Decode/start GIFs on Android 9+

FAQ.md

@@ -55,12 +55,12 @@ For authorizing:
 * ~~More compact folder view~~
 * ~~Compose lists and tables~~ (this requires a rich text editor, see [this FAQ](#user-content-faq99))
 * ~~Pinch zoom text size~~
+* ~~Display GIFs~~
 * Send as attachment
 * Themes
 * Search for settings
 * Select any day for time conditions
 * Widget for selected account
-* Display GIFs
 
 Anything on this list is in random order and *might* be added in the near future.
 

app/src/main/java/eu/faircode/email/AdapterMessage.java

@@ -38,6 +38,7 @@ import android.database.Cursor;
 import android.graphics.Color;
 import android.graphics.Rect;
 import android.graphics.Typeface;
+import android.graphics.drawable.AnimatedImageDrawable;
 import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.os.Build;
@@ -2515,7 +2516,14 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                 Spanned spanned = HtmlHelper.fromHtml(html, new Html.ImageGetter() {
                     @Override
                     public Drawable getDrawable(String source) {
-                        return HtmlHelper.decodeImage(context, message.id, source, show_images, tvBody);
+                        Drawable drawable = HtmlHelper.decodeImage(context, message.id, source, show_images, tvBody);
+
+                        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
+                            if (drawable instanceof AnimatedImageDrawable)
+                                ((AnimatedImageDrawable) drawable).start();
+                        }
+
+                        return drawable;
                     }
                 }, null);
 
@@ -3777,6 +3785,10 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                 @Override
                 protected void onExecuted(Bundle args, Drawable drawable) {
                     pv.setImageDrawable(drawable);
+                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
+                        if (drawable instanceof AnimatedImageDrawable)
+                            ((AnimatedImageDrawable) drawable).start();
+                    }
                 }
 
                 @Override

app/src/main/java/eu/faircode/email/HtmlHelper.java

@@ -24,10 +24,12 @@ import android.content.SharedPreferences;
 import android.content.res.Resources;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
+import android.graphics.ImageDecoder;
 import android.graphics.Rect;
 import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
 import android.graphics.drawable.LevelListDrawable;
+import android.os.Build;
 import android.os.Handler;
 import android.text.Html;
 import android.text.SpannableStringBuilder;
@@ -412,8 +414,41 @@ public class HtmlHelper {
                 d.setBounds(0, 0, px, px);
                 return d;
             } else {
-                Bitmap bm = Helper.decodeImage(attachment.getFile(context),
-                        res.getDisplayMetrics().widthPixels);
+                int scaleToPixels = res.getDisplayMetrics().widthPixels;
+                if ("image/gif".equals(attachment.type) &&
+                        Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
+                    ImageDecoder.Source isource = ImageDecoder.createSource(attachment.getFile(context));
+                    Drawable gif;
+                    try {
+                        gif = ImageDecoder.decodeDrawable(isource, new ImageDecoder.OnHeaderDecodedListener() {
+                            @Override
+                            public void onHeaderDecoded(
+                                    @NonNull ImageDecoder decoder,
+                                    @NonNull ImageDecoder.ImageInfo info,
+                                    @NonNull ImageDecoder.Source source) {
+                                int factor = 1;
+                                while (info.getSize().getWidth() / factor > scaleToPixels)
+                                    factor *= 2;
+
+                                decoder.setTargetSampleSize(factor);
+                            }
+                        });
+                    } catch (IOException ex) {
+                        Log.w(ex);
+                        gif = null;
+                    }
+                    if (gif == null) {
+                        Log.i("GIF not decodable CID=" + cid);
+                        Drawable d = res.getDrawable(R.drawable.baseline_broken_image_24, theme);
+                        d.setBounds(0, 0, px, px);
+                        return d;
+                    } else {
+                        if (view != null)
+                            fitDrawable(gif, a, view);
+                        return gif;
+                    }
+                } else {
+                    Bitmap bm = Helper.decodeImage(attachment.getFile(context), scaleToPixels);
                     if (bm == null) {
                         Log.i("Image not decodable CID=" + cid);
                         Drawable d = res.getDrawable(R.drawable.baseline_broken_image_24, theme);
@@ -429,6 +464,7 @@ public class HtmlHelper {
                     }
                 }
             }
+        }
 
         // Data URI
         if (data && (show || inline))