From d3b8b780355f4a6d1faafe4bb4dbb1bd47d9af77 Mon Sep 17 00:00:00 2001
From: Monica Kozbial <kozbial@google.com>
Date: Fri, 10 Jul 2020 13:23:08 -0700
Subject: [PATCH] Update click event handling for workspace and trashcan.
 (#4024)

* Update click event handling for workspace and trashcan.

* Fix typo

* Change event name for trashcan flyout open
---
 core/gesture.js  |  4 ++--
 core/trashcan.js | 41 ++++++++++++++++++++++++++++++++++++++---
 2 files changed, 40 insertions(+), 5 deletions(-)

diff --git a/core/gesture.js b/core/gesture.js
index 190827de7..a5a4cd2ec 100644
--- a/core/gesture.js
+++ b/core/gesture.js
@@ -662,7 +662,7 @@ Blockly.Gesture.prototype.handleWsStart = function(e, ws) {
  * @private
  */
 Blockly.Gesture.prototype.fireWorkspaceClick_ = function(ws) {
-  var clickEvent = new Blockly.Events.Ui(null, 'workspaceClick', null, null);
+  var clickEvent = new Blockly.Events.Ui(null, 'click', null, 'workspace');
   clickEvent.workspaceId = ws.id;
   Blockly.Events.fire(clickEvent);
 };
@@ -752,7 +752,7 @@ Blockly.Gesture.prototype.doBlockClick_ = function() {
   } else {
     // Clicks events are on the start block, even if it was a shadow.
     Blockly.Events.fire(
-        new Blockly.Events.Ui(this.startBlock_, 'click', undefined, undefined));
+        new Blockly.Events.Ui(this.startBlock_, 'click', undefined, 'block'));
   }
   this.bringBlockToFront_();
   Blockly.Events.setGroup(false);
diff --git a/core/trashcan.js b/core/trashcan.js
index 107b9d602..fcb2acc0c 100644
--- a/core/trashcan.js
+++ b/core/trashcan.js
@@ -301,6 +301,8 @@ Blockly.Trashcan.prototype.createDom = function() {
   this.svgLid_.setAttributeNS(Blockly.utils.dom.XLINK_NS, 'xlink:href',
       this.workspace_.options.pathToMedia + Blockly.SPRITE.url);
 
+  Blockly.bindEventWithChecks_(
+      this.svgGroup_, 'mousedown', this, this.blockMouseDownWhenFull_);
   Blockly.bindEventWithChecks_(this.svgGroup_, 'mouseup', this, this.click);
   // bindEventWithChecks_ quashes events too aggressively. See:
   // https://groups.google.com/forum/#!topic/blockly/QF4yB9Wx00s
@@ -345,6 +347,15 @@ Blockly.Trashcan.prototype.dispose = function() {
   clearTimeout(this.lidTask_);
 };
 
+/**
+ * Whether the trashcan has contents.
+ * @return {boolean} True if the trashcan has contents.
+ * @private
+ */
+Blockly.Trashcan.prototype.hasContents_ = function() {
+  return !!this.contents_.length;
+};
+
 /**
  * Returns true if the trashcan contents-flyout is currently open.
  * @return {boolean} True if the trashcan contents-flyout is currently open.
@@ -358,7 +369,7 @@ Blockly.Trashcan.prototype.contentsIsOpen = function() {
  * it will be closed.
  */
 Blockly.Trashcan.prototype.emptyContents = function() {
-  if (!this.contents_.length) {
+  if (!this.hasContents_()) {
     return;
   }
   this.contents_.length = 0;
@@ -501,7 +512,7 @@ Blockly.Trashcan.prototype.close = function() {
  * Inspect the contents of the trash.
  */
 Blockly.Trashcan.prototype.click = function() {
-  if (!this.contents_.length) {
+  if (!this.hasContents_()) {
     return;
   }
 
@@ -510,14 +521,38 @@ Blockly.Trashcan.prototype.click = function() {
     xml[i] = Blockly.Xml.textToDom(text);
   }
   this.flyout.show(xml);
+
+  this.fireUiEvent_();
 };
 
+/**
+ * Fires a ui event for trashcan flyout opening.
+ * @private
+ */
+Blockly.Trashcan.prototype.fireUiEvent_ = function() {
+  var uiEvent = new Blockly.Events.Ui(null, 'trashcanOpen', null, true);
+  uiEvent.workspaceId = this.workspace_.id;
+  Blockly.Events.fire(uiEvent);
+};
+
+/**
+ * Prevents a workspace scroll and click event if the trashcan has blocks.
+ * @param {!Event} e A mouse down event.
+ * @private
+ */
+Blockly.Trashcan.prototype.blockMouseDownWhenFull_ = function(e) {
+  if (this.hasContents_()) {
+    e.stopPropagation();  // Don't start a workspace scroll.
+  }
+};
+
+
 /**
  * Indicate that the trashcan can be clicked (by opening it) if it has blocks.
  * @private
  */
 Blockly.Trashcan.prototype.mouseOver_ = function() {
-  if (this.contents_.length) {
+  if (this.hasContents_()) {
     this.setOpen(true);
   }
 };