pdf.js/web/pdf_outline_viewer.js
Jonas Jenwald 03f10739d8 Extract common functionality into a new BaseTreeViewer._finishRendering method
Note how the end of the `{PDFOutlineViewer, PDFAttachmentViewer, PDFLayerViewer}.render` methods share *almost* identical code, hence we can reduce some duplication by introducing the new `BaseTreeViewer` helper method here.

Furthermore, setting `this._lastToggleIsShow` can be made ever so slightly more efficient, since we don't care about the number of ".treeItemsHidden"-classes but only want to know if at least one exists.
2020-12-30 13:48:58 +01:00

180 lines
4.4 KiB
JavaScript

/* Copyright 2012 Mozilla Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import { addLinkAttributes, LinkTarget } from "pdfjs-lib";
import { BaseTreeViewer } from "./base_tree_viewer.js";
/**
* @typedef {Object} PDFOutlineViewerOptions
* @property {HTMLDivElement} container - The viewer element.
* @property {IPDFLinkService} linkService - The navigation/linking service.
* @property {EventBus} eventBus - The application event bus.
*/
/**
* @typedef {Object} PDFOutlineViewerRenderParameters
* @property {Array|null} outline - An array of outline objects.
*/
class PDFOutlineViewer extends BaseTreeViewer {
/**
* @param {PDFOutlineViewerOptions} options
*/
constructor(options) {
super(options);
this.linkService = options.linkService;
this.eventBus._on("toggleoutlinetree", this._toggleAllTreeItems.bind(this));
}
reset() {
super.reset();
this._outline = null;
}
/**
* @private
*/
_dispatchEvent(outlineCount) {
this.eventBus.dispatch("outlineloaded", {
source: this,
outlineCount,
});
}
/**
* @private
*/
_bindLink(element, { url, newWindow, dest }) {
const { linkService } = this;
if (url) {
addLinkAttributes(element, {
url,
target: newWindow ? LinkTarget.BLANK : linkService.externalLinkTarget,
rel: linkService.externalLinkRel,
enabled: linkService.externalLinkEnabled,
});
return;
}
element.href = linkService.getDestinationHash(dest);
element.onclick = () => {
if (dest) {
linkService.goToDestination(dest);
}
return false;
};
}
/**
* @private
*/
_setStyles(element, { bold, italic }) {
if (bold) {
element.style.fontWeight = "bold";
}
if (italic) {
element.style.fontStyle = "italic";
}
}
/**
* @private
*/
_addToggleButton(div, { count, items }) {
let hidden = false;
if (count < 0) {
let totalCount = items.length;
if (totalCount > 0) {
const queue = [...items];
while (queue.length > 0) {
const { count: nestedCount, items: nestedItems } = queue.shift();
if (nestedCount > 0 && nestedItems.length > 0) {
totalCount += nestedItems.length;
queue.push(...nestedItems);
}
}
}
if (Math.abs(count) === totalCount) {
hidden = true;
}
}
super._addToggleButton(div, hidden);
}
/**
* @private
*/
_toggleAllTreeItems() {
if (!this._outline) {
return;
}
super._toggleAllTreeItems();
}
/**
* @param {PDFOutlineViewerRenderParameters} params
*/
render({ outline }) {
if (this._outline) {
this.reset();
}
this._outline = outline || null;
if (!outline) {
this._dispatchEvent(/* outlineCount = */ 0);
return;
}
const fragment = document.createDocumentFragment();
const queue = [{ parent: fragment, items: outline }];
let outlineCount = 0,
hasAnyNesting = false;
while (queue.length > 0) {
const levelData = queue.shift();
for (const item of levelData.items) {
const div = document.createElement("div");
div.className = "treeItem";
const element = document.createElement("a");
this._bindLink(element, item);
this._setStyles(element, item);
element.textContent = this._normalizeTextContent(item.title);
div.appendChild(element);
if (item.items.length > 0) {
hasAnyNesting = true;
this._addToggleButton(div, item);
const itemsDiv = document.createElement("div");
itemsDiv.className = "treeItems";
div.appendChild(itemsDiv);
queue.push({ parent: itemsDiv, items: item.items });
}
levelData.parent.appendChild(div);
outlineCount++;
}
}
this._finishRendering(fragment, outlineCount, hasAnyNesting);
}
}
export { PDFOutlineViewer };