Add image loading plugin based on picasso library

build.gradle

@@ -71,7 +71,8 @@ ext {
             'prism4j'                 : 'ru.noties:prism4j:1.1.0',
             'debug'                   : 'ru.noties:debug:3.0.0@jar',
             'adapt'                   : 'ru.noties:adapt:1.1.0',
-            'dagger'                  : "com.google.dagger:dagger:$daggerVersion"
+            'dagger'                  : "com.google.dagger:dagger:$daggerVersion",
+            'picasso'                 : "com.squareup.picasso:picasso:2.71828"
     ]
 
     deps['annotationProcessor'] = [

markwon-core/src/main/java/ru/noties/markwon/core/CorePlugin.java

@@ -14,6 +14,7 @@ import org.commonmark.node.Emphasis;
 import org.commonmark.node.FencedCodeBlock;
 import org.commonmark.node.HardLineBreak;
 import org.commonmark.node.Heading;
+import org.commonmark.node.Image;
 import org.commonmark.node.IndentedCodeBlock;
 import org.commonmark.node.Link;
 import org.commonmark.node.ListBlock;
@@ -30,6 +31,8 @@ import ru.noties.markwon.AbstractMarkwonPlugin;
 import ru.noties.markwon.MarkwonConfiguration;
 import ru.noties.markwon.MarkwonSpansFactory;
 import ru.noties.markwon.MarkwonVisitor;
+import ru.noties.markwon.RenderProps;
+import ru.noties.markwon.SpanFactory;
 import ru.noties.markwon.core.factory.BlockQuoteSpanFactory;
 import ru.noties.markwon.core.factory.CodeBlockSpanFactory;
 import ru.noties.markwon.core.factory.CodeSpanFactory;
@@ -40,6 +43,7 @@ import ru.noties.markwon.core.factory.ListItemSpanFactory;
 import ru.noties.markwon.core.factory.StrongEmphasisSpanFactory;
 import ru.noties.markwon.core.factory.ThematicBreakSpanFactory;
 import ru.noties.markwon.core.spans.OrderedListItemSpan;
+import ru.noties.markwon.image.ImageProps;
 
 /**
  * @see CoreProps
@@ -64,6 +68,7 @@ public class CorePlugin extends AbstractMarkwonPlugin {
         code(builder);
         fencedCodeBlock(builder);
         indentedCodeBlock(builder);
+        image(builder);
         bulletList(builder);
         orderedList(builder);
         listItem(builder);
@@ -197,6 +202,53 @@ public class CorePlugin extends AbstractMarkwonPlugin {
         });
     }
 
+    // @since 4.0.0-SNAPSHOT
+    // his method is moved from ImagesPlugin. Alternative implementations must set SpanFactory
+    // for Image node in order for this visitor to function
+    private static void image(MarkwonVisitor.Builder builder) {
+        builder.on(Image.class, new MarkwonVisitor.NodeVisitor<Image>() {
+            @Override
+            public void visit(@NonNull MarkwonVisitor visitor, @NonNull Image image) {
+
+                // if there is no image spanFactory, ignore
+                final SpanFactory spanFactory = visitor.configuration().spansFactory().get(Image.class);
+                if (spanFactory == null) {
+                    visitor.visitChildren(image);
+                    return;
+                }
+
+                final int length = visitor.length();
+
+                visitor.visitChildren(image);
+
+                // we must check if anything _was_ added, as we need at least one char to render
+                if (length == visitor.length()) {
+                    visitor.builder().append('\uFFFC');
+                }
+
+                final MarkwonConfiguration configuration = visitor.configuration();
+
+                final Node parent = image.getParent();
+                final boolean link = parent instanceof Link;
+
+                final String destination = configuration
+                        .urlProcessor()
+                        .process(image.getDestination());
+
+                final RenderProps props = visitor.renderProps();
+
+                // apply image properties
+                // Please note that we explicitly set IMAGE_SIZE to null as we do not clear
+                // properties after we applied span (we could though)
+                ImageProps.DESTINATION.set(props, destination);
+                ImageProps.REPLACEMENT_TEXT_IS_LINK.set(props, link);
+                ImageProps.IMAGE_SIZE.set(props, null);
+
+                visitor.setSpans(length, spanFactory.getSpans(configuration, props));
+            }
+        });
+    }
+
     @VisibleForTesting
     static void visitCodeBlock(
             @NonNull MarkwonVisitor visitor,

markwon-core/src/main/java/ru/noties/markwon/image/AsyncDrawable.java

@@ -261,7 +261,8 @@ public class AsyncDrawable extends Drawable {
         if (hasResult()) {
             out = result.getIntrinsicWidth();
         } else {
-            out = 0;
+            // @since 4.0.0-SNAPSHOT, must not be zero in order to receive canvas dimensions
+            out = 1;
         }
         return out;
     }
@@ -272,7 +273,8 @@ public class AsyncDrawable extends Drawable {
         if (hasResult()) {
             out = result.getIntrinsicHeight();
         } else {
-            out = 0;
+            // @since 4.0.0-SNAPSHOT, must not be zero in order to receive canvas dimensions
+            out = 1;
         }
         return out;
     }
@@ -290,4 +292,16 @@ public class AsyncDrawable extends Drawable {
                 ? imageSizeResolver.resolveImageSize(imageSize, result.getBounds(), canvasWidth, textSize)
                 : result.getBounds();
     }
+
+    @Override
+    public String toString() {
+        return "AsyncDrawable{" +
+                "destination='" + destination + '\'' +
+                ", imageSize=" + imageSize +
+                ", result=" + result +
+                ", canvasWidth=" + canvasWidth +
+                ", textSize=" + textSize +
+                ", waitingForDimensions=" + waitingForDimensions +
+                '}';
+    }
 }

markwon-core/src/main/java/ru/noties/markwon/image/AsyncDrawableScheduler.java

@@ -23,6 +23,7 @@ public abstract class AsyncDrawableScheduler {
         // hm... we need the same thing for unschedule then... we can check if last hash is !null,
         // if it's not -> unschedule, else ignore
 
+        // @since 4.0.0-SNAPSHOT
         final Integer lastTextHashCode =
                 (Integer) textView.getTag(R.id.markwon_drawables_scheduler_last_text_hashcode);
         final int textHashCode = textView.getText().hashCode();
@@ -67,6 +68,7 @@ public abstract class AsyncDrawableScheduler {
     // must be called when text manually changed in TextView
     public static void unschedule(@NonNull TextView view) {
 
+        // @since 4.0.0-SNAPSHOT
         if (view.getTag(R.id.markwon_drawables_scheduler_last_text_hashcode) == null) {
             return;
         }

markwon-image-picasso/build.gradle

@@ -0,0 +1,21 @@
+apply plugin: 'com.android.library'
+
+android {
+
+    compileSdkVersion config['compile-sdk']
+    buildToolsVersion config['build-tools']
+
+    defaultConfig {
+        minSdkVersion config['min-sdk']
+        targetSdkVersion config['target-sdk']
+        versionCode 1
+        versionName version
+    }
+}
+
+dependencies {
+    api project(':markwon-core')
+    api deps['picasso']
+}
+
+registerArtifact(this)

markwon-image-picasso/gradle.properties

@@ -0,0 +1,4 @@
+POM_NAME=Image
+POM_ARTIFACT_ID=image-picasso
+POM_DESCRIPTION=Markwon image loading module (based on Picasso library)
+POM_PACKAGING=aar

markwon-image-picasso/src/main/AndroidManifest.xml

@@ -0,0 +1 @@
+<manifest package="ru.noties.markwon.image.picasso" />

markwon-image-picasso/src/main/java/ru/noties/markwon/image/picasso/PicassoImagesPlugin.java

@@ -0,0 +1,177 @@
+package ru.noties.markwon.image.picasso;
+
+import android.content.Context;
+import android.content.res.Resources;
+import android.graphics.Bitmap;
+import android.graphics.drawable.BitmapDrawable;
+import android.graphics.drawable.Drawable;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.text.Spanned;
+import android.widget.TextView;
+
+import com.squareup.picasso.Picasso;
+import com.squareup.picasso.RequestCreator;
+import com.squareup.picasso.Target;
+
+import org.commonmark.node.Image;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import ru.noties.markwon.AbstractMarkwonPlugin;
+import ru.noties.markwon.MarkwonConfiguration;
+import ru.noties.markwon.MarkwonSpansFactory;
+import ru.noties.markwon.image.AsyncDrawable;
+import ru.noties.markwon.image.AsyncDrawableLoader;
+import ru.noties.markwon.image.AsyncDrawableScheduler;
+import ru.noties.markwon.image.DrawableUtils;
+import ru.noties.markwon.image.ImageSpanFactory;
+
+/**
+ * @since 4.0.0-SNAPSHOT
+ */
+public class PicassoImagesPlugin extends AbstractMarkwonPlugin {
+
+    public interface PicassoStore {
+
+        @NonNull
+        RequestCreator load(@NonNull AsyncDrawable drawable);
+
+        void cancel(@NonNull AsyncDrawable drawable);
+    }
+
+    @NonNull
+    public static PicassoImagesPlugin create(@NonNull Context context) {
+        return create(new Picasso.Builder(context).build());
+    }
+
+    @NonNull
+    public static PicassoImagesPlugin create(@NonNull final Picasso picasso) {
+        return create(new PicassoStore() {
+            @NonNull
+            @Override
+            public RequestCreator load(@NonNull AsyncDrawable drawable) {
+                return picasso.load(drawable.getDestination())
+                        .tag(drawable);
+            }
+
+            @Override
+            public void cancel(@NonNull AsyncDrawable drawable) {
+                picasso.cancelTag(drawable);
+            }
+        });
+    }
+
+    @NonNull
+    public static PicassoImagesPlugin create(@NonNull PicassoStore picassoStore) {
+        return new PicassoImagesPlugin(picassoStore);
+    }
+
+    private final PicassoAsyncDrawableLoader picassoAsyncDrawableLoader;
+
+    PicassoImagesPlugin(@NonNull PicassoStore picassoStore) {
+        this.picassoAsyncDrawableLoader = new PicassoAsyncDrawableLoader(picassoStore);
+    }
+
+    @Override
+    public void configureConfiguration(@NonNull MarkwonConfiguration.Builder builder) {
+        builder.asyncDrawableLoader(picassoAsyncDrawableLoader);
+    }
+
+    @Override
+    public void configureSpansFactory(@NonNull MarkwonSpansFactory.Builder builder) {
+        builder.setFactory(Image.class, new ImageSpanFactory());
+    }
+
+    @Override
+    public void beforeSetText(@NonNull TextView textView, @NonNull Spanned markdown) {
+        AsyncDrawableScheduler.unschedule(textView);
+    }
+
+    @Override
+    public void afterSetText(@NonNull TextView textView) {
+        AsyncDrawableScheduler.schedule(textView);
+    }
+
+    private static class PicassoAsyncDrawableLoader extends AsyncDrawableLoader {
+
+        private final PicassoStore picassoStore;
+        private final Map<AsyncDrawable, AsyncDrawableTarget> cache = new HashMap<>(2);
+
+        PicassoAsyncDrawableLoader(@NonNull PicassoStore picassoStore) {
+            this.picassoStore = picassoStore;
+        }
+
+        @Override
+        public void load(@NonNull AsyncDrawable drawable) {
+
+            // we must store hard-reference to target (otherwise it will be garbage-collected
+            // ad picasso internally stores a target in a weak-reference)
+            final AsyncDrawableTarget target = new AsyncDrawableTarget(drawable);
+            cache.put(drawable, target);
+
+            picassoStore.load(drawable)
+                    .into(target);
+        }
+
+        @Override
+        public void cancel(@NonNull AsyncDrawable drawable) {
+
+            cache.remove(drawable);
+
+            picassoStore.cancel(drawable);
+        }
+
+        @Nullable
+        @Override
+        public Drawable placeholder(@NonNull AsyncDrawable drawable) {
+            return null;
+        }
+
+        private class AsyncDrawableTarget implements Target {
+
+            private final AsyncDrawable drawable;
+
+            AsyncDrawableTarget(@NonNull AsyncDrawable drawable) {
+                this.drawable = drawable;
+            }
+
+            @Override
+            public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
+                if (cache.remove(drawable) != null) {
+                    if (drawable.isAttached() && bitmap != null) {
+                        final BitmapDrawable bitmapDrawable = new BitmapDrawable(Resources.getSystem(), bitmap);
+                        DrawableUtils.applyIntrinsicBounds(bitmapDrawable);
+                        drawable.setResult(bitmapDrawable);
+                    }
+                }
+            }
+
+            @Override
+            public void onBitmapFailed(Exception e, Drawable errorDrawable) {
+                if (cache.remove(drawable) != null) {
+                    if (errorDrawable != null
+                            && drawable.isAttached()) {
+                        DrawableUtils.applyIntrinsicBoundsIfEmpty(errorDrawable);
+                        drawable.setResult(errorDrawable);
+                    }
+                }
+                e.printStackTrace();
+            }
+
+            @Override
+            public void onPrepareLoad(Drawable placeHolderDrawable) {
+                if (placeHolderDrawable != null
+                        && canDeliver()) {
+                    DrawableUtils.applyIntrinsicBoundsIfEmpty(placeHolderDrawable);
+                    drawable.setResult(placeHolderDrawable);
+                }
+            }
+
+            private boolean canDeliver() {
+                return drawable.isAttached() && cache.containsKey(drawable);
+            }
+        }
+    }
+}

markwon-image/src/main/java/ru/noties/markwon/image/AsyncDrawableLoaderBuilder.java

@@ -73,13 +73,17 @@ class AsyncDrawableLoaderBuilder {
 
         isBuilt = true;
 
-        // if we have no schemeHandlers -> we cannot show anything
+        // we must have schemeHandlers registered (we will provide
-        // OR if we have no media decoders
+        // default media decoder if it's absent)
-        if (schemeHandlers.size() == 0
+        if (schemeHandlers.size() == 0) {
-                || (mediaDecoders.size() == 0 && defaultMediaDecoder == null)) {
             return new AsyncDrawableLoaderNoOp();
         }
 
+        // @since 4.0.0-SNAPSHOT
+        if (defaultMediaDecoder == null) {
+            defaultMediaDecoder = DefaultImageMediaDecoder.create();
+        }
+
         if (executorService == null) {
             executorService = Executors.newCachedThreadPool();
         }

markwon-image/src/main/java/ru/noties/markwon/image/ImagesPlugin.java

@@ -7,17 +7,12 @@ import android.text.Spanned;
 import android.widget.TextView;
 
 import org.commonmark.node.Image;
-import org.commonmark.node.Link;
-import org.commonmark.node.Node;
 
 import java.util.concurrent.ExecutorService;
 
 import ru.noties.markwon.AbstractMarkwonPlugin;
 import ru.noties.markwon.MarkwonConfiguration;
 import ru.noties.markwon.MarkwonSpansFactory;
-import ru.noties.markwon.MarkwonVisitor;
-import ru.noties.markwon.RenderProps;
-import ru.noties.markwon.SpanFactory;
 
 public class ImagesPlugin extends AbstractMarkwonPlugin {
 
@@ -147,51 +142,6 @@ public class ImagesPlugin extends AbstractMarkwonPlugin {
         builder.setFactory(Image.class, new ImageSpanFactory());
     }
 
-    @Override
-    public void configureVisitor(@NonNull MarkwonVisitor.Builder builder) {
-        builder.on(Image.class, new MarkwonVisitor.NodeVisitor<Image>() {
-            @Override
-            public void visit(@NonNull MarkwonVisitor visitor, @NonNull Image image) {
-
-                // if there is no image spanFactory, ignore
-                final SpanFactory spanFactory = visitor.configuration().spansFactory().get(Image.class);
-                if (spanFactory == null) {
-                    visitor.visitChildren(image);
-                    return;
-                }
-
-                final int length = visitor.length();
-
-                visitor.visitChildren(image);
-
-                // we must check if anything _was_ added, as we need at least one char to render
-                if (length == visitor.length()) {
-                    visitor.builder().append('\uFFFC');
-                }
-
-                final MarkwonConfiguration configuration = visitor.configuration();
-
-                final Node parent = image.getParent();
-                final boolean link = parent instanceof Link;
-
-                final String destination = configuration
-                        .urlProcessor()
-                        .process(image.getDestination());
-
-                final RenderProps props = visitor.renderProps();
-
-                // apply image properties
-                // Please note that we explicitly set IMAGE_SIZE to null as we do not clear
-                // properties after we applied span (we could though)
-                ImageProps.DESTINATION.set(props, destination);
-                ImageProps.REPLACEMENT_TEXT_IS_LINK.set(props, link);
-                ImageProps.IMAGE_SIZE.set(props, null);
-
-                visitor.setSpans(length, spanFactory.getSpans(configuration, props));
-            }
-        });
-    }
-
     @Override
     public void beforeSetText(@NonNull TextView textView, @NonNull Spanned markdown) {
         AsyncDrawableScheduler.unschedule(textView);

markwon-image/src/main/java/ru/noties/markwon/image/file/FileSchemeHandler.java

@@ -1,5 +1,6 @@
 package ru.noties.markwon.image.file;
 
+import android.content.Context;
 import android.content.res.AssetManager;
 import android.net.Uri;
 import android.support.annotation.NonNull;
@@ -35,6 +36,16 @@ public class FileSchemeHandler extends SchemeHandler {
         return new FileSchemeHandler(assetManager);
     }
 
+    /**
+     * @see #createWithAssets(AssetManager)
+     * @see ru.noties.markwon.urlprocessor.UrlProcessorAndroidAssets
+     * @since 4.0.0-SNAPSHOT
+     */
+    @NonNull
+    public static FileSchemeHandler createWithAssets(@NonNull Context context) {
+        return new FileSchemeHandler(context.getAssets());
+    }
+
     @NonNull
     public static FileSchemeHandler create() {
         return new FileSchemeHandler(null);

sample/build.gradle

@@ -44,6 +44,8 @@ dependencies {
     implementation project(':markwon-recycler')
     implementation project(':markwon-recycler-table')
 
+    implementation project(':markwon-image-picasso')
+
     deps.with {
         implementation it['support-recycler-view']
         implementation it['okhttp']

sample/src/main/java/ru/noties/markwon/sample/recycler/RecyclerActivity.java

@@ -2,6 +2,8 @@ package ru.noties.markwon.sample.recycler;
 
 import android.app.Activity;
 import android.content.Context;
+import android.graphics.Color;
+import android.graphics.drawable.ColorDrawable;
 import android.net.Uri;
 import android.os.Bundle;
 import android.support.annotation.NonNull;
@@ -10,6 +12,9 @@ import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
 import android.text.TextUtils;
 
+import com.squareup.picasso.Picasso;
+import com.squareup.picasso.RequestCreator;
+
 import org.commonmark.ext.gfm.tables.TableBlock;
 import org.commonmark.node.FencedCodeBlock;
 
@@ -26,11 +31,8 @@ import ru.noties.markwon.MarkwonConfiguration;
 import ru.noties.markwon.MarkwonVisitor;
 import ru.noties.markwon.core.CorePlugin;
 import ru.noties.markwon.html.HtmlPlugin;
-import ru.noties.markwon.image.DefaultImageMediaDecoder;
+import ru.noties.markwon.image.AsyncDrawable;
-import ru.noties.markwon.image.ImagesPlugin;
+import ru.noties.markwon.image.picasso.PicassoImagesPlugin;
-import ru.noties.markwon.image.file.FileSchemeHandler;
-import ru.noties.markwon.image.network.OkHttpNetworkSchemeHandler;
-import ru.noties.markwon.image.svg.SvgMediaDecoder;
 import ru.noties.markwon.recycler.MarkwonAdapter;
 import ru.noties.markwon.recycler.SimpleEntry;
 import ru.noties.markwon.recycler.table.TableEntry;
@@ -77,13 +79,13 @@ public class RecyclerActivity extends Activity {
     private static Markwon markwon(@NonNull Context context) {
         return Markwon.builder(context)
                 .usePlugin(CorePlugin.create())
-                .usePlugin(ImagesPlugin.create(plugin -> {
+//                .usePlugin(ImagesPlugin.create(plugin -> {
-                    plugin
+//                    plugin
-                            .addSchemeHandler(FileSchemeHandler.createWithAssets(context.getAssets()))
+//                            .addSchemeHandler(FileSchemeHandler.createWithAssets(context))
-                            .addSchemeHandler(OkHttpNetworkSchemeHandler.create())
+//                            .addSchemeHandler(OkHttpNetworkSchemeHandler.create())
-                            .addMediaDecoder(SvgMediaDecoder.create())
+//                            .addMediaDecoder(SvgMediaDecoder.create());
-                            .defaultMediaDecoder(DefaultImageMediaDecoder.create());
+//                }))
-                }))
+                .usePlugin(PicassoImagesPlugin.create(context))
                 // important to use TableEntryPlugin instead of TablePlugin
                 .usePlugin(TableEntryPlugin.create(context))
                 .usePlugin(HtmlPlugin.create())

settings.gradle

@@ -7,6 +7,7 @@ include ':app', ':sample',
         ':markwon-ext-tasklist',
         ':markwon-html',
         ':markwon-image',
+        ':markwon-image-picasso',
         ':markwon-recycler',
         ':markwon-recycler-table',
         ':markwon-syntax-highlight',