svgedit/editor/document.js

105 lines
2.6 KiB
JavaScript

/**
* Package: svgedit.document
*
* Licensed under the Apache License, Version 2
*
* Copyright(c) 2010 Jeff Schiller
*/
/*
TODOs:
Phase 1:
- migrate svgcanvas to using a Document object for its calls to getNextId() and getId()
- migrate usages of randomizeIds() to proxy into the Document
Phase 2:
- migrate uniquifyElems into this module
- migrate as many usages of svgcontent in svgcanvas to using a Document instance as possible
*/
// Dependencies:
// 1) jQuery
(function() {
if (!window.svgedit) {
window.svgedit = {};
}
if (!svgedit.document) {
svgedit.document = {};
}
var svg_ns = "http://www.w3.org/2000/svg";
var se_ns = "http://svg-edit.googlecode.com";
/**
* This class encapsulates the concept of a SVG-edit document.
*
* @param svgElem {SVGSVGElement} The SVG DOM Element that this JS object
* encapsulates. If the svgElem has a se:nonce attribute on it, then
* IDs will use the nonce as they are generated.
* @param opt_idPrefix {String} The ID prefix to use. Defaults to "svg_"
* if not specified.
*/
svgedit.document.Document = function(svgElem, opt_idPrefix) {
if (!svgElem || !svgElem.tagName || !svgElem.namespaceURI ||
svgElem.tagName != 'svg' || svgElem.namespaceURI != svg_ns) {
throw "Error: svgedit.document.Document instance initialized without a <svg> element";
}
this.svgElem_ = svgElem;
this.obj_num = 0;
this.idPrefix = opt_idPrefix || "svg_";
// Determine if the <svg> element has a nonce on it
this.nonce_ = this.svgElem_.getAttributeNS(se_ns, 'nonce') || "";
};
svgedit.document.Document.prototype.getElem_ = function(id) {
if(this.svgElem_.querySelector) {
// querySelector lookup
return this.svgElem_.querySelector('#'+id);
} else {
// jQuery lookup: twice as slow as xpath in FF
return $(this.svgElem_).find('[id=' + id + ']')[0];
}
};
svgedit.document.Document.prototype.getSvgElem = function() {
return this.svgElem_;
}
svgedit.document.Document.prototype.getNonce = function() {
return this.nonce_;
};
/**
* Returns the latest object id as a string.
* @return {String} The latest object Id.
*/
svgedit.document.Document.prototype.getId = function() {
return this.nonce_ ?
this.idPrefix + this.nonce_ +'_' + this.obj_num :
this.idPrefix + this.obj_num;
};
/**
* Returns the next object Id as a string.
* @return {String} The next object Id to use.
*/
svgedit.document.Document.prototype.getNextId = function() {
// always increment the obj_num every time we call getNextId()
this.obj_num++;
// ensure the ID does not exist
var id = this.getId();
while (this.getElem_(id)) {
this.obj_num++;
id = this.getId();
}
return id;
};
})();