Improved image caching

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

@@ -1882,7 +1882,7 @@ public class FragmentCompose extends FragmentBase {
         new SimpleTask<Spanned>() {
             @Override
             protected Spanned onExecute(Context context, Bundle args) throws IOException {
-                long id = args.getLong("id");
+                final long id = args.getLong("id");
                 List<Uri> uris = args.getParcelableArrayList("uris");
                 boolean image = args.getBoolean("image");
                 int resize = args.getInt("resize");
@@ -2637,7 +2637,7 @@ public class FragmentCompose extends FragmentBase {
         Spanned spanned = HtmlHelper.fromHtml(text, new Html.ImageGetter() {
             @Override
             public Drawable getDrawable(String source) {
-                return ImageHelper.decodeImage(getContext(), -1, source, true, 0, etBody);
+                return ImageHelper.decodeImage(getContext(), working, source, true, 0, etBody);
             }
         }, null);
         etBody.getText().insert(etBody.getSelectionStart(), spanned);
@@ -4572,7 +4572,7 @@ public class FragmentCompose extends FragmentBase {
                 signature = HtmlHelper.fromHtml(identity.signature, new Html.ImageGetter() {
                     @Override
                     public Drawable getDrawable(String source) {
-                        return ImageHelper.decodeImage(getContext(), -1, source, true, 0, tvSignature);
+                        return ImageHelper.decodeImage(getContext(), working, source, true, 0, tvSignature);
                     }
                 }, null);
             tvSignature.setText(signature);

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

@@ -333,7 +333,7 @@ class ImageHelper {
                 return d;
             }
 
-            if (!show || id < 0) {
+            if (!show) {
                 // Show placeholder icon
                 int resid = (embedded || data ? R.drawable.baseline_photo_library_24 : R.drawable.baseline_image_24);
                 Drawable d = res.getDrawable(resid, theme);
@@ -513,6 +513,9 @@ class ImageHelper {
     }
 
     private static Drawable getCachedImage(Context context, long id, String source) {
+        if (id < 0)
+            return null;
+
         File file = getCacheFile(context, id, source);
         if (file.exists()) {
             Log.i("Using cached " + file);
@@ -618,10 +621,12 @@ class ImageHelper {
 
         Log.i("Downloaded image source=" + source);
 
+        if (id >= 0) {
             File file = getCacheFile(context, id, source);
             try (OutputStream os = new BufferedOutputStream(new FileOutputStream(file))) {
                 bm.compress(Bitmap.CompressFormat.PNG, 90, os);
             }
+        }
 
         Drawable d = new BitmapDrawable(res, bm);
         d.setBounds(0, 0, Math.round(bm.getWidth() * dm.density), Math.round(bm.getHeight() * dm.density));