From 4872a6ad7f39321c1d838f253e6df8ffb77c3f0d Mon Sep 17 00:00:00 2001
From: Rachel Fenichel <fenichel@google.com>
Date: Mon, 23 Jan 2017 17:21:48 -0800
Subject: [PATCH] Enable custom flyout categories.

---
 core/constants.js     | 16 ++++++++++++++++
 core/flyout.js        | 15 +++++++--------
 core/procedures.js    |  6 +-----
 core/variables.js     |  6 +-----
 core/workspace_svg.js | 37 +++++++++++++++++++++++++++++++++++++
 5 files changed, 62 insertions(+), 18 deletions(-)

diff --git a/core/constants.js b/core/constants.js
index 5805229bf..ef828d11d 100644
--- a/core/constants.js
+++ b/core/constants.js
@@ -214,3 +214,19 @@ Blockly.DELETE_AREA_TRASH = 1;
  * @const
  */
 Blockly.DELETE_AREA_TOOLBOX = 2;
+
+/**
+ * String for use in the "custom" attribute of a category in toolbox xml.
+ * This string indicates that the category should be dynamically populated with
+ * variable blocks.
+ * @const
+ */
+Blockly.VARIABLE_CATEGORY_NAME = 'VARIABLE';
+
+/**
+ * String for use in the "custom" attribute of a category in toolbox xml.
+ * This string indicates that the category should be dynamically populated with
+ * procedure blocks.
+ * @const
+ */
+Blockly.PROCEDURE_CATEGORY_NAME = 'PROCEDURE';
diff --git a/core/flyout.js b/core/flyout.js
index 0a17a02c2..496a4035d 100644
--- a/core/flyout.js
+++ b/core/flyout.js
@@ -726,14 +726,13 @@ Blockly.Flyout.prototype.show = function(xmlList) {
   this.hide();
   this.clearOldBlocks_();
 
-  if (xmlList == Blockly.Variables.NAME_TYPE) {
-    // Special category for variables.
-    xmlList =
-        Blockly.Variables.flyoutCategory(this.workspace_.targetWorkspace);
-  } else if (xmlList == Blockly.Procedures.NAME_TYPE) {
-    // Special category for procedures.
-    xmlList =
-        Blockly.Procedures.flyoutCategory(this.workspace_.targetWorkspace);
+  // Handle dynamic categories, represented by a name instead of a list of XML.
+  // Look up the correct category generation function and call that to get a
+  // valid XML list.
+  if (typeof xmlList == 'string') {
+    var fnToApply = this.workspace_.targetWorkspace.getToolboxCategoryCallback(
+        xmlList);
+    xmlList = fnToApply(this.workspace_.targetWorkspace);
   }
 
   this.setVisible(true);
diff --git a/core/procedures.js b/core/procedures.js
index 6b5fcf60b..39119dc12 100644
--- a/core/procedures.js
+++ b/core/procedures.js
@@ -27,16 +27,12 @@
 goog.provide('Blockly.Procedures');
 
 goog.require('Blockly.Blocks');
+goog.require('Blockly.constants');
 goog.require('Blockly.Field');
 goog.require('Blockly.Names');
 goog.require('Blockly.Workspace');
 
 
-/**
- * Category to separate procedure names from variables and generated functions.
- */
-Blockly.Procedures.NAME_TYPE = 'PROCEDURE';
-
 /**
  * Find all user-created procedure definitions in a workspace.
  * @param {!Blockly.Workspace} root Root workspace.
diff --git a/core/variables.js b/core/variables.js
index 8eec06df4..45f488187 100644
--- a/core/variables.js
+++ b/core/variables.js
@@ -27,15 +27,11 @@
 goog.provide('Blockly.Variables');
 
 goog.require('Blockly.Blocks');
+goog.require('Blockly.constants');
 goog.require('Blockly.Workspace');
 goog.require('goog.string');
 
 
-/**
- * Category to separate variable names from procedures and generated functions.
- */
-Blockly.Variables.NAME_TYPE = 'VARIABLE';
-
 /**
  * Find all user-created variables that are in use in the workspace.
  * For use by generators.
diff --git a/core/workspace_svg.js b/core/workspace_svg.js
index 38a7e747d..04158f680 100644
--- a/core/workspace_svg.js
+++ b/core/workspace_svg.js
@@ -89,6 +89,11 @@ Blockly.WorkspaceSvg = function(options, opt_blockDragSurface, opt_wsDragSurface
    * @private
    */
   this.highlightedBlocks_ = [];
+
+  this.registerToolboxCategoryCallback(Blockly.VARIABLE_CATEGORY_NAME,
+      Blockly.Variables.flyoutCategory);
+  this.registerToolboxCategoryCallback(Blockly.PROCEDURE_CATEGORY_NAME,
+      Blockly.Procedures.flyoutCategory);
 };
 goog.inherits(Blockly.WorkspaceSvg, Blockly.Workspace);
 
@@ -242,6 +247,14 @@ Blockly.WorkspaceSvg.prototype.lastRecordedPageScroll_ = null;
  */
 Blockly.WorkspaceSvg.prototype.flyoutButtonCallbacks_ = {};
 
+/**
+ * Map from function names to callbacks, for deciding what to do when a custom
+ * toolbox category is opened.
+ * @type {!Object<string, function(!Blockly.Workspace):!Array<!Element>>}
+ * @private
+ */
+Blockly.WorkspaceSvg.prototype.toolboxCategoryCallbacks_ = {};
+
 /**
  * Inverted screen CTM, for use in mouseToSvg.
  * @type {SVGMatrix}
@@ -1666,6 +1679,30 @@ Blockly.WorkspaceSvg.prototype.getButtonCallback = function(key) {
   return this.flyoutButtonCallbacks_[key];
 };
 
+/**
+ * Register a callback function associated with a given key, for populating
+ * custom toolbox categories in this workspace.  See the variable and procedure
+ * categories as an example.
+ * @param {string} key The name to use to look up this function.
+ * @param {function(!Blockly.Workspace):!Array<!Element>} func The function to
+ *     call when the given toolbox category is opened.
+ */
+Blockly.WorkspaceSvg.prototype.registerToolboxCategoryCallback = function(key,
+    func) {
+  this.toolboxCategoryCallbacks_[key] = func;
+};
+
+/**
+ * Get the callback function associated with a given key, for populating
+ * custom toolbox categories in this workspace.
+ * @param {string} key The name to use to look up the function.
+ * @return {function(!Blockly.Workspace):!Array<!Element>} The function
+ *     corresponding to the given key for this workspace.
+ */
+Blockly.WorkspaceSvg.prototype.getToolboxCategoryCallback = function(key) {
+  return this.toolboxCategoryCallbacks_[key];
+};
+
 // Export symbols that would otherwise be renamed by Closure compiler.
 Blockly.WorkspaceSvg.prototype['setVisible'] =
     Blockly.WorkspaceSvg.prototype.setVisible;