plasma-framework/declarativeimports/plasmacomponents/qml/PageStack.js
2011-11-01 22:45:38 +01:00

236 lines
7.7 KiB
JavaScript

/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the Qt Components project.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
** the names of its contributors may be used to endorse or promote
** products derived from this software without specific prior written
** permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
** $QT_END_LICENSE$
**
****************************************************************************/
// Page stack. Items are page containers.
var pageStack = [];
// Page component cache map. Key is page url, value is page component.
var componentCache = {};
// Returns the page stack depth.
function getDepth() {
return pageStack.length;
}
// Pushes a page on the stack.
function push(page, properties, replace, immediate) {
// page order sanity check
if ((!replace && page == currentPage)
|| (replace && pageStack.length > 1
&& page == pageStack[pageStack.length - 2].page)) {
throw new Error("Cannot navigate so that the resulting page stack has two consecutive entries of the same page instance.");
}
// figure out if more than one page is being pushed
var pages;
if (page instanceof Array) {
pages = page;
page = pages.pop();
if (page.createObject === undefined && page.parent === undefined && typeof page != "string") {
properties = properties || page.properties;
page = page.page;
}
}
// get the current container
var oldContainer = pageStack[pageStack.length - 1];
// pop the old container off the stack if this is a replace
if (oldContainer && replace) {
pageStack.pop();
}
// push any extra defined pages onto the stack
if (pages) {
var i;
for (i = 0; i < pages.length; i++) {
var tPage = pages[i];
var tProps;
if (tPage.createObject === undefined && tPage.parent === undefined && typeof tPage != "string") {
tProps = tPage.properties;
tPage = tPage.page;
}
pageStack.push(initPage(tPage, tProps));
}
}
// initialize the page
var container = initPage(page, properties);
// push the page container onto the stack
pageStack.push(container);
depth = pageStack.length;
currentPage = container.page;
// perform page transition
immediate = immediate || !oldContainer;
var orientationChange = false;
if (oldContainer) {
orientationChange = orientationChanges(oldContainer.page, container.page);
oldContainer.pushExit(replace, immediate, orientationChange);
}
// sync tool bar
var tools = container.page.tools || null;
if (toolBar) {
toolBar.setTools(tools, immediate ? "set" : replace ? "replace" : "push");
}
container.pushEnter(immediate, orientationChange);
return container.page;
}
// Initializes a page and its container.
function initPage(page, properties) {
var container = containerComponent.createObject(root);
var pageComp;
if (page.createObject) {
// page defined as component
pageComp = page;
} else if (typeof page == "string") {
// page defined as string (a url)
pageComp = componentCache[page];
if (!pageComp) {
pageComp = componentCache[page] = Qt.createComponent(page);
}
}
if (pageComp) {
if (pageComp.status == Component.Error) {
throw new Error("Error while loading page: " + pageComp.errorString());
} else {
// instantiate page from component
page = pageComp.createObject(container, properties || {});
}
} else {
// copy properties to the page
for (var prop in properties) {
if (properties.hasOwnProperty(prop)) {
page[prop] = properties[prop];
}
}
}
container.page = page;
if (page.parent == null) {
container.owner = container;
} else {
container.owner = page.parent;
}
// the page has to be reparented if
if (page.parent != container) {
page.parent = container;
}
if (page.pageStack !== undefined) {
page.pageStack = root;
}
page.anchors.fill = container
return container;
}
// Pops a page off the stack.
function pop(page, immediate) {
// make sure there are enough pages in the stack to pop
if (pageStack.length > 1) {
// pop the current container off the stack and get the next container
var oldContainer = pageStack.pop();
var container = pageStack[pageStack.length - 1];
if (page !== undefined) {
// an unwind target has been specified - pop until we find it
while (page != container.page && pageStack.length > 1) {
container.cleanup();
pageStack.pop();
container = pageStack[pageStack.length - 1];
}
}
depth = pageStack.length;
currentPage = container.page;
// perform page transition
var orientationChange = orientationChanges(oldContainer.page, container.page);
oldContainer.popExit(immediate, orientationChange);
container.popEnter(immediate, orientationChange);
// sync tool bar
var tools = container.page.tools || null;
if (toolBar) {
toolBar.setTools(tools, immediate ? "set" : "pop");
}
return oldContainer.page;
} else {
return null;
}
}
// Checks if the orientation changes between oldPage and newPage
function orientationChanges(oldPage, newPage) {
return newPage.orientationLock != PageOrientation.Automatic
&& newPage.orientationLock != PageOrientation.LockPrevious
&& newPage.orientationLock != oldPage.orientationLock
}
// Clears the page stack.
function clear() {
var container;
while (container = pageStack.pop()) {
container.cleanup();
}
depth = 0;
currentPage = null;
}
// Iterates through all pages in the stack (top to bottom) to find a page.
function find(func) {
for (var i = pageStack.length - 1; i >= 0; i--) {
var page = pageStack[i].page;
if (func(page)) {
return page;
}
}
return null;
}