src/com/android/customization/picker/grid/GridFragment.java - platform/packages/apps/ThemePicker - Git at Google

 /*
  * Copyright (C) 2018 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.customization.picker.grid;

 import static com.android.wallpaper.widget.BottomActionBar.BottomAction.APPLY;

 import android.app.Activity;
 import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.drawable.BitmapDrawable;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Message;
 import android.os.RemoteException;
 import android.util.DisplayMetrics;
 import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.Surface;
 import android.view.SurfaceHolder;
 import android.view.SurfaceView;
 import android.view.View;
 import android.view.View.OnLayoutChangeListener;
 import android.view.ViewGroup;
 import android.widget.ImageView;
 import android.widget.Toast;

 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.cardview.widget.CardView;
 import androidx.core.widget.ContentLoadingProgressBar;
 import androidx.recyclerview.widget.RecyclerView;

 import com.android.customization.model.CustomizationManager.Callback;
 import com.android.customization.model.CustomizationManager.OptionsFetchedListener;
 import com.android.customization.model.grid.GridOption;
 import com.android.customization.model.grid.GridOptionsManager;
 import com.android.customization.module.ThemesUserEventLogger;
 import com.android.customization.picker.BasePreviewAdapter;
 import com.android.customization.picker.BasePreviewAdapter.PreviewPage;
 import com.android.customization.widget.OptionSelectorController;
 import com.android.wallpaper.R;
 import com.android.wallpaper.asset.Asset;
 import com.android.wallpaper.asset.ContentUriAsset;
 import com.android.wallpaper.model.WallpaperInfo;
 import com.android.wallpaper.module.CurrentWallpaperInfoFactory;
 import com.android.wallpaper.module.InjectorProvider;
 import com.android.wallpaper.picker.AppbarFragment;
 import com.android.wallpaper.util.SurfaceViewUtils;
 import com.android.wallpaper.widget.BottomActionBar;
 import com.android.wallpaper.widget.PreviewPager;

 import com.bumptech.glide.Glide;
 import com.bumptech.glide.request.RequestOptions;

 import java.util.List;

 /**
  * Fragment that contains the UI for selecting and applying a GridOption.
  */
 public class GridFragment extends AppbarFragment {

     private static final int PREVIEW_FADE_DURATION_MS = 100;

     private static final String TAG = "GridFragment";

     /**
      * Interface to be implemented by an Activity hosting a {@link GridFragment}
      */
     public interface GridFragmentHost {
         GridOptionsManager getGridOptionsManager();
     }

     public static GridFragment newInstance(CharSequence title) {
         GridFragment fragment = new GridFragment();
         fragment.setArguments(AppbarFragment.createArguments(title));
         return fragment;
     }

     private WallpaperInfo mHomeWallpaper;
     private float mScreenAspectRatio;
     private int mCardHeight;
     private int mCardWidth;
     private BitmapDrawable mCardBackground;
     private GridPreviewAdapter mAdapter;
     private RecyclerView mOptionsContainer;
     private OptionSelectorController<GridOption> mOptionsController;
     private GridOptionsManager mGridManager;
     private GridOption mSelectedOption;
     private PreviewPager mPreviewPager;
     private ContentLoadingProgressBar mLoading;
     private View mContent;
     private View mError;
     private BottomActionBar mBottomActionBar;
     private ThemesUserEventLogger mEventLogger;
     private boolean mReloadOptionsAfterApplying;

     private final Callback mApplyGridCallback = new Callback() {
         @Override
         public void onSuccess() {
             mGridManager.fetchOptions(new OptionsFetchedListener<GridOption>() {
                 @Override
                 public void onOptionsLoaded(List<GridOption> options) {
                     mOptionsController.resetOptions(options);
                     mSelectedOption = getSelectedOption(options);
                     mReloadOptionsAfterApplying = true;
                     // It will trigger OptionSelectedListener#onOptionSelected.
                     mOptionsController.setSelectedOption(mSelectedOption);
                     Toast.makeText(getContext(), R.string.applied_grid_msg, Toast.LENGTH_SHORT)
                             .show();
                     // Since we disabled it when clicked apply button.
                     mBottomActionBar.enableActions();
                     mBottomActionBar.hide();
                 }

                 @Override
                 public void onError(@Nullable Throwable throwable) {
                     if (throwable != null) {
                         Log.e(TAG, "Error loading grid options", throwable);
                     }
                     showError();
                 }
             }, true);
         }

         @Override
         public void onError(@Nullable Throwable throwable) {
             //TODO(chihhangchuang): handle
         }
     };

     @Override
     public void onAttach(Context context) {
         super.onAttach(context);
         mGridManager = ((GridFragmentHost) context).getGridOptionsManager();
         mEventLogger = (ThemesUserEventLogger)
                 InjectorProvider.getInjector().getUserEventLogger(context);
     }

     @Nullable
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container,
             @Nullable Bundle savedInstanceState) {
         View view = inflater.inflate(
                 R.layout.fragment_grid_picker, container, /* attachToRoot */ false);
         setUpToolbar(view);
         mContent = view.findViewById(R.id.content_section);
         mPreviewPager = view.findViewById(R.id.grid_preview_pager);
         mOptionsContainer = view.findViewById(R.id.options_container);
         mLoading = view.findViewById(R.id.loading_indicator);
         mError = view.findViewById(R.id.error_section);
         final Resources res = getResources();
         DisplayMetrics dm = res.getDisplayMetrics();
         mScreenAspectRatio = (float) dm.heightPixels / dm.widthPixels;

         // Clear memory cache whenever grid fragment view is being loaded.
         Glide.get(getContext()).clearMemory();
         setUpOptions();

         CurrentWallpaperInfoFactory factory = InjectorProvider.getInjector()
                 .getCurrentWallpaperFactory(getContext().getApplicationContext());

         factory.createCurrentWallpaperInfos((homeWallpaper, lockWallpaper, presentationMode) -> {
             mHomeWallpaper = homeWallpaper;
             loadWallpaperBackground();

         }, false);
         view.addOnLayoutChangeListener(new OnLayoutChangeListener() {
             @Override
             public void onLayoutChange(View v, int left, int top, int right, int bottom,
                     int oldLeft, int oldTop, int oldRight, int oldBottom) {
                 mCardHeight = mPreviewPager.getHeight() - mPreviewPager.getPaddingTop() -
                         res.getDimensionPixelSize(R.dimen.indicator_container_height);
                 mCardWidth = (int) (mCardHeight / mScreenAspectRatio);
                 view.removeOnLayoutChangeListener(this);
                 loadWallpaperBackground();
             }
         });
         return view;
     }

     @Override
     protected void onBottomActionBarReady(BottomActionBar bottomActionBar) {
         mBottomActionBar = bottomActionBar;
         mBottomActionBar.showActionsOnly(APPLY);
         mBottomActionBar.setActionClickListener(APPLY, unused -> {
             mBottomActionBar.disableActions();
             mGridManager.apply(mSelectedOption, mApplyGridCallback);
         });
     }

     private void loadWallpaperBackground() {
         if (mHomeWallpaper != null && mCardHeight > 0 && mCardWidth > 0) {
             mHomeWallpaper.getThumbAsset(getContext()).decodeBitmap(mCardWidth,
                     mCardHeight,
                     bitmap -> {
                         mCardBackground =
                                 new BitmapDrawable(getResources(), bitmap);
                         if (mAdapter != null) {
                             mAdapter.onWallpaperInfoLoaded();
                         }
                     });
         }
     }

     private void createAdapter() {
         mAdapter = new GridPreviewAdapter(mSelectedOption);
         mPreviewPager.setAdapter(mAdapter);
     }

     private void setUpOptions() {
         hideError();
         mLoading.show();
         mGridManager.fetchOptions(new OptionsFetchedListener<GridOption>() {
             @Override
             public void onOptionsLoaded(List<GridOption> options) {
                 mLoading.hide();
                 mOptionsController = new OptionSelectorController<>(mOptionsContainer, options);

                 mOptionsController.addListener(selected -> {
                     mSelectedOption = (GridOption) selected;
                     if (mReloadOptionsAfterApplying) {
                         mReloadOptionsAfterApplying = false;
                         return;
                     }
                     mBottomActionBar.show();
                     mEventLogger.logGridSelected(mSelectedOption);
                     createAdapter();
                 });
                 mOptionsController.initOptions(mGridManager);
                 mSelectedOption = getSelectedOption(options);
                 createAdapter();
             }

             @Override
             public void onError(@Nullable Throwable throwable) {
                 if (throwable != null) {
                     Log.e(TAG, "Error loading grid options", throwable);
                 }
                 showError();
             }
         }, false);
     }

     private GridOption getSelectedOption(List<GridOption> options) {
         return options.stream()
                 .filter(option -> option.isActive(mGridManager))
                 .findAny()
                 // For development only, as there should always be a grid set.
                 .orElse(options.get(0));
     }

     private void hideError() {
         mContent.setVisibility(View.VISIBLE);
         mError.setVisibility(View.GONE);
     }

     private void showError() {
         mLoading.hide();
         mContent.setVisibility(View.GONE);
         mError.setVisibility(View.VISIBLE);
     }

     private class GridPreviewPage extends PreviewPage {
         private final int mPageId;
         private final Asset mPreviewAsset;
         private final int mCols;
         private final int mRows;
         private final Activity mActivity;

         private final String mName;

         private ImageView mPreview;
         private SurfaceView mPreviewSurface;

         private final SurfaceHolder.Callback mSurfaceCallback = new SurfaceHolder.Callback() {

             private Surface mLastSurface;
             private Message mCallback;

             @Override
             public void surfaceCreated(SurfaceHolder holder) {
                 if (mLastSurface != holder.getSurface()) {
                     mLastSurface = holder.getSurface();
                     Bundle result = mGridManager.renderPreview(
                             SurfaceViewUtils.createSurfaceViewRequest(mPreviewSurface), mName);
                     if (result != null) {
                         mPreviewSurface.setChildSurfacePackage(
                                 SurfaceViewUtils.getSurfacePackage(result));
                         mCallback = SurfaceViewUtils.getCallback(result);
                     }
                 }
             }

             @Override
             public void surfaceChanged(SurfaceHolder holder, int format, int width,
                     int height) {}

             @Override
             public void surfaceDestroyed(SurfaceHolder holder) {
                 if (mCallback != null) {
                     try {
                         mCallback.replyTo.send(mCallback);
                     } catch (RemoteException e) {
                         e.printStackTrace();
                     } finally {
                         mCallback = null;
                     }
                 }
             }
         };

         private GridPreviewPage(Activity activity, int id, Uri previewUri, String name, int rows,
                 int cols) {
             super(null);
             mPageId = id;
             mPreviewAsset = new ContentUriAsset(activity, previewUri,
                     RequestOptions.fitCenterTransform());
             mName = name;
             mRows = rows;
             mCols = cols;
             mActivity = activity;
         }

         @Override
         public void setCard(CardView card) {
             super.setCard(card);
             mPreview = card.findViewById(R.id.grid_preview_image);
             mPreviewSurface = card.findViewById(R.id.grid_preview_surface);
         }

         public void bindPreviewContent() {
             Resources resources = card.getResources();
             bindWallpaperIfAvailable();
             final boolean usesSurfaceViewForPreview = mGridManager.usesSurfaceView();
             mPreview.setVisibility(usesSurfaceViewForPreview ? View.GONE : View.VISIBLE);
             mPreviewSurface.setVisibility(usesSurfaceViewForPreview ? View.VISIBLE : View.GONE);
             if (usesSurfaceViewForPreview) {
                 mPreviewSurface.setZOrderOnTop(true);
                 mPreviewSurface.getHolder().addCallback(mSurfaceCallback);
             } else {
                 mPreviewAsset.loadDrawableWithTransition(mActivity,
                         mPreview /* imageView */,
                         PREVIEW_FADE_DURATION_MS /* duration */,
                         null /* drawableLoadedListener */,
                         resources.getColor(android.R.color.transparent,
                                 null) /* placeHolderColorJ */);
             }
         }

         void bindWallpaperIfAvailable() {
             if (card != null && mCardBackground != null) {
                 mPreview.setBackground(mCardBackground);
                 mPreviewSurface.setBackground(mCardBackground);
             }
         }
     }
     /**
      * Adapter class for mPreviewPager.
      * This is a ViewPager as it allows for a nice pagination effect (ie, pages snap on swipe,
      * we don't want to just scroll)
      */
     class GridPreviewAdapter extends BasePreviewAdapter<GridPreviewPage> {

         GridPreviewAdapter(GridOption gridOption) {
             super(getContext(), R.layout.grid_preview_card);
             for (int i = 0; i < gridOption.previewPagesCount; i++) {
                 addPage(new GridPreviewPage(getActivity(), i,
                         gridOption.previewImageUri.buildUpon().appendPath("" + i).build(),
                         gridOption.name, gridOption.rows, gridOption.cols));
             }
         }

         void onWallpaperInfoLoaded() {
             for (GridPreviewPage page : mPages) {
                 page.bindWallpaperIfAvailable();
             }
         }
     }
 }
	/*
	* Copyright (C) 2018 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.customization.picker.grid;

	import static com.android.wallpaper.widget.BottomActionBar.BottomAction.APPLY;

	import android.app.Activity;
	import android.content.Context;
	import android.content.res.Resources;
	import android.graphics.drawable.BitmapDrawable;
	import android.net.Uri;
	import android.os.Bundle;
	import android.os.Message;
	import android.os.RemoteException;
	import android.util.DisplayMetrics;
	import android.util.Log;
	import android.view.LayoutInflater;
	import android.view.Surface;
	import android.view.SurfaceHolder;
	import android.view.SurfaceView;
	import android.view.View;
	import android.view.View.OnLayoutChangeListener;
	import android.view.ViewGroup;
	import android.widget.ImageView;
	import android.widget.Toast;

	import androidx.annotation.NonNull;
	import androidx.annotation.Nullable;
	import androidx.cardview.widget.CardView;
	import androidx.core.widget.ContentLoadingProgressBar;
	import androidx.recyclerview.widget.RecyclerView;

	import com.android.customization.model.CustomizationManager.Callback;
	import com.android.customization.model.CustomizationManager.OptionsFetchedListener;
	import com.android.customization.model.grid.GridOption;
	import com.android.customization.model.grid.GridOptionsManager;
	import com.android.customization.module.ThemesUserEventLogger;
	import com.android.customization.picker.BasePreviewAdapter;
	import com.android.customization.picker.BasePreviewAdapter.PreviewPage;
	import com.android.customization.widget.OptionSelectorController;
	import com.android.wallpaper.R;
	import com.android.wallpaper.asset.Asset;
	import com.android.wallpaper.asset.ContentUriAsset;
	import com.android.wallpaper.model.WallpaperInfo;
	import com.android.wallpaper.module.CurrentWallpaperInfoFactory;
	import com.android.wallpaper.module.InjectorProvider;
	import com.android.wallpaper.picker.AppbarFragment;
	import com.android.wallpaper.util.SurfaceViewUtils;
	import com.android.wallpaper.widget.BottomActionBar;
	import com.android.wallpaper.widget.PreviewPager;

	import com.bumptech.glide.Glide;
	import com.bumptech.glide.request.RequestOptions;

	import java.util.List;

	/**
	* Fragment that contains the UI for selecting and applying a GridOption.
	*/
	public class GridFragment extends AppbarFragment {

	private static final int PREVIEW_FADE_DURATION_MS = 100;

	private static final String TAG = "GridFragment";

	/**
	* Interface to be implemented by an Activity hosting a {@link GridFragment}
	*/
	public interface GridFragmentHost {
	GridOptionsManager getGridOptionsManager();
	}

	public static GridFragment newInstance(CharSequence title) {
	GridFragment fragment = new GridFragment();
	fragment.setArguments(AppbarFragment.createArguments(title));
	return fragment;
	}

	private WallpaperInfo mHomeWallpaper;
	private float mScreenAspectRatio;
	private int mCardHeight;
	private int mCardWidth;
	private BitmapDrawable mCardBackground;
	private GridPreviewAdapter mAdapter;
	private RecyclerView mOptionsContainer;
	private OptionSelectorController<GridOption> mOptionsController;
	private GridOptionsManager mGridManager;
	private GridOption mSelectedOption;
	private PreviewPager mPreviewPager;
	private ContentLoadingProgressBar mLoading;
	private View mContent;
	private View mError;
	private BottomActionBar mBottomActionBar;
	private ThemesUserEventLogger mEventLogger;
	private boolean mReloadOptionsAfterApplying;

	private final Callback mApplyGridCallback = new Callback() {
	@Override
	public void onSuccess() {
	mGridManager.fetchOptions(new OptionsFetchedListener<GridOption>() {
	@Override
	public void onOptionsLoaded(List<GridOption> options) {
	mOptionsController.resetOptions(options);
	mSelectedOption = getSelectedOption(options);
	mReloadOptionsAfterApplying = true;
	// It will trigger OptionSelectedListener#onOptionSelected.
	mOptionsController.setSelectedOption(mSelectedOption);
	Toast.makeText(getContext(), R.string.applied_grid_msg, Toast.LENGTH_SHORT)
	.show();
	// Since we disabled it when clicked apply button.
	mBottomActionBar.enableActions();
	mBottomActionBar.hide();
	}

	@Override
	public void onError(@Nullable Throwable throwable) {
	if (throwable != null) {
	Log.e(TAG, "Error loading grid options", throwable);
	}
	showError();
	}
	}, true);
	}

	@Override
	public void onError(@Nullable Throwable throwable) {
	//TODO(chihhangchuang): handle
	}
	};

	@Override
	public void onAttach(Context context) {
	super.onAttach(context);
	mGridManager = ((GridFragmentHost) context).getGridOptionsManager();
	mEventLogger = (ThemesUserEventLogger)
	InjectorProvider.getInjector().getUserEventLogger(context);
	}

	@Nullable
	@Override
	public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container,
	@Nullable Bundle savedInstanceState) {
	View view = inflater.inflate(
	R.layout.fragment_grid_picker, container, /* attachToRoot */ false);
	setUpToolbar(view);
	mContent = view.findViewById(R.id.content_section);
	mPreviewPager = view.findViewById(R.id.grid_preview_pager);
	mOptionsContainer = view.findViewById(R.id.options_container);
	mLoading = view.findViewById(R.id.loading_indicator);
	mError = view.findViewById(R.id.error_section);
	final Resources res = getResources();
	DisplayMetrics dm = res.getDisplayMetrics();
	mScreenAspectRatio = (float) dm.heightPixels / dm.widthPixels;

	// Clear memory cache whenever grid fragment view is being loaded.
	Glide.get(getContext()).clearMemory();
	setUpOptions();

	CurrentWallpaperInfoFactory factory = InjectorProvider.getInjector()
	.getCurrentWallpaperFactory(getContext().getApplicationContext());

	factory.createCurrentWallpaperInfos((homeWallpaper, lockWallpaper, presentationMode) -> {
	mHomeWallpaper = homeWallpaper;
	loadWallpaperBackground();

	}, false);
	view.addOnLayoutChangeListener(new OnLayoutChangeListener() {
	@Override
	public void onLayoutChange(View v, int left, int top, int right, int bottom,
	int oldLeft, int oldTop, int oldRight, int oldBottom) {
	mCardHeight = mPreviewPager.getHeight() - mPreviewPager.getPaddingTop() -
	res.getDimensionPixelSize(R.dimen.indicator_container_height);
	mCardWidth = (int) (mCardHeight / mScreenAspectRatio);
	view.removeOnLayoutChangeListener(this);
	loadWallpaperBackground();
	}
	});
	return view;
	}

	@Override
	protected void onBottomActionBarReady(BottomActionBar bottomActionBar) {
	mBottomActionBar = bottomActionBar;
	mBottomActionBar.showActionsOnly(APPLY);
	mBottomActionBar.setActionClickListener(APPLY, unused -> {
	mBottomActionBar.disableActions();
	mGridManager.apply(mSelectedOption, mApplyGridCallback);
	});
	}

	private void loadWallpaperBackground() {
	if (mHomeWallpaper != null && mCardHeight > 0 && mCardWidth > 0) {
	mHomeWallpaper.getThumbAsset(getContext()).decodeBitmap(mCardWidth,
	mCardHeight,
	bitmap -> {
	mCardBackground =
	new BitmapDrawable(getResources(), bitmap);
	if (mAdapter != null) {
	mAdapter.onWallpaperInfoLoaded();
	}
	});
	}
	}

	private void createAdapter() {
	mAdapter = new GridPreviewAdapter(mSelectedOption);
	mPreviewPager.setAdapter(mAdapter);
	}

	private void setUpOptions() {
	hideError();
	mLoading.show();
	mGridManager.fetchOptions(new OptionsFetchedListener<GridOption>() {
	@Override
	public void onOptionsLoaded(List<GridOption> options) {
	mLoading.hide();
	mOptionsController = new OptionSelectorController<>(mOptionsContainer, options);

	mOptionsController.addListener(selected -> {
	mSelectedOption = (GridOption) selected;
	if (mReloadOptionsAfterApplying) {
	mReloadOptionsAfterApplying = false;
	return;
	}
	mBottomActionBar.show();
	mEventLogger.logGridSelected(mSelectedOption);
	createAdapter();
	});
	mOptionsController.initOptions(mGridManager);
	mSelectedOption = getSelectedOption(options);
	createAdapter();
	}

	@Override
	public void onError(@Nullable Throwable throwable) {
	if (throwable != null) {
	Log.e(TAG, "Error loading grid options", throwable);
	}
	showError();
	}
	}, false);
	}

	private GridOption getSelectedOption(List<GridOption> options) {
	return options.stream()
	.filter(option -> option.isActive(mGridManager))
	.findAny()
	// For development only, as there should always be a grid set.
	.orElse(options.get(0));
	}

	private void hideError() {
	mContent.setVisibility(View.VISIBLE);
	mError.setVisibility(View.GONE);
	}

	private void showError() {
	mLoading.hide();
	mContent.setVisibility(View.GONE);
	mError.setVisibility(View.VISIBLE);
	}

	private class GridPreviewPage extends PreviewPage {
	private final int mPageId;
	private final Asset mPreviewAsset;
	private final int mCols;
	private final int mRows;
	private final Activity mActivity;

	private final String mName;

	private ImageView mPreview;
	private SurfaceView mPreviewSurface;

	private final SurfaceHolder.Callback mSurfaceCallback = new SurfaceHolder.Callback() {

	private Surface mLastSurface;
	private Message mCallback;

	@Override
	public void surfaceCreated(SurfaceHolder holder) {
	if (mLastSurface != holder.getSurface()) {
	mLastSurface = holder.getSurface();
	Bundle result = mGridManager.renderPreview(
	SurfaceViewUtils.createSurfaceViewRequest(mPreviewSurface), mName);
	if (result != null) {
	mPreviewSurface.setChildSurfacePackage(
	SurfaceViewUtils.getSurfacePackage(result));
	mCallback = SurfaceViewUtils.getCallback(result);
	}
	}
	}

	@Override
	public void surfaceChanged(SurfaceHolder holder, int format, int width,
	int height) {}

	@Override
	public void surfaceDestroyed(SurfaceHolder holder) {
	if (mCallback != null) {
	try {
	mCallback.replyTo.send(mCallback);
	} catch (RemoteException e) {
	e.printStackTrace();
	} finally {
	mCallback = null;
	}
	}
	}
	};

	private GridPreviewPage(Activity activity, int id, Uri previewUri, String name, int rows,
	int cols) {
	super(null);
	mPageId = id;
	mPreviewAsset = new ContentUriAsset(activity, previewUri,
	RequestOptions.fitCenterTransform());
	mName = name;
	mRows = rows;
	mCols = cols;
	mActivity = activity;
	}

	@Override
	public void setCard(CardView card) {
	super.setCard(card);
	mPreview = card.findViewById(R.id.grid_preview_image);
	mPreviewSurface = card.findViewById(R.id.grid_preview_surface);
	}

	public void bindPreviewContent() {
	Resources resources = card.getResources();
	bindWallpaperIfAvailable();
	final boolean usesSurfaceViewForPreview = mGridManager.usesSurfaceView();
	mPreview.setVisibility(usesSurfaceViewForPreview ? View.GONE : View.VISIBLE);
	mPreviewSurface.setVisibility(usesSurfaceViewForPreview ? View.VISIBLE : View.GONE);
	if (usesSurfaceViewForPreview) {
	mPreviewSurface.setZOrderOnTop(true);
	mPreviewSurface.getHolder().addCallback(mSurfaceCallback);
	} else {
	mPreviewAsset.loadDrawableWithTransition(mActivity,
	mPreview /* imageView */,
	PREVIEW_FADE_DURATION_MS /* duration */,
	null /* drawableLoadedListener */,
	resources.getColor(android.R.color.transparent,
	null) /* placeHolderColorJ */);
	}
	}

	void bindWallpaperIfAvailable() {
	if (card != null && mCardBackground != null) {
	mPreview.setBackground(mCardBackground);
	mPreviewSurface.setBackground(mCardBackground);
	}
	}
	}
	/**
	* Adapter class for mPreviewPager.
	* This is a ViewPager as it allows for a nice pagination effect (ie, pages snap on swipe,
	* we don't want to just scroll)
	*/
	class GridPreviewAdapter extends BasePreviewAdapter<GridPreviewPage> {

	GridPreviewAdapter(GridOption gridOption) {
	super(getContext(), R.layout.grid_preview_card);
	for (int i = 0; i < gridOption.previewPagesCount; i++) {
	addPage(new GridPreviewPage(getActivity(), i,
	gridOption.previewImageUri.buildUpon().appendPath("" + i).build(),
	gridOption.name, gridOption.rows, gridOption.cols));
	}
	}

	void onWallpaperInfoLoaded() {
	for (GridPreviewPage page : mPages) {
	page.bindWallpaperIfAvailable();
	}
	}
	}
	}