src/com/android/documentsui/dirlist/IconHelper.java - platform/packages/apps/DocumentsUI - Gitiles

 /*
  * Copyright (C) 2015 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.documentsui.dirlist;

 import static com.android.documentsui.base.Shared.VERBOSE;
 import static com.android.documentsui.base.State.MODE_GRID;
 import static com.android.documentsui.base.State.MODE_LIST;

 import android.content.ContentProviderClient;
 import android.content.ContentResolver;
 import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.Point;
 import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.os.AsyncTask;
 import android.os.CancellationSignal;
 import android.os.OperationCanceledException;
 import android.provider.DocumentsContract;
 import android.provider.DocumentsContract.Document;
 import android.support.annotation.Nullable;
 import android.util.Log;
 import android.view.View;
 import android.widget.ImageView;

 import com.android.documentsui.DocumentsApplication;
 import com.android.documentsui.IconUtils;
 import com.android.documentsui.ProviderExecutor;
 import com.android.documentsui.ProviderExecutor.Preemptable;
 import com.android.documentsui.R;
 import com.android.documentsui.ThumbnailCache;
 import com.android.documentsui.ThumbnailCache.Result;
 import com.android.documentsui.base.DocumentInfo;
 import com.android.documentsui.base.MimeTypes;
 import com.android.documentsui.base.State;
 import com.android.documentsui.base.State.ViewMode;

 import java.util.function.BiConsumer;

 /**
  * A class to assist with loading and managing the Images (i.e. thumbnails and icons) associated
  * with items in the directory listing.
  */
 public class IconHelper {
     private static final String TAG = "IconHelper";

     // Two animations applied to image views. The first is used to switch mime icon and thumbnail.
     // The second is used when we need to update thumbnail.
     private static final BiConsumer<View, View> ANIM_FADE_IN = (mime, thumb) -> {
         float alpha = mime.getAlpha();
         mime.animate().alpha(0f).start();
         thumb.setAlpha(0f);
         thumb.animate().alpha(alpha).start();
     };
     private static final BiConsumer<View, View> ANIM_NO_OP = (mime, thumb) -> {};

     private final Context mContext;
     private final ThumbnailCache mThumbnailCache;

     // The display mode (MODE_GRID, MODE_LIST, etc).
     private int mMode;
     private Point mCurrentSize;
     private boolean mThumbnailsEnabled = true;

     /**
      * @param context
      * @param mode MODE_GRID or MODE_LIST
      */
     public IconHelper(Context context, int mode) {
         mContext = context;
         setViewMode(mode);
         mThumbnailCache = DocumentsApplication.getThumbnailCache(context);
     }

     /**
      * Enables or disables thumbnails. When thumbnails are disabled, mime icons (or custom icons, if
      * specified by the document) are used instead.
      *
      * @param enabled
      */
     public void setThumbnailsEnabled(boolean enabled) {
         mThumbnailsEnabled = enabled;
     }

     /**
      * Sets the current display mode. This affects the thumbnail sizes that are loaded.
      *
      * @param mode See {@link State.MODE_LIST} and {@link State.MODE_GRID}.
      */
     public void setViewMode(@ViewMode int mode) {
         mMode = mode;
         int thumbSize = getThumbSize(mode);
         mCurrentSize = new Point(thumbSize, thumbSize);
     }

     private int getThumbSize(int mode) {
         int thumbSize;
         switch (mode) {
             case MODE_GRID:
                 thumbSize = mContext.getResources().getDimensionPixelSize(R.dimen.grid_width);
                 break;
             case MODE_LIST:
                 thumbSize = mContext.getResources().getDimensionPixelSize(
                         R.dimen.list_item_thumbnail_size);
                 break;
             default:
                 throw new IllegalArgumentException("Unsupported layout mode: " + mode);
         }
         return thumbSize;
     }

     /**
      * Cancels any ongoing load operations associated with the given ImageView.
      *
      * @param icon
      */
     public void stopLoading(ImageView icon) {
         final LoaderTask oldTask = (LoaderTask) icon.getTag();
         if (oldTask != null) {
             oldTask.preempt();
             icon.setTag(null);
         }
     }

     /** Internal task for loading thumbnails asynchronously. */
     private static class LoaderTask
             extends AsyncTask<Uri, Void, Bitmap>
             implements Preemptable {
         private final Uri mUri;
         private final ImageView mIconMime;
         private final ImageView mIconThumb;
         private final Point mThumbSize;
         private final long mLastModified;

         // A callback to apply animation to image views after the thumbnail is loaded.
         private final BiConsumer<View, View> mImageAnimator;

         private final CancellationSignal mSignal;

         public LoaderTask(Uri uri, ImageView iconMime, ImageView iconThumb,
                 Point thumbSize, long lastModified, BiConsumer<View, View> animator) {
             mUri = uri;
             mIconMime = iconMime;
             mIconThumb = iconThumb;
             mThumbSize = thumbSize;
             mImageAnimator = animator;
             mLastModified = lastModified;
             mSignal = new CancellationSignal();
             if (VERBOSE) Log.v(TAG, "Starting icon loader task for " + mUri);
         }

         @Override
         public void preempt() {
             if (VERBOSE) Log.v(TAG, "Icon loader task for " + mUri + " was cancelled.");
             cancel(false);
             mSignal.cancel();
         }

         @Override
         protected Bitmap doInBackground(Uri... params) {
             if (isCancelled()) {
                 return null;
             }

             final Context context = mIconThumb.getContext();
             final ContentResolver resolver = context.getContentResolver();

             ContentProviderClient client = null;
             Bitmap result = null;
             try {
                 client = DocumentsApplication.acquireUnstableProviderOrThrow(
                         resolver, mUri.getAuthority());
                 result = DocumentsContract.getDocumentThumbnail(client, mUri, mThumbSize, mSignal);
                 if (result != null) {
                     final ThumbnailCache cache = DocumentsApplication.getThumbnailCache(context);
                     cache.putThumbnail(mUri, mThumbSize, result, mLastModified);
                 }
             } catch (Exception e) {
                 if (!(e instanceof OperationCanceledException)) {
                     Log.w(TAG, "Failed to load thumbnail for " + mUri + ": " + e);
                 }
             } finally {
                 ContentProviderClient.releaseQuietly(client);
             }
             return result;
         }

         @Override
         protected void onPostExecute(Bitmap result) {
             if (VERBOSE) Log.v(TAG, "Loader task for " + mUri + " completed");

             if (mIconThumb.getTag() == this && result != null) {
                 mIconThumb.setTag(null);
                 mIconThumb.setImageBitmap(result);

                 mImageAnimator.accept(mIconMime, mIconThumb);
             }
         }
     }

     /**
      * Load thumbnails for a directory list item.
      *
      * @param doc The document
      * @param iconThumb The itemview's thumbnail icon.
      * @param iconMime The itemview's mime icon. Hidden when iconThumb is shown.
      * @param subIconMime The second itemview's mime icon. Always visible.
      * @return
      */
     public void load(
             DocumentInfo doc,
             ImageView iconThumb,
             ImageView iconMime,
             @Nullable ImageView subIconMime) {
         load(doc.derivedUri, doc.mimeType, doc.flags, doc.icon, doc.lastModified,
                 iconThumb, iconMime, subIconMime);
     }

     /**
      * Load thumbnails for a directory list item.
      *
      * @param uri The URI for the file being represented.
      * @param mimeType The mime type of the file being represented.
      * @param docFlags Flags for the file being represented.
      * @param docIcon Custom icon (if any) for the file being requested.
      * @param docLastModified the last modified value of the file being requested.
      * @param iconThumb The itemview's thumbnail icon.
      * @param iconMime The itemview's mime icon. Hidden when iconThumb is shown.
      * @param subIconMime The second itemview's mime icon. Always visible.
      * @return
      */
     public void load(Uri uri, String mimeType, int docFlags, int docIcon, long docLastModified,
             ImageView iconThumb, ImageView iconMime, @Nullable ImageView subIconMime) {
         boolean loadedThumbnail = false;

         final String docAuthority = uri.getAuthority();

         final boolean supportsThumbnail = (docFlags & Document.FLAG_SUPPORTS_THUMBNAIL) != 0;
         final boolean allowThumbnail = (mMode == MODE_GRID)
                 || MimeTypes.mimeMatches(MimeTypes.VISUAL_MIMES, mimeType);
         final boolean showThumbnail = supportsThumbnail && allowThumbnail && mThumbnailsEnabled;
         if (showThumbnail) {
             loadedThumbnail =
                 loadThumbnail(uri, docAuthority, docLastModified, iconThumb, iconMime);
         }

         final Drawable mimeIcon = getDocumentIcon(mContext, docAuthority,
                 DocumentsContract.getDocumentId(uri), mimeType, docIcon);
         if (subIconMime != null) {
             setMimeIcon(subIconMime, mimeIcon);
         }

         if (loadedThumbnail) {
             hideImageView(iconMime);
         } else {
             // Add a mime icon if the thumbnail is not shown.
             setMimeIcon(iconMime, mimeIcon);
             hideImageView(iconThumb);
         }
     }

     private boolean loadThumbnail(Uri uri, String docAuthority, long docLastModified,
             ImageView iconThumb, ImageView iconMime) {
         final Result result = mThumbnailCache.getThumbnail(uri, mCurrentSize);

         try {
             final Bitmap cachedThumbnail = result.getThumbnail();
             iconThumb.setImageBitmap(cachedThumbnail);

             boolean stale = (docLastModified > result.getLastModified());
             if (VERBOSE) Log.v(TAG,
                     String.format("Load thumbnail for %s, got result %d and stale %b.",
                             uri.toString(), result.getStatus(), stale));
             if (!result.isExactHit() || stale) {
                 final BiConsumer<View, View> animator =
                         (cachedThumbnail == null ? ANIM_FADE_IN : ANIM_NO_OP);
                 final LoaderTask task = new LoaderTask(uri, iconMime, iconThumb, mCurrentSize,
                         docLastModified, animator);

                 iconThumb.setTag(task);

                 ProviderExecutor.forAuthority(docAuthority).execute(task);
             }

             return result.isHit();
         } finally {
             result.recycle();
         }
     }

     private void setMimeIcon(ImageView view, Drawable icon) {
         view.setImageDrawable(icon);
         view.setAlpha(1f);
     }

     private void hideImageView(ImageView view) {
         view.setImageDrawable(null);
         view.setAlpha(0f);
     }

     private Drawable getDocumentIcon(
         Context context, String authority, String id, String mimeType, int icon) {
         if (icon != 0) {
             return IconUtils.loadPackageIcon(context, authority, icon);
         } else {
             return IconUtils.loadMimeIcon(context, mimeType, authority, id, mMode);
         }
     }

     /**
      * Returns a mime icon or package icon for a {@link DocumentInfo}.
      */
     public Drawable getDocumentIcon(Context context, DocumentInfo doc) {
         return getDocumentIcon(
                 context, doc.authority, doc.documentId, doc.mimeType, doc.icon);
     }
 }
	/*
	* Copyright (C) 2015 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.documentsui.dirlist;

	import static com.android.documentsui.base.Shared.VERBOSE;
	import static com.android.documentsui.base.State.MODE_GRID;
	import static com.android.documentsui.base.State.MODE_LIST;

	import android.content.ContentProviderClient;
	import android.content.ContentResolver;
	import android.content.Context;
	import android.graphics.Bitmap;
	import android.graphics.Point;
	import android.graphics.drawable.Drawable;
	import android.net.Uri;
	import android.os.AsyncTask;
	import android.os.CancellationSignal;
	import android.os.OperationCanceledException;
	import android.provider.DocumentsContract;
	import android.provider.DocumentsContract.Document;
	import android.support.annotation.Nullable;
	import android.util.Log;
	import android.view.View;
	import android.widget.ImageView;

	import com.android.documentsui.DocumentsApplication;
	import com.android.documentsui.IconUtils;
	import com.android.documentsui.ProviderExecutor;
	import com.android.documentsui.ProviderExecutor.Preemptable;
	import com.android.documentsui.R;
	import com.android.documentsui.ThumbnailCache;
	import com.android.documentsui.ThumbnailCache.Result;
	import com.android.documentsui.base.DocumentInfo;
	import com.android.documentsui.base.MimeTypes;
	import com.android.documentsui.base.State;
	import com.android.documentsui.base.State.ViewMode;

	import java.util.function.BiConsumer;

	/**
	* A class to assist with loading and managing the Images (i.e. thumbnails and icons) associated
	* with items in the directory listing.
	*/
	public class IconHelper {
	private static final String TAG = "IconHelper";

	// Two animations applied to image views. The first is used to switch mime icon and thumbnail.
	// The second is used when we need to update thumbnail.
	private static final BiConsumer<View, View> ANIM_FADE_IN = (mime, thumb) -> {
	float alpha = mime.getAlpha();
	mime.animate().alpha(0f).start();
	thumb.setAlpha(0f);
	thumb.animate().alpha(alpha).start();
	};
	private static final BiConsumer<View, View> ANIM_NO_OP = (mime, thumb) -> {};

	private final Context mContext;
	private final ThumbnailCache mThumbnailCache;

	// The display mode (MODE_GRID, MODE_LIST, etc).
	private int mMode;
	private Point mCurrentSize;
	private boolean mThumbnailsEnabled = true;

	/**
	* @param context
	* @param mode MODE_GRID or MODE_LIST
	*/
	public IconHelper(Context context, int mode) {
	mContext = context;
	setViewMode(mode);
	mThumbnailCache = DocumentsApplication.getThumbnailCache(context);
	}

	/**
	* Enables or disables thumbnails. When thumbnails are disabled, mime icons (or custom icons, if
	* specified by the document) are used instead.
	*
	* @param enabled
	*/
	public void setThumbnailsEnabled(boolean enabled) {
	mThumbnailsEnabled = enabled;
	}

	/**
	* Sets the current display mode. This affects the thumbnail sizes that are loaded.
	*
	* @param mode See {@link State.MODE_LIST} and {@link State.MODE_GRID}.
	*/
	public void setViewMode(@ViewMode int mode) {
	mMode = mode;
	int thumbSize = getThumbSize(mode);
	mCurrentSize = new Point(thumbSize, thumbSize);
	}

	private int getThumbSize(int mode) {
	int thumbSize;
	switch (mode) {
	case MODE_GRID:
	thumbSize = mContext.getResources().getDimensionPixelSize(R.dimen.grid_width);
	break;
	case MODE_LIST:
	thumbSize = mContext.getResources().getDimensionPixelSize(
	R.dimen.list_item_thumbnail_size);
	break;
	default:
	throw new IllegalArgumentException("Unsupported layout mode: " + mode);
	}
	return thumbSize;
	}

	/**
	* Cancels any ongoing load operations associated with the given ImageView.
	*
	* @param icon
	*/
	public void stopLoading(ImageView icon) {
	final LoaderTask oldTask = (LoaderTask) icon.getTag();
	if (oldTask != null) {
	oldTask.preempt();
	icon.setTag(null);
	}
	}

	/** Internal task for loading thumbnails asynchronously. */
	private static class LoaderTask
	extends AsyncTask<Uri, Void, Bitmap>
	implements Preemptable {
	private final Uri mUri;
	private final ImageView mIconMime;
	private final ImageView mIconThumb;
	private final Point mThumbSize;
	private final long mLastModified;

	// A callback to apply animation to image views after the thumbnail is loaded.
	private final BiConsumer<View, View> mImageAnimator;

	private final CancellationSignal mSignal;

	public LoaderTask(Uri uri, ImageView iconMime, ImageView iconThumb,
	Point thumbSize, long lastModified, BiConsumer<View, View> animator) {
	mUri = uri;
	mIconMime = iconMime;
	mIconThumb = iconThumb;
	mThumbSize = thumbSize;
	mImageAnimator = animator;
	mLastModified = lastModified;
	mSignal = new CancellationSignal();
	if (VERBOSE) Log.v(TAG, "Starting icon loader task for " + mUri);
	}

	@Override
	public void preempt() {
	if (VERBOSE) Log.v(TAG, "Icon loader task for " + mUri + " was cancelled.");
	cancel(false);
	mSignal.cancel();
	}

	@Override
	protected Bitmap doInBackground(Uri... params) {
	if (isCancelled()) {
	return null;
	}

	final Context context = mIconThumb.getContext();
	final ContentResolver resolver = context.getContentResolver();

	ContentProviderClient client = null;
	Bitmap result = null;
	try {
	client = DocumentsApplication.acquireUnstableProviderOrThrow(
	resolver, mUri.getAuthority());
	result = DocumentsContract.getDocumentThumbnail(client, mUri, mThumbSize, mSignal);
	if (result != null) {
	final ThumbnailCache cache = DocumentsApplication.getThumbnailCache(context);
	cache.putThumbnail(mUri, mThumbSize, result, mLastModified);
	}
	} catch (Exception e) {
	if (!(e instanceof OperationCanceledException)) {
	Log.w(TAG, "Failed to load thumbnail for " + mUri + ": " + e);
	}
	} finally {
	ContentProviderClient.releaseQuietly(client);
	}
	return result;
	}

	@Override
	protected void onPostExecute(Bitmap result) {
	if (VERBOSE) Log.v(TAG, "Loader task for " + mUri + " completed");

	if (mIconThumb.getTag() == this && result != null) {
	mIconThumb.setTag(null);
	mIconThumb.setImageBitmap(result);

	mImageAnimator.accept(mIconMime, mIconThumb);
	}
	}
	}

	/**
	* Load thumbnails for a directory list item.
	*
	* @param doc The document
	* @param iconThumb The itemview's thumbnail icon.
	* @param iconMime The itemview's mime icon. Hidden when iconThumb is shown.
	* @param subIconMime The second itemview's mime icon. Always visible.
	* @return
	*/
	public void load(
	DocumentInfo doc,
	ImageView iconThumb,
	ImageView iconMime,
	@Nullable ImageView subIconMime) {
	load(doc.derivedUri, doc.mimeType, doc.flags, doc.icon, doc.lastModified,
	iconThumb, iconMime, subIconMime);
	}

	/**
	* Load thumbnails for a directory list item.
	*
	* @param uri The URI for the file being represented.
	* @param mimeType The mime type of the file being represented.
	* @param docFlags Flags for the file being represented.
	* @param docIcon Custom icon (if any) for the file being requested.
	* @param docLastModified the last modified value of the file being requested.
	* @param iconThumb The itemview's thumbnail icon.
	* @param iconMime The itemview's mime icon. Hidden when iconThumb is shown.
	* @param subIconMime The second itemview's mime icon. Always visible.
	* @return
	*/
	public void load(Uri uri, String mimeType, int docFlags, int docIcon, long docLastModified,
	ImageView iconThumb, ImageView iconMime, @Nullable ImageView subIconMime) {
	boolean loadedThumbnail = false;

	final String docAuthority = uri.getAuthority();

	final boolean supportsThumbnail = (docFlags & Document.FLAG_SUPPORTS_THUMBNAIL) != 0;
	final boolean allowThumbnail = (mMode == MODE_GRID)
	\|\| MimeTypes.mimeMatches(MimeTypes.VISUAL_MIMES, mimeType);
	final boolean showThumbnail = supportsThumbnail && allowThumbnail && mThumbnailsEnabled;
	if (showThumbnail) {
	loadedThumbnail =
	loadThumbnail(uri, docAuthority, docLastModified, iconThumb, iconMime);
	}

	final Drawable mimeIcon = getDocumentIcon(mContext, docAuthority,
	DocumentsContract.getDocumentId(uri), mimeType, docIcon);
	if (subIconMime != null) {
	setMimeIcon(subIconMime, mimeIcon);
	}

	if (loadedThumbnail) {
	hideImageView(iconMime);
	} else {
	// Add a mime icon if the thumbnail is not shown.
	setMimeIcon(iconMime, mimeIcon);
	hideImageView(iconThumb);
	}
	}

	private boolean loadThumbnail(Uri uri, String docAuthority, long docLastModified,
	ImageView iconThumb, ImageView iconMime) {
	final Result result = mThumbnailCache.getThumbnail(uri, mCurrentSize);

	try {
	final Bitmap cachedThumbnail = result.getThumbnail();
	iconThumb.setImageBitmap(cachedThumbnail);

	boolean stale = (docLastModified > result.getLastModified());
	if (VERBOSE) Log.v(TAG,
	String.format("Load thumbnail for %s, got result %d and stale %b.",
	uri.toString(), result.getStatus(), stale));
	if (!result.isExactHit() \|\| stale) {
	final BiConsumer<View, View> animator =
	(cachedThumbnail == null ? ANIM_FADE_IN : ANIM_NO_OP);
	final LoaderTask task = new LoaderTask(uri, iconMime, iconThumb, mCurrentSize,
	docLastModified, animator);

	iconThumb.setTag(task);

	ProviderExecutor.forAuthority(docAuthority).execute(task);
	}

	return result.isHit();
	} finally {
	result.recycle();
	}
	}

	private void setMimeIcon(ImageView view, Drawable icon) {
	view.setImageDrawable(icon);
	view.setAlpha(1f);
	}

	private void hideImageView(ImageView view) {
	view.setImageDrawable(null);
	view.setAlpha(0f);
	}

	private Drawable getDocumentIcon(
	Context context, String authority, String id, String mimeType, int icon) {
	if (icon != 0) {
	return IconUtils.loadPackageIcon(context, authority, icon);
	} else {
	return IconUtils.loadMimeIcon(context, mimeType, authority, id, mMode);
	}
	}

	/**
	* Returns a mime icon or package icon for a {@link DocumentInfo}.
	*/
	public Drawable getDocumentIcon(Context context, DocumentInfo doc) {
	return getDocumentIcon(
	context, doc.authority, doc.documentId, doc.mimeType, doc.icon);
	}
	}