Move bind/unbind events functions to new file, with example usage.

core/block_svg.js

@@ -16,6 +16,7 @@ goog.require('Blockly.ASTNode');
 goog.require('Blockly.Block');
 goog.require('Blockly.blockAnimations');
 goog.require('Blockly.blockRendering.IPathObject');
+goog.require('Blockly.browserEvents');
 goog.require('Blockly.constants');
 goog.require('Blockly.ContextMenu');
 goog.require('Blockly.ContextMenuRegistry');
@@ -223,7 +224,7 @@ Blockly.BlockSvg.prototype.initSvg = function() {
   this.pathObject.updateMovable(this.isMovable());
   var svg = this.getSvgRoot();
   if (!this.workspace.options.readOnly && !this.eventsInit_ && svg) {
-    Blockly.bindEventWithChecks_(
+    Blockly.browserEvents.conditionalBind(
         svg, 'mousedown', this, this.onMouseDown_);
   }
   this.eventsInit_ = true;

core/blockly.js

@@ -17,6 +17,7 @@
 goog.provide('Blockly');
 
 goog.require('Blockly.constants');
+goog.require('Blockly.browserEvents');
 goog.require('Blockly.Events');
 goog.require('Blockly.Events.Ui');
 goog.require('Blockly.Events.UiBase');
@@ -104,13 +105,6 @@ Blockly.cache3dSupported_ = null;
  */
 Blockly.parentContainer = null;
 
-/**
- * Blockly opaque event data used to unbind events when using
- * `Blockly.bindEvent_` and `Blockly.bindEventWithChecks_`.
- * @typedef {!Array.<!Array>}
- */
-Blockly.EventData;
-
 /**
  * Returns the dimensions of the specified SVG image.
  * @param {!SVGElement} svg SVG image.
@@ -388,149 +382,6 @@ Blockly.defineBlocksWithJsonArray = function(jsonArray) {
   }
 };
 
-/**
- * Bind an event to a function call.  When calling the function, verifies that
- * it belongs to the touch stream that is currently being processed, and splits
- * multitouch events into multiple events as needed.
- * @param {!EventTarget} node Node upon which to listen.
- * @param {string} name Event name to listen to (e.g. 'mousedown').
- * @param {Object} thisObject The value of 'this' in the function.
- * @param {!Function} func Function to call when event is triggered.
- * @param {boolean=} opt_noCaptureIdentifier True if triggering on this event
- *     should not block execution of other event handlers on this touch or
- *     other simultaneous touches.  False by default.
- * @param {boolean=} opt_noPreventDefault True if triggering on this event
- *     should prevent the default handler.  False by default.  If
- *     opt_noPreventDefault is provided, opt_noCaptureIdentifier must also be
- *     provided.
- * @return {!Blockly.EventData} Opaque data that can be passed to unbindEvent_.
- */
-Blockly.bindEventWithChecks_ = function(node, name, thisObject, func,
-    opt_noCaptureIdentifier, opt_noPreventDefault) {
-  var handled = false;
-  var wrapFunc = function(e) {
-    var captureIdentifier = !opt_noCaptureIdentifier;
-    // Handle each touch point separately.  If the event was a mouse event, this
-    // will hand back an array with one element, which we're fine handling.
-    var events = Blockly.Touch.splitEventByTouches(e);
-    for (var i = 0, event; (event = events[i]); i++) {
-      if (captureIdentifier && !Blockly.Touch.shouldHandleEvent(event)) {
-        continue;
-      }
-      Blockly.Touch.setClientFromTouch(event);
-      if (thisObject) {
-        func.call(thisObject, event);
-      } else {
-        func(event);
-      }
-      handled = true;
-    }
-  };
-
-  var bindData = [];
-  if (Blockly.utils.global['PointerEvent'] &&
-      (name in Blockly.Touch.TOUCH_MAP)) {
-    for (var i = 0, type; (type = Blockly.Touch.TOUCH_MAP[name][i]); i++) {
-      node.addEventListener(type, wrapFunc, false);
-      bindData.push([node, type, wrapFunc]);
-    }
-  } else {
-    node.addEventListener(name, wrapFunc, false);
-    bindData.push([node, name, wrapFunc]);
-
-    // Add equivalent touch event.
-    if (name in Blockly.Touch.TOUCH_MAP) {
-      var touchWrapFunc = function(e) {
-        wrapFunc(e);
-        // Calling preventDefault stops the browser from scrolling/zooming the
-        // page.
-        var preventDef = !opt_noPreventDefault;
-        if (handled && preventDef) {
-          e.preventDefault();
-        }
-      };
-      for (var i = 0, type; (type = Blockly.Touch.TOUCH_MAP[name][i]); i++) {
-        node.addEventListener(type, touchWrapFunc, false);
-        bindData.push([node, type, touchWrapFunc]);
-      }
-    }
-  }
-  return bindData;
-};
-
-
-/**
- * Bind an event to a function call.  Handles multitouch events by using the
- * coordinates of the first changed touch, and doesn't do any safety checks for
- * simultaneous event processing.  In most cases prefer is to use
- * `Blockly.bindEventWithChecks_`.
- * @param {!EventTarget} node Node upon which to listen.
- * @param {string} name Event name to listen to (e.g. 'mousedown').
- * @param {Object} thisObject The value of 'this' in the function.
- * @param {!Function} func Function to call when event is triggered.
- * @return {!Blockly.EventData} Opaque data that can be passed to unbindEvent_.
- */
-Blockly.bindEvent_ = function(node, name, thisObject, func) {
-  var wrapFunc = function(e) {
-    if (thisObject) {
-      func.call(thisObject, e);
-    } else {
-      func(e);
-    }
-  };
-
-  var bindData = [];
-  if (Blockly.utils.global['PointerEvent'] &&
-      (name in Blockly.Touch.TOUCH_MAP)) {
-    for (var i = 0, type; (type = Blockly.Touch.TOUCH_MAP[name][i]); i++) {
-      node.addEventListener(type, wrapFunc, false);
-      bindData.push([node, type, wrapFunc]);
-    }
-  } else {
-    node.addEventListener(name, wrapFunc, false);
-    bindData.push([node, name, wrapFunc]);
-
-    // Add equivalent touch event.
-    if (name in Blockly.Touch.TOUCH_MAP) {
-      var touchWrapFunc = function(e) {
-        // Punt on multitouch events.
-        if (e.changedTouches && e.changedTouches.length == 1) {
-          // Map the touch event's properties to the event.
-          var touchPoint = e.changedTouches[0];
-          e.clientX = touchPoint.clientX;
-          e.clientY = touchPoint.clientY;
-        }
-        wrapFunc(e);
-
-        // Stop the browser from scrolling/zooming the page.
-        e.preventDefault();
-      };
-      for (var i = 0, type; (type = Blockly.Touch.TOUCH_MAP[name][i]); i++) {
-        node.addEventListener(type, touchWrapFunc, false);
-        bindData.push([node, type, touchWrapFunc]);
-      }
-    }
-  }
-  return bindData;
-};
-
-/**
- * Unbind one or more events event from a function call.
- * @param {!Array.<!Array>} bindData Opaque data from bindEvent_.
- *     This list is emptied during the course of calling this function.
- * @return {!Function} The function call.
- */
-Blockly.unbindEvent_ = function(bindData) {
-  while (bindData.length) {
-    var bindDatum = bindData.pop();
-    var node = bindDatum[0];
-    var name = bindDatum[1];
-    var func = bindDatum[2];
-    node.removeEventListener(name, func, false);
-  }
-  return func;
-};
-
 /**
  * Is the given string a number (includes negative and decimals).
  * @param {string} str Input string.
@@ -632,3 +483,20 @@ Blockly.checkBlockColourConstant_ = function(
 Blockly.setParentContainer = function(container) {
   Blockly.parentContainer = container;
 };
+
+/** Aliases. */
+
+/**
+ * @see Blockly.browserEvents.bind
+ */
+Blockly.bindEvent_ = Blockly.browserEvents.bind;
+
+/**
+ * @see Blockly.browserEvents.unbind
+ */
+Blockly.unbindEvent_ = Blockly.browserEvents.unbind;
+
+/**
+ * @see Blockly.browserEvents.conditionalBind
+ */
+Blockly.bindEventWithChecks_ = Blockly.browserEvents.conditionalBind;

core/browser_events.js

@@ -0,0 +1,174 @@
+/**
+ * @license
+ * Copyright 2021 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview Browser event handling.
+ * @author fenichel@google.com (Rachel Fenichel)
+ */
+'use strict';
+
+goog.provide('Blockly.browserEvents');
+
+goog.require('Blockly.Touch');
+
+
+/**
+ * Blockly opaque event data used to unbind events when using
+ * `Blockly.browserEvents.bind` and
+ * `Blockly.browserEvents.conditionalBind`.
+ * @typedef {!Array.<!Array>}
+ */
+Blockly.browserEvents.Data;
+
+/**
+ * Bind an event handler that can be ignored if it is not part of the active
+ * touch stream.
+ * Use this for events that either start or continue a multi-part gesture (e.g.
+ * mousedown or mousemove, which may be part of a drag or click).
+ * @param {!EventTarget} node Node upon which to listen.
+ * @param {string} name Event name to listen to (e.g. 'mousedown').
+ * @param {Object} thisObject The value of 'this' in the function.
+ * @param {!Function} func Function to call when event is triggered.
+ * @param {boolean=} opt_noCaptureIdentifier True if triggering on this event
+ *     should not block execution of other event handlers on this touch or
+ *     other simultaneous touches.  False by default.
+ * @param {boolean=} opt_noPreventDefault True if triggering on this event
+ *     should prevent the default handler.  False by default.  If
+ *     opt_noPreventDefault is provided, opt_noCaptureIdentifier must also be
+ *     provided.
+ * @return {!Blockly.browserEvents.Data} Opaque data that can be passed to
+ *     unbindEvent_.
+ * @public
+ */
+Blockly.browserEvents.conditionalBind = function(
+    node, name, thisObject, func, opt_noCaptureIdentifier,
+    opt_noPreventDefault) {
+  var handled = false;
+  var wrapFunc = function(e) {
+    var captureIdentifier = !opt_noCaptureIdentifier;
+    // Handle each touch point separately.  If the event was a mouse event, this
+    // will hand back an array with one element, which we're fine handling.
+    var events = Blockly.Touch.splitEventByTouches(e);
+    for (var i = 0, event; (event = events[i]); i++) {
+      if (captureIdentifier && !Blockly.Touch.shouldHandleEvent(event)) {
+        continue;
+      }
+      Blockly.Touch.setClientFromTouch(event);
+      if (thisObject) {
+        func.call(thisObject, event);
+      } else {
+        func(event);
+      }
+      handled = true;
+    }
+  };
+
+  var bindData = [];
+  if (Blockly.utils.global['PointerEvent'] &&
+      (name in Blockly.Touch.TOUCH_MAP)) {
+    for (var i = 0, type; (type = Blockly.Touch.TOUCH_MAP[name][i]); i++) {
+      node.addEventListener(type, wrapFunc, false);
+      bindData.push([node, type, wrapFunc]);
+    }
+  } else {
+    node.addEventListener(name, wrapFunc, false);
+    bindData.push([node, name, wrapFunc]);
+
+    // Add equivalent touch event.
+    if (name in Blockly.Touch.TOUCH_MAP) {
+      var touchWrapFunc = function(e) {
+        wrapFunc(e);
+        // Calling preventDefault stops the browser from scrolling/zooming the
+        // page.
+        var preventDef = !opt_noPreventDefault;
+        if (handled && preventDef) {
+          e.preventDefault();
+        }
+      };
+      for (var i = 0, type; (type = Blockly.Touch.TOUCH_MAP[name][i]); i++) {
+        node.addEventListener(type, touchWrapFunc, false);
+        bindData.push([node, type, touchWrapFunc]);
+      }
+    }
+  }
+  return bindData;
+};
+
+
+/**
+ * Bind an event handler that should be called regardless of whether it is part
+ * of the active touch stream.
+ * Use this for events that are not part of a multi-part gesture (e.g.
+ * mouseover for tooltips).
+ * @param {!EventTarget} node Node upon which to listen.
+ * @param {string} name Event name to listen to (e.g. 'mousedown').
+ * @param {Object} thisObject The value of 'this' in the function.
+ * @param {!Function} func Function to call when event is triggered.
+ * @return {!Blockly.browserEvents.Data} Opaque data that can be passed to
+ *     unbindEvent_.
+ * @public
+ */
+Blockly.browserEvents.bind = function(node, name, thisObject, func) {
+  var wrapFunc = function(e) {
+    if (thisObject) {
+      func.call(thisObject, e);
+    } else {
+      func(e);
+    }
+  };
+
+  var bindData = [];
+  if (Blockly.utils.global['PointerEvent'] &&
+      (name in Blockly.Touch.TOUCH_MAP)) {
+    for (var i = 0, type; (type = Blockly.Touch.TOUCH_MAP[name][i]); i++) {
+      node.addEventListener(type, wrapFunc, false);
+      bindData.push([node, type, wrapFunc]);
+    }
+  } else {
+    node.addEventListener(name, wrapFunc, false);
+    bindData.push([node, name, wrapFunc]);
+
+    // Add equivalent touch event.
+    if (name in Blockly.Touch.TOUCH_MAP) {
+      var touchWrapFunc = function(e) {
+        // Punt on multitouch events.
+        if (e.changedTouches && e.changedTouches.length == 1) {
+          // Map the touch event's properties to the event.
+          var touchPoint = e.changedTouches[0];
+          e.clientX = touchPoint.clientX;
+          e.clientY = touchPoint.clientY;
+        }
+        wrapFunc(e);
+
+        // Stop the browser from scrolling/zooming the page.
+        e.preventDefault();
+      };
+      for (var i = 0, type; (type = Blockly.Touch.TOUCH_MAP[name][i]); i++) {
+        node.addEventListener(type, touchWrapFunc, false);
+        bindData.push([node, type, touchWrapFunc]);
+      }
+    }
+  }
+  return bindData;
+};
+
+/**
+ * Unbind one or more events event from a function call.
+ * @param {!Blockly.browserEvents.Data} bindData Opaque data from bindEvent_.
+ *     This list is emptied during the course of calling this function.
+ * @return {!Function} The function call.
+ * @public
+ */
+Blockly.browserEvents.unbind = function(bindData) {
+  while (bindData.length) {
+    var bindDatum = bindData.pop();
+    var node = bindDatum[0];
+    var name = bindDatum[1];
+    var func = bindDatum[2];
+    node.removeEventListener(name, func, false);
+  }
+  return func;
+};