The Tor Browser: comparison browser/devtools/shared/widgets/FastListWidget.js

comparison: browser/devtools/shared/widgets/FastListWidget.js

browser/devtools/shared/widgets/FastListWidget.js

branch: TOR_BUG_9701
changeset 15: b8a032363ba2

equal deleted inserted replaced

--1:000000000000
+:901b86a7e940
+/* -*- Mode: javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ft=javascript ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+* License, v. 2.0. If a copy of the MPL was not distributed with this
+* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+"use strict";
+const EventEmitter = require("devtools/toolkit/event-emitter");
+const { Cu, Ci } = require("chrome");
+const { ViewHelpers } = Cu.import("resource:///modules/devtools/ViewHelpers.jsm", {});
+/**
+* A list menu widget that attempts to be very fast.
+*
+* Note: this widget should be used in tandem with the WidgetMethods in
+* ViewHelpers.jsm.
+*
+* @param nsIDOMNode aNode
+*        The element associated with the widget.
+*/
+const FastListWidget = module.exports = function FastListWidget(aNode) {
+this.document = aNode.ownerDocument;
+this.window = this.document.defaultView;
+this._parent = aNode;
+this._fragment = this.document.createDocumentFragment();
+// This is a prototype element that each item added to the list clones.
+this._templateElement = this.document.createElement("hbox");
+// Create an internal scrollbox container.
+this._list = this.document.createElement("scrollbox");
+this._list.className = "fast-list-widget-container theme-body";
+this._list.setAttribute("flex", "1");
+this._list.setAttribute("orient", "vertical");
+this._list.setAttribute("tabindex", "0");
+this._list.addEventListener("keypress", e => this.emit("keyPress", e), false);
+this._list.addEventListener("mousedown", e => this.emit("mousePress", e), false);
+this._parent.appendChild(this._list);
+this._orderedMenuElementsArray = [];
+this._itemsByElement = new Map();
+// This widget emits events that can be handled in a MenuContainer.
+EventEmitter.decorate(this);
+// Delegate some of the associated node's methods to satisfy the interface
+// required by MenuContainer instances.
+ViewHelpers.delegateWidgetAttributeMethods(this, aNode);
+ViewHelpers.delegateWidgetEventMethods(this, aNode);
+}
+FastListWidget.prototype = {
+/**
+* Inserts an item in this container at the specified index, optionally
+* grouping by name.
+*
+* @param number aIndex
+*        The position in the container intended for this item.
+* @param nsIDOMNode aContents
+*        The node to be displayed in the container.
+* @param Object aAttachment [optional]
+*        Extra data for the user.
+* @return nsIDOMNode
+*         The element associated with the displayed item.
+*/
+insertItemAt: function(aIndex, aContents, aAttachment={}) {
+let element = this._templateElement.cloneNode();
+element.appendChild(aContents);
+if (aIndex >= 0) {
+throw new Error("FastListWidget only supports appending items.");
+}
+this._fragment.appendChild(element);
+this._orderedMenuElementsArray.push(element);
+this._itemsByElement.set(element, this);
+return element;
+},
+/**
+* This is a non-standard widget implementation method. When appending items,
+* they are queued in a document fragment. This method appends the document
+* fragment to the dom.
+*/
+flush: function() {
+this._list.appendChild(this._fragment);
+},
+/**
+* Removes all of the child nodes from this container.
+*/
+removeAllItems: function() {
+let parent = this._parent;
+let list = this._list;
+while (list.hasChildNodes()) {
+list.firstChild.remove();
+}
+this._selectedItem = null;
+this._orderedMenuElementsArray.length = 0;
+this._itemsByElement.clear();
+},
+/**
+* Remove the given item.
+*/
+removeChild: function(child) {
+throw new Error("Not yet implemented");
+},
+/**
+* Gets the currently selected child node in this container.
+* @return nsIDOMNode
+*/
+get selectedItem() {
+return this._selectedItem;
+},
+/**
+* Sets the currently selected child node in this container.
+* @param nsIDOMNode child
+*/
+set selectedItem(child) {
+let menuArray = this._orderedMenuElementsArray;
+if (!child) {
+this._selectedItem = null;
+}
+for (let node of menuArray) {
+if (node == child) {
+node.classList.add("selected");
+this._selectedItem = node;
+} else {
+node.classList.remove("selected");
+}
+}
+this.ensureElementIsVisible(this.selectedItem);
+},
+/**
+* Returns the child node in this container situated at the specified index.
+*
+* @param number index
+*        The position in the container intended for this item.
+* @return nsIDOMNode
+*         The element associated with the displayed item.
+*/
+getItemAtIndex: function(index) {
+return this._orderedMenuElementsArray[index];
+},
+/**
+* Adds a new attribute or changes an existing attribute on this container.
+*
+* @param string name
+*        The name of the attribute.
+* @param string value
+*        The desired attribute value.
+*/
+setAttribute: function(name, value) {
+this._parent.setAttribute(name, value);
+if (name == "emptyText") {
+this._textWhenEmpty = value;
+}
+},
+/**
+* Removes an attribute on this container.
+*
+* @param string name
+*        The name of the attribute.
+*/
+removeAttribute: function(name) {
+this._parent.removeAttribute(name);
+if (name == "emptyText") {
+this._removeEmptyText();
+}
+},
+/**
+* Ensures the specified element is visible.
+*
+* @param nsIDOMNode element
+*        The element to make visible.
+*/
+ensureElementIsVisible: function(element) {
+if (!element) {
+return;
+}
+// Ensure the element is visible but not scrolled horizontally.
+let boxObject = this._list.boxObject.QueryInterface(Ci.nsIScrollBoxObject);
+boxObject.ensureElementIsVisible(element);
+boxObject.scrollBy(-this._list.clientWidth, 0);
+},
+/**
+* Sets the text displayed in this container when empty.
+* @param string aValue
+*/
+set _textWhenEmpty(aValue) {
+if (this._emptyTextNode) {
+this._emptyTextNode.setAttribute("value", aValue);
+}
+this._emptyTextValue = aValue;
+this._showEmptyText();
+},
+/**
+* Creates and appends a label signaling that this container is empty.
+*/
+_showEmptyText: function() {
+if (this._emptyTextNode || !this._emptyTextValue) {
+return;
+}
+let label = this.document.createElement("label");
+label.className = "plain fast-list-widget-empty-text";
+label.setAttribute("value", this._emptyTextValue);
+this._parent.insertBefore(label, this._list);
+this._emptyTextNode = label;
+},
+/**
+* Removes the label signaling that this container is empty.
+*/
+_removeEmptyText: function() {
+if (!this._emptyTextNode) {
+return;
+}
+this._parent.removeChild(this._emptyTextNode);
+this._emptyTextNode = null;
+},
+window: null,
+document: null,
+_parent: null,
+_list: null,
+_selectedItem: null,
+_orderedMenuElementsArray: null,
+_itemsByElement: null,
+_emptyTextNode: null,
+_emptyTextValue: ""
+};