fullscreen: work with uri/path & flutter image widget

android/app/src/main/java/deckers/thibault/aves/MainActivity.java

@@ -93,7 +93,8 @@ public class MainActivity extends FlutterActivity {
                         case "cancelGetImageBytes": {
                             String uri = call.argument("uri");
                             thumbnailFetcher.cancel(uri);
-                            result.success(null);
+                            // do not send `null`, as it closes the channel
+                            result.success("");
                             break;
                         }
                         default:
@@ -214,12 +215,14 @@ class BitmapWorkerTask extends AsyncTask<BitmapWorkerTask.MyTaskParams, Void, Bi
                     bmp.compress(Bitmap.CompressFormat.JPEG, 90, stream);
                     data = stream.toByteArray();
                 }
+            } catch (InterruptedException e) {
+                Log.d(LOG_TAG, "getImageBytes with uri=" + entry.getUri() + " interrupted");
             } catch (Exception e) {
                 e.printStackTrace();
             }
             Glide.with(activity).clear(target);
         } else {
-            Log.d(LOG_TAG, "getImageBytes with uri=" + entry.getUri() + " (cancelled)");
+            Log.d(LOG_TAG, "getImageBytes with uri=" + entry.getUri() + " cancelled");
         }
         return new MyTaskResult(p, data);
     }

android/app/src/main/java/deckers/thibault/aves/model/ImageEntry.java

@@ -1,24 +1,16 @@
 package deckers.thibault.aves.model;
 
-import android.content.ContentUris;
-import android.content.Context;
 import android.net.Uri;
-import android.provider.MediaStore;
 import android.support.annotation.Nullable;
 import android.text.format.DateUtils;
 
 import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
-import java.io.InputStream;
 import java.util.HashMap;
 import java.util.Map;
 
 import deckers.thibault.aves.utils.Constants;
 
 public class ImageEntry {
-    private static final Uri mediaStoreContentUri = MediaStore.Files.getContentUri("external");
-
     // from source
     private String path; // best effort to get local path from content providers
     private long contentId; // should be defined for mediastore, use full URI otherwise
@@ -39,11 +31,13 @@ public class ImageEntry {
         init();
     }
 
-    public ImageEntry(String path, long id, String mimeType, int width, int height, int orientationDegrees, long sizeBytes,
+    // uri: content provider uri
+    // path: FileUtils.getPathFromUri(activity, itemUri) is useful (for Download, File, etc.) but is slower than directly using `MediaStore.MediaColumns.DATA` from the MediaStore query
+    public ImageEntry(Uri uri, String path, long id, String mimeType, int width, int height, int orientationDegrees, long sizeBytes,
                       String title, long dateModifiedSecs, long dateTakenMillis, String bucketDisplayName, long durationMillis) {
+        this.uri = uri;
         this.path = path;
         this.contentId = id;
-        this.uri = null;
         this.mimeType = mimeType;
         this.width = width;
         this.height = height;
@@ -59,6 +53,7 @@ public class ImageEntry {
 
     public ImageEntry(Map map) {
         this(
+                Uri.parse((String) map.get("uri")),
                 (String) map.get("path"),
                 toLong(map.get("contentId")),
                 (String) map.get("mimeType"),
@@ -76,6 +71,7 @@ public class ImageEntry {
 
     public static Map toMap(ImageEntry entry) {
         return new HashMap<String, Object>() {{
+            put("uri", entry.uri.toString());
             put("path", entry.path);
             put("contentId", entry.contentId);
             put("mimeType", entry.mimeType);
@@ -88,8 +84,6 @@ public class ImageEntry {
             put("sourceDateTakenMillis", entry.sourceDateTakenMillis);
             put("bucketDisplayName", entry.bucketDisplayName);
             put("durationMillis", entry.durationMillis);
-            //
-            put("uri", entry.getUri().toString());
         }};
     }
 
@@ -97,6 +91,10 @@ public class ImageEntry {
         isVideo = mimeType.startsWith(Constants.MIME_VIDEO);
     }
 
+    public Uri getUri() {
+        return uri;
+    }
+
     @Nullable
     public String getPath() {
         return path;
@@ -106,18 +104,6 @@ public class ImageEntry {
         return path == null ? null : new File(path).getName();
     }
 
-    public InputStream getInputStream(Context context) throws FileNotFoundException {
-        // FileInputStream is faster than input stream from ContentResolver
-        return path != null ? new FileInputStream(path) : context.getContentResolver().openInputStream(getUri());
-    }
-
-    public Uri getUri() {
-        if (uri != null) {
-            return uri;
-        }
-        return ContentUris.withAppendedId(mediaStoreContentUri, contentId);
-    }
-
     public boolean isVideo() {
         return isVideo;
     }

android/app/src/main/java/deckers/thibault/aves/model/provider/MediaStoreImageProvider.java

@@ -1,6 +1,7 @@
 package deckers.thibault.aves.model.provider;
 
 import android.app.Activity;
+import android.content.ContentUris;
 import android.database.Cursor;
 import android.net.Uri;
 import android.provider.MediaStore;
@@ -39,22 +40,24 @@ public class MediaStoreImageProvider {
 
 
     public List<ImageEntry> fetchAll(Activity activity) {
-        return fetch(activity, FILES_URI, null);
+        return fetch(activity, FILES_URI);
     }
 
-    public List<ImageEntry> fetch(final Activity activity, final Uri uri, String mimeType) {
+    private List<ImageEntry> fetch(final Activity activity, final Uri queryUri) {
         ArrayList<ImageEntry> entries = new ArrayList<>();
 
         // URI should refer to the "files" table, not to the "images" or "videos" one,
         // as our projection includes a mix of columns from both
-        Uri filesUri = uri;
+        Uri filesUri = queryUri;
-        if (!FILES_URI.equals(uri)) {
+        if (!FILES_URI.equals(queryUri)) {
-            String id = uri.getLastPathSegment();
+            String id = queryUri.getLastPathSegment();
             filesUri = Uri.withAppendedPath(FILES_URI, id);
         }
 
+        String orderBy = MediaStore.Images.ImageColumns.DATE_TAKEN + " DESC";
+
         try {
-            Cursor cursor = activity.getContentResolver().query(filesUri, PROJECTION, SELECTION, null, null);
+            Cursor cursor = activity.getContentResolver().query(filesUri, PROJECTION, SELECTION, null, orderBy);
             if (cursor != null) {
                 Log.d(LOG_TAG, "fetch query returned " + cursor.getCount() + " entries");
 
@@ -72,9 +75,12 @@ public class MediaStoreImageProvider {
                 int durationColumn = cursor.getColumnIndexOrThrow(MediaStore.Video.Media.DURATION);
 
                 while (cursor.moveToNext()) {
+                    long contentId = cursor.getLong(idColumn);
+                    Uri itemUri = ContentUris.withAppendedId(FILES_URI, contentId);
                     ImageEntry imageEntry = new ImageEntry(
+                            itemUri,
                             cursor.getString(pathColumn),
-                            cursor.getLong(idColumn),
+                            contentId,
                             cursor.getString(mimeTypeColumn),
                             cursor.getInt(widthColumn),
                             cursor.getInt(heightColumn),

android/app/src/main/java/deckers/thibault/aves/utils/FileUtils.java

@@ -0,0 +1,211 @@
+/*
+ * Copyright (C) 2007-2008 OpenIntents.org
+ *
+ * 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.
+ *
+ * This file was modified by the Flutter authors from the following original file:
+ * https://raw.githubusercontent.com/iPaulPro/aFileChooser/master/aFileChooser/src/com/ipaulpro/afilechooser/utils/FileUtils.java
+ */
+
+// TLAD: copied from https://raw.githubusercontent.com/flutter/plugins/master/packages/image_picker/android/src/main/java/io/flutter/plugins/imagepicker/FileUtils.java
+
+package deckers.thibault.aves.utils;
+
+import android.annotation.SuppressLint;
+import android.content.ContentUris;
+import android.content.Context;
+import android.database.Cursor;
+import android.net.Uri;
+import android.os.Build;
+import android.os.Environment;
+import android.provider.DocumentsContract;
+import android.provider.MediaStore;
+import android.text.TextUtils;
+import android.webkit.MimeTypeMap;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+public class FileUtils {
+
+  public String getPathFromUri(final Context context, final Uri uri) {
+    String path = getPathFromLocalUri(context, uri);
+    if (path == null) {
+      path = getPathFromRemoteUri(context, uri);
+    }
+    return path;
+  }
+
+  @SuppressLint("NewApi")
+  private String getPathFromLocalUri(final Context context, final Uri uri) {
+    final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
+
+    if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
+      if (isExternalStorageDocument(uri)) {
+        final String docId = DocumentsContract.getDocumentId(uri);
+        final String[] split = docId.split(":");
+        final String type = split[0];
+
+        if ("primary".equalsIgnoreCase(type)) {
+          return Environment.getExternalStorageDirectory() + "/" + split[1];
+        }
+      } else if (isDownloadsDocument(uri)) {
+        final String id = DocumentsContract.getDocumentId(uri);
+
+        if (!TextUtils.isEmpty(id)) {
+          try {
+            final Uri contentUri =
+                ContentUris.withAppendedId(
+                    Uri.parse(Environment.DIRECTORY_DOWNLOADS), Long.valueOf(id));
+            return getDataColumn(context, contentUri, null, null);
+          } catch (NumberFormatException e) {
+            return null;
+          }
+        }
+
+      } else if (isMediaDocument(uri)) {
+        final String docId = DocumentsContract.getDocumentId(uri);
+        final String[] split = docId.split(":");
+        final String type = split[0];
+
+        Uri contentUri = null;
+        if ("image".equals(type)) {
+          contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
+        } else if ("video".equals(type)) {
+          contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
+        } else if ("audio".equals(type)) {
+          contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
+        }
+
+        final String selection = "_id=?";
+        final String[] selectionArgs = new String[] {split[1]};
+
+        return getDataColumn(context, contentUri, selection, selectionArgs);
+      }
+    } else if ("content".equalsIgnoreCase(uri.getScheme())) {
+
+      // Return the remote address
+      if (isGooglePhotosUri(uri)) {
+        return null;
+      }
+
+      return getDataColumn(context, uri, null, null);
+    } else if ("file".equalsIgnoreCase(uri.getScheme())) {
+      return uri.getPath();
+    }
+
+    return null;
+  }
+
+  private static String getDataColumn(
+      Context context, Uri uri, String selection, String[] selectionArgs) {
+
+    final String column = "_data";
+    final String[] projection = {column};
+    try (Cursor cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null)) {
+      if (cursor != null && cursor.moveToFirst()) {
+        final int column_index = cursor.getColumnIndex(column);
+
+        //yandex.disk and dropbox do not have _data column
+        if (column_index == -1) {
+          return null;
+        }
+
+        return cursor.getString(column_index);
+      }
+    }
+    return null;
+  }
+
+  private static String getPathFromRemoteUri(final Context context, final Uri uri) {
+    // The code below is why Java now has try-with-resources and the Files utility.
+    File file = null;
+    InputStream inputStream = null;
+    OutputStream outputStream = null;
+    boolean success = false;
+    try {
+      String extension = getImageExtension(context, uri);
+      inputStream = context.getContentResolver().openInputStream(uri);
+      file = File.createTempFile("image_picker", extension, context.getCacheDir());
+      outputStream = new FileOutputStream(file);
+      if (inputStream != null) {
+        copy(inputStream, outputStream);
+        success = true;
+      }
+    } catch (IOException ignored) {
+    } finally {
+      try {
+        if (inputStream != null) inputStream.close();
+      } catch (IOException ignored) {
+      }
+      try {
+        if (outputStream != null) outputStream.close();
+      } catch (IOException ignored) {
+        // If closing the output stream fails, we cannot be sure that the
+        // target file was written in full. Flushing the stream merely moves
+        // the bytes into the OS, not necessarily to the file.
+        success = false;
+      }
+    }
+    return success ? file.getPath() : null;
+  }
+
+  /** @return extension of image with dot, or default .jpg if it none. */
+  private static String getImageExtension(Context context, Uri uriImage) {
+    String extension = null;
+
+    try (Cursor cursor = context
+            .getContentResolver()
+            .query(uriImage, new String[]{MediaStore.MediaColumns.MIME_TYPE}, null, null, null)) {
+
+      if (cursor != null && cursor.moveToNext()) {
+        String mimeType = cursor.getString(0);
+
+        extension = MimeTypeMap.getSingleton().getExtensionFromMimeType(mimeType);
+      }
+    }
+
+    if (extension == null) {
+      //default extension for matches the previous behavior of the plugin
+      extension = "jpg";
+    }
+    return "." + extension;
+  }
+
+  private static void copy(InputStream in, OutputStream out) throws IOException {
+    final byte[] buffer = new byte[4 * 1024];
+    int bytesRead;
+    while ((bytesRead = in.read(buffer)) != -1) {
+      out.write(buffer, 0, bytesRead);
+    }
+    out.flush();
+  }
+
+  private static boolean isExternalStorageDocument(Uri uri) {
+    return "com.android.externalstorage.documents".equals(uri.getAuthority());
+  }
+
+  private static boolean isDownloadsDocument(Uri uri) {
+    return "com.android.providers.downloads.documents".equals(uri.getAuthority());
+  }
+
+  private static boolean isMediaDocument(Uri uri) {
+    return "com.android.providers.media.documents".equals(uri.getAuthority());
+  }
+
+  private static boolean isGooglePhotosUri(Uri uri) {
+    return "com.google.android.apps.photos.contentprovider".equals(uri.getAuthority());
+  }
+}

lib/image_fullscreen_page.dart

@@ -1,8 +1,9 @@
+import 'dart:io';
 import 'dart:math';
 import 'dart:typed_data';
 
-import 'package:aves/model/image_fetcher.dart';
 import 'package:flutter/material.dart';
+import 'package:transparent_image/transparent_image.dart';
 
 class ImageFullscreenPage extends StatefulWidget {
   final Map entry;
@@ -15,14 +16,16 @@ class ImageFullscreenPage extends StatefulWidget {
 }
 
 class ImageFullscreenPageState extends State<ImageFullscreenPage> {
-  Future<Uint8List> loader;
-
   int get imageWidth => widget.entry['width'];
 
   int get imageHeight => widget.entry['height'];
 
   String get uri => widget.entry['uri'];
 
+  String get path => widget.entry['path'];
+
+  double requestWidth, requestHeight;
+
   @override
   void initState() {
     super.initState();
@@ -30,30 +33,29 @@ class ImageFullscreenPageState extends State<ImageFullscreenPage> {
 
   @override
   void dispose() {
-    ImageFetcher.cancelGetImageBytes(uri);
     super.dispose();
   }
 
   @override
   Widget build(BuildContext context) {
-    if (loader == null) {
+    if (requestWidth == null || requestHeight == null) {
       var mediaQuery = MediaQuery.of(context);
       var screenSize = mediaQuery.size;
       var dpr = mediaQuery.devicePixelRatio;
-      var requestWidth = imageWidth * dpr;
+      requestWidth = imageWidth * dpr;
-      var requestHeight = imageHeight * dpr;
+      requestHeight = imageHeight * dpr;
       if (imageWidth > screenSize.width || imageHeight > screenSize.height) {
         var ratio = max(imageWidth / screenSize.width, imageHeight / screenSize.height);
         requestWidth /= ratio;
         requestHeight /= ratio;
       }
-      loader = ImageFetcher.getImageBytes(widget.entry, requestWidth.round(), requestHeight.round());
     }
-    return FutureBuilder(
+    return MediaQuery.removeViewInsets(
-        future: loader,
+      context: context,
-        builder: (futureContext, AsyncSnapshot<Uint8List> snapshot) {
+      // remove bottom view insets to paint underneath the translucent navigation bar
-          var ready = snapshot.connectionState == ConnectionState.done && !snapshot.hasError;
+      removeBottom: true,
-          return Hero(
+      child: Scaffold(
+        body: Hero(
           tag: uri,
           child: Stack(
             children: [
@@ -62,21 +64,26 @@ class ImageFullscreenPageState extends State<ImageFullscreenPage> {
                     ? CircularProgressIndicator()
                     : Image.memory(
                         widget.thumbnail,
-                          width: imageWidth.toDouble(),
+                        width: requestWidth,
-                          height: imageHeight.toDouble(),
+                        height: requestHeight,
                         fit: BoxFit.contain,
                       ),
               ),
-                if (ready)
+              Center(
-                  Image.memory(
+                child: FadeInImage(
-                    snapshot.data,
+                  placeholder: MemoryImage(kTransparentImage),
-                    width: imageWidth.toDouble(),
+                  image: FileImage(File(path)),
-                    height: imageHeight.toDouble(),
+                  fadeOutDuration: Duration(milliseconds: 1),
+                  fadeInDuration: Duration(milliseconds: 200),
+                  width: requestWidth,
+                  height: requestHeight,
                   fit: BoxFit.contain,
                 ),
+              ),
             ],
           ),
+        ),
+      ),
     );
-        });
   }
 }