[cc] Initial checkin of cc-frame-viewer

tools/cc-frame-viewer/src/ui/list_view.js

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+'use strict';
+
+/**
+ * @fileoverview Simple list view.
+ */
+base.require('ui');
+base.requireStylesheet('ui.list_view');
+base.exportTo('ui', function() {
+
+  /**
+   * @constructor
+   */
+  var ListView = ui.define('x-list-view');
+
+  ListView.prototype = {
+    __proto__: HTMLUnknownElement.prototype,
+
+    decorate: function() {
+      this.onItemClicked_ = this.onItemClicked_.bind(this);
+      this.onKeyDown_ = this.onKeyDown_.bind(this);
+      this.observer_ = new WebKitMutationObserver(this.didMutate_.bind(this));
+      this.observer_.observe(this, { childList: true });
+      this.tabIndex = 0;
+      this.addEventListener('keydown', this.onKeyDown_);
+    },
+
+    appendChild: function(x) {
+      HTMLUnknownElement.prototype.appendChild.call(this, x);
+      this.didMutate_(this.observer_.takeRecords());
+    },
+
+    insertBefore: function(x, y) {
+      HTMLUnknownElement.prototype.insertBefore.call(this, x, y);
+      this.didMutate_(this.observer_.takeRecords());
+    },
+
+    removeChild: function(x) {
+      HTMLUnknownElement.prototype.removeChild.call(this, x);
+      this.didMutate_(this.observer_.takeRecords());
+    },
+
+    replaceChild: function(x, y) {
+      HTMLUnknownElement.prototype.replaceChild.call(this, x, y);
+      this.didMutate_(this.observer_.takeRecords());
+    },
+
+    didMutate_: function(records) {
+      var selectionChanged = false;
+      for (var i = 0; i < records.length; i++) {
+        var addedNodes = records[i].addedNodes;
+        if (addedNodes) {
+          for (var j = 0; j < addedNodes.length; j++)
+            this.decorateItem_(addedNodes[j]);
+        }
+        var removedNodes = records[i].removedNodes;
+        if (removedNodes) {
+          for (var j = 0; j < removedNodes.length; j++) {
+            selectionChanged |= removedNodes[j].selected;
+            this.undecorateItem_(removedNodes[j]);
+          }
+        }
+      }
+      if (selectionChanged)
+        base.dispatchSimpleEvent(this, 'selection-changed', false);
+    },
+
+    decorateItem_: function(item) {
+      item.classList.add('list-item');
+      item.addEventListener('click', this.onItemClicked_);
+
+      var listView = this;
+      Object.defineProperty(
+        item,
+        "selected", {
+          configurable: true,
+          set: function(value) {
+            var oldSelection = listView.selectedElement;
+            if (oldSelection && oldSelection != this && value)
+              listView.selectedElement.removeAttribute('selected');
+            if (value)
+              this.setAttribute('selected', 'selected');
+            else
+              this.removeAttribute('selected');
+            var newSelection = listView.selectedElement;
+            if (newSelection != oldSelection)
+              base.dispatchSimpleEvent(listView, 'selection-changed', false);
+          },
+          get: function() {
+            return this.hasAttribute('selected');
+          }
+        });
+    },
+
+    undecorateItem_: function(item) {
+      item.classList.remove('list-item');
+      item.removeEventListener('click', this.onItemClicked_);
+      delete item.selected;
+    },
+
+    get selectedElement() {
+      var el = this.querySelector('.list-item[selected]');
+      if (!el)
+        return undefined;
+      return el;
+    },
+
+    set selectedElement(el) {
+      if (!el) {
+        if (this.selectedElement)
+          this.selectedElement.selected = false;
+        return;
+      }
+
+      if (el.parentElement != this)
+        throw new Error(
+            'Can only select elements that are children of this list view');
+      el.selected = true;
+    },
+
+    clear: function() {
+      var changed = this.selectedElement !== undefined;
+      this.textContent = '';
+      if (changed)
+        base.dispatchSimpleEvent(this, 'selection-changed', false);
+    },
+
+    onItemClicked_: function(e) {
+      var currentSelectedElement = this.selectedElement;
+      if (currentSelectedElement)
+        currentSelectedElement.removeAttribute('selected');
+      e.target.setAttribute('selected', 'selected');
+      base.dispatchSimpleEvent(this, 'selection-changed', false);
+    },
+
+    onKeyDown_: function(e) {
+      if (e.keyCode == 38) { // Up arrow.
+        var prev = this.selectedElement.previousSibling;
+        if (prev) {
+          prev.selected = true;
+          prev.scrollIntoView(false);
+          e.preventDefault();
+          return true;
+        }
+      } else if(e.keyCode == 40) { // Down arrow.
+        var next = this.selectedElement.nextSibling;
+        if (next) {
+          next.selected = true;
+          next.scrollIntoView(false);
+          e.preventDefault();
+          return true;
+        }
+      }
+    },
+
+    addItem: function(textContent) {
+      var item = document.createElement('div');
+      item.textContent = textContent;
+      this.appendChild(item);
+      return item;
+    },
+
+  };
+
+  return {
+    ListView: ListView
+  };
+
+});