Display images in multiline Braille

chrome/browser/resources/chromeos/chromevox/cvox2/background/command_handler.js

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview ChromeVox commands.
  */
 
 goog.provide('CommandHandler');
 
@@ skipping 560 matching lines @@
         ChromeVoxState.instance.pageSel_ = null;
         return false;
       }
       break;
     case 'fullyDescribe':
       var o = new Output();
       o.withContextFirst()
           .withRichSpeechAndBraille(current, null, Output.EventType.NAVIGATE)
           .go();
       return false;
-
+    case 'viewGraphicAsBraille':
+      // Find the first node within the current range that supports image data.
+      var imageNode = AutomationUtil.findNodePost(
+          current.start.node, Dir.FORWARD,
+          AutomationPredicate.supportsImageData);
+      if (imageNode) {
+        ChromeVoxState.instance.nodeDisplayingBrailleImage = imageNode;
+        if (imageNode.imageDataUrl) {
+          cvox.ChromeVox.braille.writeRawImage(imageNode.imageDataUrl);
+          cvox.ChromeVox.braille.freeze();
+        } else {
+          // Request image data. If it succeeds, we will get a
+          // IMAGE_FRAME_UPDATED event.
+          imageNode.getImageData(0, 0);

[David Tseng, 2017/02/24 05:39:46]

I think we should install the event handler directly on this node here so the
code to handle this isn't hidden elsewhere. Also, if we do that, you don't have
to explicitly track the node on ChromeVoxState.

[dmazzoni, 2017/02/27 06:56:24]

Done.

+        }
+      }
+      return false;
     // Table commands.
     case 'previousRow':
       dir = Dir.BACKWARD;
       var tableOpts = {row: true, dir: dir};
       pred = AutomationPredicate.makeTableCellPredicate(
           current.start.node, tableOpts);
       predErrorMsg = 'no_cell_above';
       rootPred = AutomationPredicate.table;
       break;
     case 'previousCol':
@@ skipping 176 matching lines @@
       break;
   }
   if (announcement) {
     cvox.ChromeVox.tts.speak(
         announcement, cvox.QueueMode.FLUSH,
         cvox.AbstractTts.PERSONALITY_ANNOTATION);
   }
 };
 
 }); //  goog.scope