// --------------------------------------------------------------------------- // asynch.js: provides javascript functions for asynch fetching // --------------------------------------------------------------------------- // Part of the Juniper website rendering framework, // http://immortalcookie.com/juniper // Copyright (C) 2006 Eric Miller // eric@immortalcookie.com // // --------------------------------------------------------------------------- // This library is free software; you can redistribute it and/or // modify it under the terms of the GNU Lesser General Public // License as published by the Free Software Foundation; either // version 2.1 of the License, or (at your option) any later version. // // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU // Lesser General Public License for more details. // // You should have received a copy of the GNU Lesser General Public // License along with this library; if not, write to the Free Software // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA // // Lesser GPL license text: // http://www.gnu.org/licenses/lgpl.txt // // The Creative Commons GNU-LGPL Summary: // http://creativecommons.org/licenses/LGPL/2.1/ // --------------------------------------------------------------------------- // asynch.js // depends on // prototype package // asynch.php // js_base.js // // Glue between prototype's AJAX functions and Juniper's rendering engine. // Allows asynch rendering on a per-element basis. juniper.asynch = new Object(); with( juniper ){ // maps elements waiting for asynch response -> indicator elements asynch.indicatorMap = new juniper.Map(); // maps indicator elements -> request stacks asynch.requestMap = new juniper.Map(); /* juniper.asynch.swapContentIn Swap the content of a DOM element with the content of a Juniper element as fetched and rendered in the current page's lineage and context. iDOMElement: id of a DOM object, the object itself or a prototype success/failure object. See prototype docs for more info. iReplacementName: the name of a juniper element visible from the current page's lineage and context. iArgs: (optional) a string of juniper-formatted attribute-value arguments for element iReplacementName, eg: "time='morning' day='Tuesday' activity='whittling'" iIndicatorDOMElement: (optional, id | "auto" ) the string id of a dom element in which you wish a "working" indicator to appear, or "auto" if you would like an indicator prepended to iDOMElement. Consecutive requests specifying the same id are supported; the indicator won't go away until the last request has finished. iLineage: override the current lineage base by passing a full fs path. iInsertion: a prototype insertion object. */ asynch.swapContentIn = function( iDOMElementID, iReplacementName, iArgs, iIndicatorDOMElementID, iLineageBase, iInsertion ) { if( iLineageBase == undefined ) iLineageBase = juniper.asynch.altLineageBase; var params = "juniper-asynch-request=yes&juniper-replace-element=yes&alt-lineage-base=" + iLineageBase + "&juniper-element=" + iReplacementName + "&attributes=" + encodeURIComponent( iArgs ); var domElement = $( iDOMElementID ); var completionFunc; if( iIndicatorDOMElementID != undefined && iIndicatorDOMElementID != "" ) completionFunc = function(){ asynch.hideIndicatorForDOMObject( domElement ) }; else completionFunc = function(){}; var updater = new Ajax.Updater( domElement, asynch.endpointURL, { method: 'get', parameters: params, insertion: iInsertion, onFailure: asynch.updateFailureHandler, onException: asynch.updateExceptionHandler, onSuccess: asynch.updateSuccessHandler, onComplete: completionFunc, evalScripts: true } ); asynch.showIndicatorFor( domElement, iIndicatorDOMElementID ); } asynch.showIndicatorFor = function( iDOMElement, iIndicatorDOMElementID ) { if( iIndicatorDOMElementID == "auto" ) { // user didn't supply an element for us. we make one up and insert it // before the element that will be modified by the asynch fetch var indicator = document.createElement( 'img' ); indicator.style.textAlign = "center"; indicator.style.verticalAlign = "middle"; indicator.setAttribute( "src", asynch.indicatorURL ); indicator.setAttribute( "remove", true ); iDOMElement.parentNode.insertBefore( indicator, iDOMElement ); asynch.requestMap.add( indicator, { requests: 1 } ); asynch.indicatorMap.add( iDOMElement, indicator ); } else if( iIndicatorDOMElementID != undefined && iIndicatorDOMElementID != "" ) { // user supplied an element for us. var indicator = asynch.indicatorMap.valueForKey( iDOMElement ); if( indicator == null ) { // but the indicator img is not already present var indicatorContainer = $( iIndicatorDOMElementID ); var imgs = indicatorContainer.getElementsByTagName( "img" ); var indicator = null; if( imgs.length > 0 ) indicator = asynch.indicatorMap.add( iDOMElement, imgs[ 0 ] ); // this indicator may already exist and be running if( asynch.requestMap.valueForKey( indicator ) == null ) { // it is not already mapped in. indicator = document.createElement( 'img' ); indicator.setAttribute( "src", asynch.indicatorURL ); indicatorContainer.appendChild( indicator ); asynch.indicatorMap.add( iDOMElement, indicator ); asynch.requestMap.add( indicator, { requests: 1 } ); } else { // the indicator element should already have its img. // we just bump its request stack. asynch.requestMap.valueForKey( indicator ).requests++; } } else { asynch.requestMap.valueForKey( indicator ).requests++; } } } asynch.hideIndicatorForDOMObject = function( iDOMObject ) { var stackObj; var indicator = asynch.indicatorMap.valueForKey( iDOMObject ); if( indicator ) stackObj = asynch.requestMap.valueForKey( indicator ); if( stackObj ) stackObj.requests--; else throw { message:"map is not in an expected state." }; if( stackObj.requests == 0 ) { // it may no longer be in the document. if( typeof( indicator.parentNode ) != undefined && indicator.parentNode != null ) Element.remove( indicator ); asynch.requestMap.erase( indicator ); asynch.indicatorMap.erase( iDOMObject ); } else { // while the indicator stack is not empty, nonetheless this waiting // element has completed so we should remove it from the map. asynch.indicatorMap.erase( iDOMObject ); } } asynch.updateSuccessHandler = function( iRequest, iResponse ) { } asynch.updateFailureHandler = function( iRequest, iResponse ) { alert( "Asynch fetch server error: " + iResponse ) } asynch.updateExceptionHandler = function( iRequest, iException ) { alert( "Asynch fetch failed with exception: " + iException.message ) } /* juniper_insertBefore Like above, but inserts before the passed DOM element. */ asynch.insertBefore = function( iDOMElementID, iInsertionName, iArgs, iIndicatorDOMElementID, iLineageBase ) { asynch.swapContentIn( iDOMElementID, iInsertionName, iArgs, iIndicatorDOMElementID, iLineageBase, Insertion.Before ); } /* juniper_insertAfter Like above, but inserts after the passed DOM element. */ asynch.insertAfter = function( iDOMElementID, iInsertionName, iArgs, iIndicatorDOMElementID, iLineageBase ) { asynch.swapContentIn( iDOMElementID, iInsertionName, iArgs, iIndicatorDOMElementID, iLineageBase, Insertion.After ); } /* juniper_insertTop Like above, but inserts as first child of the passed DOM element. */ asynch.insertTop = function( iDOMElementID, iInsertionName, iArgs, iIndicatorDOMElementID, iLineageBase ) { asynch.swapContentIn( iDOMElementID, iInsertionName, iArgs, iIndicatorDOMElementID, iLineageBase, Insertion.Top ); } /* juniper_insertBottom Like above, but inserts as last child of the passed DOM element. */ asynch.insertBottom = function( iDOMElementID, iInsertionName, iArgs, iIndicatorDOMElementID, iLineageBase ) { asynch.swapContentIn( iDOMElementID, iInsertionName, iArgs, iIndicatorDOMElementID, iLineageBase, Insertion.Bottom ); } };