much faster removeAll(), single event trigger

* `removeAll()` is now much faster as it doesn't cause any relayout (added GridStackEngine.removeAll to optimize)
* it now calls `removed` event back just once with a list of nodes
* _removedNodes uses actualy nodes (not clones)

better fix than #551, related to previous #1096

Author: Alain Dumesny

demo/responsive.html

@@ -85,9 +85,9 @@ <h1>Responsive grid demo</h1>
         this.grid = $('.grid-stack').data('gridstack');
 
         this.loadGrid = function () {
-          this.grid.batchUpdate();
           this.grid.removeAll();
           var items = GridStackUI.Utils.sort(this.serializedData);
+          this.grid.batchUpdate();
           items.forEach(function (node, i) {
             this.grid.addWidget($('<div><div class="grid-stack-item-content">' + i + '</div></div>'), node);
           }.bind(this));

demo/serialization.html

@@ -56,9 +56,9 @@ <h1>Serialization demo</h1>
         this.grid = $('.grid-stack').data('gridstack');
 
         this.loadGrid = function () {
-          this.grid.batchUpdate();
           this.grid.removeAll();
           var items = GridStackUI.Utils.sort(this.serializedData);
+          this.grid.batchUpdate();
           items.forEach(function (node) {
             this.grid.addWidget($('<div><div class="grid-stack-item-content"></div></div>'), node);
           }, this);

doc/CHANGES.md

@@ -32,6 +32,7 @@ Change log
 - fixed callbacks to get either `added, removed, change` or combination if adding a node require also to change its (x,y) for example.
 Also you can now call `batchUpdate()` before calling a bunch of `addWidget()` and get a single event callback (more efficient).
 [#1096](https://github.com/gridstack/gridstack.js/pull/1096)
+- `removeAll()` is now much faster (no relayout) and calls `removed` event just once with a list
 
 ## v0.5.5 (2019-11-27)
 

spec/e2e/html/gridstack-with-height.html

@@ -35,10 +35,10 @@ <h1>gridstack.js tests</h1>
         ];
 
         this.grid = $('.grid-stack').data('gridstack');
-        this.grid.batchUpdate();
         this.grid.removeAll();
         items = GridStackUI.Utils.sort(items);
         var id = 0;
+        this.grid.batchUpdate();
         items.forEach(function(node) {
           var w = $('<div><div class="grid-stack-item-content"></div></div>');
           w.attr('id', 'item-' + (++id));

spec/gridstack-spec.js

@@ -7,10 +7,10 @@ describe('gridstack', function() {
   var gridstackHTML =
     '<div style="width: 992px; height: 800px" id="gs-cont">' +
     '  <div class="grid-stack">' +
-    '    <div class="grid-stack-item" data-gs-x="0" data-gs-y="0" data-gs-width="4" data-gs-height="2">' +
+    '    <div class="grid-stack-item" data-gs-x="0" data-gs-y="0" data-gs-width="4" data-gs-height="2" id="item1">' +
     '      <div class="grid-stack-item-content"></div>' +
     '    </div>' +
-    '    <div class="grid-stack-item" data-gs-x="4" data-gs-y="0" data-gs-width="4" data-gs-height="4">' +
+    '    <div class="grid-stack-item" data-gs-x="4" data-gs-y="0" data-gs-width="4" data-gs-height="4" id="item2">' +
     '      <div class="grid-stack-item-content"></div>' +
     '    </div>' +
     '  </div>' +
@@ -457,6 +457,36 @@ describe('gridstack', function() {
     });
   });
 
+  describe('grid.removeAll', function() {
+    beforeEach(function() {
+      document.body.insertAdjacentHTML('afterbegin', gridstackHTML);
+    });
+    afterEach(function() {
+      document.body.removeChild(document.getElementById('gs-cont'));
+    });
+    it('should remove all children by default', function() {
+      $('.grid-stack').gridstack();
+      var grid = $('.grid-stack').data('gridstack');
+      grid.removeAll();
+      expect(grid.grid.nodes).toEqual([]);
+      expect(document.getElementById('item1')).toBe(null);
+    });
+    it('should remove all children', function() {
+      $('.grid-stack').gridstack();
+      var grid = $('.grid-stack').data('gridstack');
+      grid.removeAll(true);
+      expect(grid.grid.nodes).toEqual([]);
+      expect(document.getElementById('item1')).toBe(null);
+    });
+    it('should remove gridstack part, leave DOM behind', function() {
+      $('.grid-stack').gridstack();
+      var grid = $('.grid-stack').data('gridstack');
+      grid.removeAll(false);
+      expect(grid.grid.nodes).toEqual([]);
+      expect(document.getElementById('item1')).not.toBe(null);
+    });
+  });
+
   describe('grid method obsolete warnings', function() {
     beforeEach(function() {
       document.body.insertAdjacentHTML('afterbegin', gridstackHTML);

src/gridstack.js

@@ -460,8 +460,8 @@
   GridStackEngine.prototype._notify = function() {
     if (this._batchMode) { return; }
     var args = Array.prototype.slice.call(arguments, 0);
-    args[0] = args[0] === undefined ? [] : [args[0]];
-    args[1] = args[1] === undefined ? true : args[1];
+    args[0] = (args[0] === undefined ? [] : (Array.isArray(args[0]) ? args[0] : [args[0]]) );
+    args[1] = (args[1] === undefined ? true : args[1]);
     var dirtyNodes = args[0].concat(this.getDirtyNodes());
     this.onchange(dirtyNodes, args[1]);
   };
@@ -516,14 +516,23 @@
   };
 
   GridStackEngine.prototype.removeNode = function(node, detachNode) {
-    detachNode = detachNode === undefined ? true : detachNode;
-    this._removedNodes.push(Utils.clone(node));
+    detachNode = (detachNode === undefined ? true : detachNode);
+    this._removedNodes.push(node);
     node._id = null;
     this.nodes = Utils.without(this.nodes, node);
     this._packNodes();
     this._notify(node, detachNode);
   };
 
+  GridStackEngine.prototype.removeAll = function(detachNode) {
+    if (this.nodes.length === 0) { return; }
+    detachNode = (detachNode === undefined ? true : detachNode);
+    this.nodes.forEach(function(n) { n._id = null; }); // hint that node is being removed
+    this._removedNodes = this.nodes;
+    this.nodes = [];
+    this._notify(this._removedNodes, detachNode);
+  };
+
   GridStackEngine.prototype.canMoveNode = function(node, x, y, width, height) {
     if (!this.isNodeChangedPosition(node, x, y, width, height)) {
       return false;
@@ -764,7 +773,7 @@
     this._initStyles();
 
     this.grid = new GridStackEngine(this.opts.column, function(nodes, detachNode) {
-      detachNode = detachNode === undefined ? true : detachNode;
+      detachNode = (detachNode === undefined ? true : detachNode);
       var maxHeight = 0;
       this.nodes.forEach(function(n) {
         maxHeight = Math.max(maxHeight, n.y + n.height);
@@ -1475,31 +1484,27 @@
   };
 
   GridStack.prototype.removeWidget = function(el, detachNode) {
-    detachNode = detachNode === undefined ? true : detachNode;
+    detachNode = (detachNode === undefined ? true : detachNode);
     el = $(el);
     var node = el.data('_gridstack_node');
-
     // For Meteor support: https://github.com/gridstack/gridstack.js/pull/272
     if (!node) {
       node = this.grid.getNodeDataByDOMEl(el);
     }
 
-    this.grid.removeNode(node, detachNode);
     el.removeData('_gridstack_node');
-    this._updateContainerHeight();
-    if (detachNode) {
-      el.remove();
-    }
+    this.grid.removeNode(node, detachNode);
     this._triggerRemoveEvent();
     // this._triggerChangeEvent(true); already have removeEvent
   };
 
   GridStack.prototype.removeAll = function(detachNode) {
+    // remove our data structure before list gets emptied (in case detachNode is false)
     this.grid.nodes.forEach(function(node) {
-      this.removeWidget(node.el, detachNode);
-    }, this);
-    this.grid.nodes = [];
-    this._updateContainerHeight();
+      node.el.removeData('_gridstack_node');
+    });
+    this.grid.removeAll(detachNode);
+    this._triggerRemoveEvent();
   };
 
   GridStack.prototype.destroy = function(detachGrid) {
@@ -1761,7 +1766,6 @@
 
   GridStack.prototype.commit = function() {
     this.grid.commit();
-    this._updateContainerHeight();
     this._triggerRemoveEvent();
     this._triggerAddEvent();
     this._triggerChangeEvent();