {
                     @Override
                     public void onAnimationEnd(Animator animation) {
                         // Clear the thumbnail bitmap reference to save memory since it's no longer
                         // visible.
                         if (mLowResImageView != null) {
                             mLowResImageView.setImageBitmap(null);
                         }
                     }
                 });

         mLoadingProgressBar.animate()
                 .alpha(0f)
                 .setDuration(shortAnimationDuration)
                 .setListener(new AnimatorListenerAdapter() {
                     @Override
                     public void onAnimationEnd(Animator animation) {
                         if (mLoadingProgressBar != null) {
                             mLoadingProgressBar.hide();
                         }
                     }
                 });
     }

     /**
      * Sets the default wallpaper zoom and scroll position based on a "crop surface"
      * (with extra width to account for parallax) superimposed on the screen. Shows as much of the
      * wallpaper as possible on the crop surface and align screen to crop surface such that the
      * default preview matches what would be seen by the user in the left-most home screen.
      *
      * <p>This method is called once in the Fragment lifecycle after the wallpaper asset has loaded
      * and rendered to the layout.
      */
     private void setDefaultWallpaperZoomAndScroll() {
         // Determine minimum zoom to fit maximum visible area of wallpaper on crop surface.
         float defaultWallpaperZoom =
                 WallpaperCropUtils.calculateMinZoom(mRawWallpaperSize, mDefaultCropSurfaceSize);
         float minWallpaperZoom =
                 WallpaperCropUtils.calculateMinZoom(mRawWallpaperSize, mScreenSize);

         Point screenToCropSurfacePosition = WallpaperCropUtils.calculateCenterPosition(
                 mDefaultCropSurfaceSize, mScreenSize, true /* alignStart */, isRtl());
         Point zoomedWallpaperSize = new Point(
                 Math.round(mRawWallpaperSize.x * defaultWallpaperZoom),
                 Math.round(mRawWallpaperSize.y * defaultWallpaperZoom));
         Point cropSurfaceToWallpaperPosition = WallpaperCropUtils.calculateCenterPosition(
                 zoomedWallpaperSize, mDefaultCropSurfaceSize, false /* alignStart */, isRtl());

         // Set min wallpaper zoom and max zoom on MosaicView widget.
         mFullResImageView.setMaxScale(Math.max(DEFAULT_WALLPAPER_MAX_ZOOM, defaultWallpaperZoom));
         mFullResImageView.setMinScale(minWallpaperZoom);

         // Set center to composite positioning between scaled wallpaper and screen.
         PointF centerPosition = new PointF(
                 mRawWallpaperSize.x / 2f,
                 mRawWallpaperSize.y / 2f);
         centerPosition.offset(-(screenToCropSurfacePosition.x + cropSurfaceToWallpaperPosition.x),
                 -(screenToCropSurfacePosition.y + cropSurfaceToWallpaperPosition.y));

         mFullResImageView.setScaleAndCenter(minWallpaperZoom, centerPosition);
     }

     private Rect calculateCropRect() {
         // Calculate Rect of wallpaper in physical pixel terms (i.e., scaled to current zoom).
         float wallpaperZoom = mFullResImageView.getScale();
         int scaledWallpaperWidth = (int) (mRawWallpaperSize.x * wallpaperZoom);
         int scaledWallpaperHeight = (int) (mRawWallpaperSize.y * wallpaperZoom);
         Rect rect = new Rect();
         mFullResImageView.visibleFileRect(rect);
         int scrollX = (int) (rect.left * wallpaperZoom);
         int scrollY = (int) (rect.top * wallpaperZoom);

         rect.set(0, 0, scaledWallpaperWidth, scaledWallpaperHeight);

         Display defaultDisplay =  requireActivity().getWindowManager().getDefaultDisplay();
         Point screenSize = ScreenSizeCalculator.getInstance().getScreenSize(defaultDisplay);
         // Crop rect should start off as the visible screen and then include extra width and height
         // if available within wallpaper at the current zoom.
         Rect cropRect = new Rect(scrollX, scrollY, scrollX + screenSize.x, scrollY + screenSize.y);

         Point defaultCropSurfaceSize = WallpaperCropUtils.getDefaultCropSurfaceSize(
                 getResources(), defaultDisplay);
         int extraWidth = defaultCropSurfaceSize.x - screenSize.x;
         int extraHeightTopAndBottom = (int) ((defaultCropSurfaceSize.y - screenSize.y) / 2f);

         // Try to increase size of screenRect to include extra width depending on the layout
         // direction.
         if (isRtl()) {
             cropRect.left = Math.max(cropRect.left - extraWidth, rect.left);
         } else {
             cropRect.right = Math.min(cropRect.right + extraWidth, rect.right);
         }

         // Try to increase the size of the cropRect to to include extra height.
         int availableExtraHeightTop = cropRect.top - Math.max(
                 rect.top,
                 cropRect.top - extraHeightTopAndBottom);
         int availableExtraHeightBottom = Math.min(
                 rect.bottom,
                 cropRect.bottom + extraHeightTopAndBottom) - cropRect.bottom;

         int availableExtraHeightTopAndBottom =
                 Math.min(availableExtraHeightTop, availableExtraHeightBottom);
         cropRect.top -= availableExtraHeightTopAndBottom;
         cropRect.bottom += availableExtraHeightTopAndBottom;

         return cropRect;
     }

     @Override
     protected void setCurrentWallpaper(@Destination int destination) {
         mWallpaperSetter.setCurrentWallpaper(getActivity(), mWallpaper, mWallpaperAsset,
                 destination, mFullResImageView.getScale(), calculateCropRect(),
                 new SetWallpaperCallback() {
                     @Override
                     public void onSuccess() {
                         finishActivityWithResultOk();
                     }

                     @Override
                     public void onError(@Nullable Throwable throwable) {
                         showSetWallpaperErrorDialog(destination);
                     }
                 });
     }
 }
	/*
	* Copyright (C) 2019 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.android.wallpaper.picker;

	import android.animation.Animator;
	import android.animation.AnimatorListenerAdapter;
	import android.app.Activity;
	import android.content.Context;
	import android.graphics.Bitmap;
	import android.graphics.Bitmap.Config;
	import android.graphics.Color;
	import android.graphics.Point;
	import android.graphics.PointF;
	import android.graphics.Rect;
	import android.os.Bundle;
	import android.view.Display;
	import android.view.LayoutInflater;
	import android.view.View;
	import android.view.ViewGroup;
	import android.widget.ImageView;

	import androidx.annotation.Nullable;
	import androidx.fragment.app.FragmentActivity;

	import com.android.wallpaper.R;
	import com.android.wallpaper.asset.Asset;
	import com.android.wallpaper.module.WallpaperPersister.Destination;
	import com.android.wallpaper.module.WallpaperPersister.SetWallpaperCallback;
	import com.android.wallpaper.util.ScreenSizeCalculator;
	import com.android.wallpaper.util.WallpaperCropUtils;

	import com.bumptech.glide.Glide;
	import com.bumptech.glide.MemoryCategory;
	import com.davemorrissey.labs.subscaleview.ImageSource;
	import com.davemorrissey.labs.subscaleview.SubsamplingScaleImageView;
	import com.google.android.material.bottomsheet.BottomSheetBehavior;

	/**
	* Fragment which displays the UI for previewing an individual static wallpaper and its attribution
	* information.
	*/
	public class ImagePreviewFragment extends PreviewFragment {

	private static final float DEFAULT_WALLPAPER_MAX_ZOOM = 8f;

	private SubsamplingScaleImageView mFullResImageView;
	private Asset mWallpaperAsset;
	private Point mDefaultCropSurfaceSize;
	private Point mScreenSize;
	private Point mRawWallpaperSize; // Native size of wallpaper image.
	private ImageView mLowResImageView;

	private InfoPageController mInfoPageController;

	@Override
	public void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);
	mWallpaperAsset = mWallpaper.getAsset(requireContext().getApplicationContext());
	}

	@Override
	protected int getLayoutResId() {
	return R.layout.fragment_image_preview;
	}


	protected int getBottomSheetResId() {
	return R.id.bottom_sheet;
	}

	@Override
	protected int getLoadingIndicatorResId() {
	return R.id.loading_indicator;
	}

	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container,
	Bundle savedInstanceState) {
	View view = super.onCreateView(inflater, container, savedInstanceState);

	Activity activity = requireActivity();

	mFullResImageView = view.findViewById(R.id.full_res_image);

	mInfoPageController = new InfoPageController(view.findViewById(R.id.page_info),
	mPreviewMode);

	mLowResImageView = view.findViewById(R.id.low_res_image);

	// Trim some memory from Glide to make room for the full-size image in this fragment.
	Glide.get(activity).setMemoryCategory(MemoryCategory.LOW);

	mDefaultCropSurfaceSize = WallpaperCropUtils.getDefaultCropSurfaceSize(
	getResources(), activity.getWindowManager().getDefaultDisplay());
	mScreenSize = ScreenSizeCalculator.getInstance().getScreenSize(
	activity.getWindowManager().getDefaultDisplay());

	// Load a low-res placeholder image if there's a thumbnail available from the asset that can
	// be shown to the user more quickly than the full-sized image.
	if (mWallpaperAsset.hasLowResDataSource()) {
	mWallpaperAsset.loadLowResDrawable(activity, mLowResImageView, Color.BLACK,
	new WallpaperPreviewBitmapTransformation(activity.getApplicationContext(),
	isRtl()));
	}

	mWallpaperAsset.decodeRawDimensions(getActivity(), dimensions -> {
	// Don't continue loading the wallpaper if the Fragment is detached.
	if (getActivity() == null) {
	return;
	}

	// Return early and show a dialog if dimensions are null (signaling a decoding error).
	if (dimensions == null) {
	showLoadWallpaperErrorDialog();
	return;
	}

	mRawWallpaperSize = dimensions;
	setUpExploreIntent(ImagePreviewFragment.this::initFullResView);
	});

	setUpLoadingIndicator();

	return view;
	}

	@Override
	protected void setUpBottomSheetView(ViewGroup bottomSheet) {
	// Nothing needed here.
	}

	@Override
	protected boolean isLoaded() {
	return mFullResImageView != null && mFullResImageView.hasImage();
	}

	@Override
	public void onClickOk() {
	FragmentActivity activity = getActivity();
	if (activity != null) {
	activity.finish();
	}
	}

	@Override
	public void onDestroy() {
	super.onDestroy();
	if (mLoadingProgressBar != null) {
	mLoadingProgressBar.hide();
	}
	mFullResImageView.recycle();
	}

	@Override
	public void onSaveInstanceState(Bundle outState) {
	super.onSaveInstanceState(outState);

	final BottomSheetBehavior bottomSheetBehavior = BottomSheetBehavior.from(mBottomSheet);
	outState.putInt(KEY_BOTTOM_SHEET_STATE, bottomSheetBehavior.getState());
	}

	@Override
	protected void setBottomSheetContentAlpha(float alpha) {
	mInfoPageController.setContentAlpha(alpha);
	}

	@Override
	protected CharSequence getExploreButtonLabel(Context context) {
	return context.getString(mWallpaper.getActionLabelRes(context));
	}

	/**
	* Initializes MosaicView by initializing tiling, setting a fallback page bitmap, and
	* initializing a zoom-scroll observer and click listener.
	*/
	private void initFullResView() {
	mFullResImageView.setMinimumScaleType(SubsamplingScaleImageView.SCALE_TYPE_CENTER_CROP);

	// Set a solid black "page bitmap" so MosaicView draws a black background while waiting
	// for the image to load or a transparent one if a thumbnail already loaded.
	Bitmap blackBitmap = Bitmap.createBitmap(1, 1, Config.ARGB_8888);
	int color = (mLowResImageView.getDrawable() == null) ? Color.BLACK : Color.TRANSPARENT;
	blackBitmap.setPixel(0, 0, color);
	mFullResImageView.setImage(ImageSource.bitmap(blackBitmap));

	// Then set a fallback "page bitmap" to cover the whole MosaicView, which is an actual
	// (lower res) version of the image to be displayed.
	Point targetPageBitmapSize = new Point(mRawWallpaperSize);
	mWallpaperAsset.decodeBitmap(targetPageBitmapSize.x, targetPageBitmapSize.y,
	pageBitmap -> {
	// Check that the activity is still around since the decoding task started.
	if (getActivity() == null) {
	return;
	}

	// Some of these may be null depending on if the Fragment is paused, stopped,
	// or destroyed.
	if (mLoadingProgressBar != null) {
	mLoadingProgressBar.hide();
	}
	// The page bitmap may be null if there was a decoding error, so show an
	// error dialog.
	if (pageBitmap == null) {
	showLoadWallpaperErrorDialog();
	return;
	}
	if (mFullResImageView != null) {
	// Set page bitmap.
	mFullResImageView.setImage(ImageSource.bitmap(pageBitmap));

	setDefaultWallpaperZoomAndScroll();
	crossFadeInMosaicView();
	}
	getActivity().invalidateOptionsMenu();

	populateInfoPage(mInfoPageController);
	});
	}

	/**
	* Makes the MosaicView visible with an alpha fade-in animation while fading out the loading
	* indicator.
	*/
	private void crossFadeInMosaicView() {
	long shortAnimationDuration = getResources().getInteger(
	android.R.integer.config_shortAnimTime);

	mFullResImageView.setAlpha(0f);
	mFullResImageView.animate()
	.alpha(1f)
	.setDuration(shortAnimationDuration)
	.setListener(new AnimatorListenerAdapter() {
	@Override
	public void onAnimationEnd(Animator animation) {
	// Clear the thumbnail bitmap reference to save memory since it's no longer
	// visible.
	if (mLowResImageView != null) {
	mLowResImageView.setImageBitmap(null);
	}
	}
	});

	mLoadingProgressBar.animate()
	.alpha(0f)
	.setDuration(shortAnimationDuration)
	.setListener(new AnimatorListenerAdapter() {
	@Override
	public void onAnimationEnd(Animator animation) {
	if (mLoadingProgressBar != null) {
	mLoadingProgressBar.hide();
	}
	}
	});
	}

	/**
	* Sets the default wallpaper zoom and scroll position based on a "crop surface"
	* (with extra width to account for parallax) superimposed on the screen. Shows as much of the
	* wallpaper as possible on the crop surface and align screen to crop surface such that the
	* default preview matches what would be seen by the user in the left-most home screen.
	*
	* <p>This method is called once in the Fragment lifecycle after the wallpaper asset has loaded
	* and rendered to the layout.
	*/
	private void setDefaultWallpaperZoomAndScroll() {
	// Determine minimum zoom to fit maximum visible area of wallpaper on crop surface.
	float defaultWallpaperZoom =
	WallpaperCropUtils.calculateMinZoom(mRawWallpaperSize, mDefaultCropSurfaceSize);
	float minWallpaperZoom =
	WallpaperCropUtils.calculateMinZoom(mRawWallpaperSize, mScreenSize);

	Point screenToCropSurfacePosition = WallpaperCropUtils.calculateCenterPosition(
	mDefaultCropSurfaceSize, mScreenSize, true /* alignStart */, isRtl());
	Point zoomedWallpaperSize = new Point(
	Math.round(mRawWallpaperSize.x * defaultWallpaperZoom),
	Math.round(mRawWallpaperSize.y * defaultWallpaperZoom));
	Point cropSurfaceToWallpaperPosition = WallpaperCropUtils.calculateCenterPosition(
	zoomedWallpaperSize, mDefaultCropSurfaceSize, false /* alignStart */, isRtl());

	// Set min wallpaper zoom and max zoom on MosaicView widget.
	mFullResImageView.setMaxScale(Math.max(DEFAULT_WALLPAPER_MAX_ZOOM, defaultWallpaperZoom));
	mFullResImageView.setMinScale(minWallpaperZoom);

	// Set center to composite positioning between scaled wallpaper and screen.
	PointF centerPosition = new PointF(
	mRawWallpaperSize.x / 2f,
	mRawWallpaperSize.y / 2f);
	centerPosition.offset(-(screenToCropSurfacePosition.x + cropSurfaceToWallpaperPosition.x),
	-(screenToCropSurfacePosition.y + cropSurfaceToWallpaperPosition.y));

	mFullResImageView.setScaleAndCenter(minWallpaperZoom, centerPosition);
	}

	private Rect calculateCropRect() {
	// Calculate Rect of wallpaper in physical pixel terms (i.e., scaled to current zoom).
	float wallpaperZoom = mFullResImageView.getScale();
	int scaledWallpaperWidth = (int) (mRawWallpaperSize.x * wallpaperZoom);
	int scaledWallpaperHeight = (int) (mRawWallpaperSize.y * wallpaperZoom);
	Rect rect = new Rect();
	mFullResImageView.visibleFileRect(rect);
	int scrollX = (int) (rect.left * wallpaperZoom);
	int scrollY = (int) (rect.top * wallpaperZoom);

	rect.set(0, 0, scaledWallpaperWidth, scaledWallpaperHeight);

	Display defaultDisplay = requireActivity().getWindowManager().getDefaultDisplay();
	Point screenSize = ScreenSizeCalculator.getInstance().getScreenSize(defaultDisplay);
	// Crop rect should start off as the visible screen and then include extra width and height
	// if available within wallpaper at the current zoom.
	Rect cropRect = new Rect(scrollX, scrollY, scrollX + screenSize.x, scrollY + screenSize.y);

	Point defaultCropSurfaceSize = WallpaperCropUtils.getDefaultCropSurfaceSize(
	getResources(), defaultDisplay);
	int extraWidth = defaultCropSurfaceSize.x - screenSize.x;
	int extraHeightTopAndBottom = (int) ((defaultCropSurfaceSize.y - screenSize.y) / 2f);

	// Try to increase size of screenRect to include extra width depending on the layout
	// direction.
	if (isRtl()) {
	cropRect.left = Math.max(cropRect.left - extraWidth, rect.left);
	} else {
	cropRect.right = Math.min(cropRect.right + extraWidth, rect.right);
	}

	// Try to increase the size of the cropRect to to include extra height.
	int availableExtraHeightTop = cropRect.top - Math.max(
	rect.top,
	cropRect.top - extraHeightTopAndBottom);
	int availableExtraHeightBottom = Math.min(
	rect.bottom,
	cropRect.bottom + extraHeightTopAndBottom) - cropRect.bottom;

	int availableExtraHeightTopAndBottom =
	Math.min(availableExtraHeightTop, availableExtraHeightBottom);
	cropRect.top -= availableExtraHeightTopAndBottom;
	cropRect.bottom += availableExtraHeightTopAndBottom;

	return cropRect;
	}

	@Override
	protected void setCurrentWallpaper(@Destination int destination) {
	mWallpaperSetter.setCurrentWallpaper(getActivity(), mWallpaper, mWallpaperAsset,
	destination, mFullResImageView.getScale(), calculateCropRect(),
	new SetWallpaperCallback() {
	@Override
	public void onSuccess() {
	finishActivityWithResultOk();
	}

	@Override
	public void onError(@Nullable Throwable throwable) {
	showSetWallpaperErrorDialog(destination);
	}
	});
	}
	}