/** * functionsJS * Useful client side javaScript functions * @author Mark Brook * 03-Jan-2008 */ var elementArray = new Array('P','H1', 'H2', 'H3','H4', 'H5', 'H6','LI', 'UL', 'A','INPUT','LABEL','TEXTAREA', 'IMG', 'TD', 'SPAN' ); //array of elements to colour on mouse events var fntAdjustmentInPx; //current font adjustment var b; //reference to the body element //zoomtimer vars var zoomSecs; var zoomTimerID = null; var zoomTimerRunning = false; var zoomDelay = 500; /*=================== Zoom functions =================*/ /* * this function starts the zooming process * @param string direction - in or out */ function startZoom(direction){ zoomSecs = 1 StopTheZoomClock() StartTheZoomTimer(direction); }// end startZoom function stopZoom(){ StopTheZoomClock(); } function StartTheZoomTimer(direction){ //every half a second, zoom in the required direction if (zoomSecs == 0){ if (direction == 1){ zoomIn(); }else{ zoomOut(); }//end if }else{ zoomSecs -= 1; }//end if zoomTimerRunning = true zoomTimerID = self.setTimeout("StartTheZoomTimer(" + direction + ")", zoomDelay) }//end startTheZoomTimer function StopTheZoomClock() { if(zoomTimerRunning) clearTimeout(zoomTimerID) zoomTimerRunning = false } /* * zoomIn is used to increase the size of all text in the body * of an html page. */ function zoomIn(){ var fs; //retrieved font size //+ 1px to the size fntAdjustmentInPx += 1; for (i = 0; i <= elementArray.length; i++){ e = document.getElementsByTagName(elementArray[i]) for (j = 0; j <= e.length; j ++){ try{ //get the current font size for this element fs = retrieveComputedStyle(e[j], 'fontSize'); /* * some browser return px, some em and some% * http://sureshjain.wordpress.com/2007/07/06/53/ * tells us that 1 em = 100% = 12pt = 16px */ if (fs.indexOf('%') >= 0){ //remove the % from the fs fs = (parseInt(fs.replace("%", ""))) / 100 * 16; }else if (fs.indexOf('em') >= 0){ //remove the em from the fs fs = (parseInt(fs.replace("em", ""))) * 16; }else{ //remove the px from the fs fs = parseInt(fs.replace("px", "")); }//end if //+ 1px to the size fs += 1; //put the px back at the end e[j].style.fontSize = fs + 'px'; }catch(err){ //if an element does not exist, an error will //be thrown. Don't display it } }//end for }//end for setSessionCookie('fontAdjustmentInPx', fntAdjustmentInPx); }//end zoomIn /* * zoomIn is used to increase the size of all text in the body * of an html page. */ function zoomOut(){ var fs; //retrieved font size //- 1px to the size fntAdjustmentInPx = parseInt(fntAdjustmentInPx) - 1; for (i = 0; i <= elementArray.length; i++){ e = document.getElementsByTagName(elementArray[i]) for (j = 0; j <= e.length; j ++){ try{ //get the current font size for this element fs = retrieveComputedStyle(e[j], 'fontSize'); /* * some browser return px, some em and some% * http://sureshjain.wordpress.com/2007/07/06/53/ * tells us that 1 em = 100% = 12pt = 16px */ if (fs.indexOf('%') >= 0){ //remove the % from the fs fs = (parseInt(fs.replace("%", ""))) / 100 * 16; }else if (fs.indexOf('em') >= 0){ //remove the em from the fs fs = (parseInt(fs.replace("em", ""))) * 16; }else{ //remove the px from the fs fs = parseInt(fs.replace("px", "")); }//end if fs -= 1; //put the px back at the end e[j].style.fontSize = fs + 'px'; }catch(err){ //if an element does not exist, an error will //be thrown. Don't display it } }//end for }//end for setSessionCookie('fontAdjustmentInPx', fntAdjustmentInPx); }//end zoomOut /* * resetZoom is used to go through all page elements and adjust * them to default size i.e. 0 adjustment */ function resetZoom(){ fntAdjustmentInPx = "0"; setSessionCookie('fontAdjustmentInPx', fntAdjustmentInPx); location.reload(true); }//end resetZoom /* * setZoom is used to go through all page elements and adjust * them according to the fontAdjusmentInPx value which is stored * in the sites cookie */ function setZoom(){ //find out if a cookie exists with a font size for this page fntAdjustmentInPx = getCookie('fontAdjustmentInPx'); if (fntAdjustmentInPx == false){ //if no cookie exists, set fntAdjustmentInPx to 0 fntAdjustmentInPx = 0; }else{ fntAdjustmentInPx = parseInt(fntAdjustmentInPx); } var fs; //retrieved font size for (i = 0; i <= elementArray.length; i++){ e = document.getElementsByTagName(elementArray[i]) for (j = 0; j <= e.length; j ++){ try{ //get the current font size for this element fs = retrieveComputedStyle(e[j], 'fontSize'); //remove the px from the fs /* * some browser return px, some em and some% * http://sureshjain.wordpress.com/2007/07/06/53/ * tells us that 1 em = 100% = 12pt = 16px */ if (fs.indexOf('%') >= 0){ //remove the % from the fs fs = (parseInt(fs.replace("%", ""))) / 100 * 16; }else if (fs.indexOf('em') >= 0){ //remove the em from the fs fs = (parseInt(fs.replace("em", ""))) * 16; }else{ //remove the px from the fs fs = parseInt(fs.replace("px", "")); }//end if //adjust the size according to fontAdjustment fs += fntAdjustmentInPx; //put the px back at the end e[j].style.fontSize = fs + 'px'; //alert(e[j].nodeName + ' ' + fs + 'px'); }catch(err){ //if an element does not exist, an error will //be thrown. Don't display it } }//end for }//end for }//end set zoom /** * used to calculate the computed style of an element * taking into account the various css rules * * I took this function from (James & Adams, 2006, pp. 205-206) * * James, E. & Adams, C. (2006) JavaScript Anthology 101 Essential Tips, Tricks & Hacks. SitePoint Pty. Ltd. * * @param element - the element whos style is to be read * @param styleProerty - property to retrieve */ function retrieveComputedStyle(element, styleProperty) { var computedStyle = null; if (typeof element.currentStyle != "undefined") { computedStyle = element.currentStyle; } else { computedStyle = document.defaultView.getComputedStyle(element, null); } return computedStyle[styleProperty]; }//end retrieveComputedStyle /*=================End zoom functions =================*/ /*================= Cookie functions ===========================*/ /* * setCookie * @param string name - name of the cookie * @param string value - the value of the cookie */ function setCookie(name, value){ var cookieName =name; var cookieValue = value; var exdate=new Date(); //get the current date and add 365 days to it exdate.setDate(exdate.getDate() + 365); var theCookie = cookieName + "=" + cookieValue + ';expires=' + exdate.toGMTString(); document.cookie = theCookie; }//end setCookie /* * setSessionCookie * @param string name - name of the cookie * @param string value - the value of the cookie */ function setSessionCookie(name, value){ document.cookie=name+ "=" + value; }//end setSessionCookie /* * getCookie function will retrieve a cookie valeu * @param string searchName * * @return string - the cookie value * */ function getCookie(searchName){ var cookies = document.cookie.split(";"); for (var i = 0; i < cookies.length; i++) { var cookieCrumbs = cookies[i].split("="); var cookieName = cookieCrumbs[0]; //if there is a leading space, remove it if(cookieName.substr(0,1) == " "){ cookieName = cookieName.substr(1, cookieName.length - 1); }//end if var cookieValue = cookieCrumbs[1]; if (cookieName == searchName){ return cookieValue; }//end if }//end if return false; }//end getCookie /*========================= End cookie functions =============*/ /*================================================= Onload ===================================================*/ window.onload = function(e) { setZoom(); } window.onunload = function(e) { }