Add menu option to hide workspace controls

appinventor/blocklyeditor/src/msg/en/_messages.js

@@ -44,6 +44,8 @@ Blockly.Msg.en.switch_language_to_english = {
     Blockly.Msg.UNDO = 'Undo';
     Blockly.Msg.REDO = 'Redo';
     Blockly.Msg.CLEAN_UP = 'Clean up Blocks';
+    Blockly.Msg.HIDE = 'Hide Workspace Controls';
+    Blockly.Msg.SHOW = 'Show Workspace Controls';
     Blockly.Msg.DUPLICATE_BLOCK = 'Duplicate';
     Blockly.Msg.REMOVE_COMMENT = 'Remove Comment';
     Blockly.Msg.ADD_COMMENT = 'Add Comment';

appinventor/blocklyeditor/src/workspace_svg.js

@@ -63,6 +63,12 @@ Blockly.WorkspaceSvg.prototype.blocksNeedingRendering = null;
  */
 Blockly.WorkspaceSvg.prototype.latestClick = { x: 0, y: 0 };
 
+/** 
+ * Whether the workspace elements are hidden
+ * @type {boolean}
+ */
+Blockly.WorkspaceSvg.prototype.chromeHidden = false;
+
 /**
  * Wrap the onMouseClick_ event to handle additional behaviors.
  */
@@ -568,6 +574,19 @@ Blockly.WorkspaceSvg.prototype.customContextMenu = function(menuOptions) {
   };
   menuOptions.splice(3, 0, exportOption);
 
+  //Show or hide workspace SVG elements backpack, zoom, and trashcan
+  var workspaceOption = {enabled: true};
+  workspaceOption.text = this.chromeHidden ? Blockly.Msg.SHOW : Blockly.Msg.HIDE;
+  var displayStyle = this.chromeHidden ? 'block' : 'none';
+  workspaceOption.callback= function() {
+    self.backpack_.svgGroup_.style.display=displayStyle;
+    self.trashcan.svgGroup_.style.display=displayStyle;
+    self.zoomControls_.svgGroup_.style.display=displayStyle;
+    self.warningIndicator_.svgGroup_.style.display=displayStyle;
+    self.chromeHidden = !self.chromeHidden;
+  };
+  menuOptions.push(workspaceOption);
+
   // Arrange blocks in row order.
   var arrangeOptionH = {enabled: (Blockly.workspace_arranged_position !== Blockly.BLKS_HORIZONTAL)};
   arrangeOptionH.text = Blockly.Msg.ARRANGE_H;