source: admin/js/confirm-close.js @ 3449:bddaf36a61e9

function confirmClose() {

     if (arguments.length > 0) {
          for (var i = 0; i < arguments.length; i++) {
               this.forms_id.push(arguments[i]);
          }
     }
};

confirmClose.prototype = {
     prompt: 'You have unsaved changes.',
     forms_id: new Array(),
     forms: new Array(),
     formSubmit: false,

     getCurrentForms: function() {
          // Store current form's element's values

          var formsInPage = this.getForms();
          var f, e;
          var This = this;
          this.forms = new Array();
          for (var i = 0; i < formsInPage.length; i++) {
               f = formsInPage[i];
               var tmpForm = new Array();
               for (var j = 0; j < f.elements.length; j++) {
                    e = this.getFormElementValue(f[j]);
                    if (e != undefined) {
                         tmpForm.push(e);
                    }
               }
               this.forms.push(tmpForm);

               chainHandler(f, 'onsubmit', function() {
                    This.formSubmit = true;
               });
          }
     },

     compareForms: function() {
          // Compare current form's element's values to their original values
          // Return false if any difference, else true

          if (this.forms.length == 0) {
               return true;
          }

          var formsInPage = this.getForms();
          var f, e;
          for (var i = 0; i < formsInPage.length; i++) {
               f = formsInPage[i];
               var tmpForm = new Array();
               for (var j = 0; j < f.elements.length; j++) {
                    e = this.getFormElementValue(f[j]);
                    if (e != undefined) {
                         tmpForm.push(e);
                    }
               }
               for (var j = 0; j < this.forms[i].length; j++) {
                    if (this.forms[i][j] != tmpForm[j]) {
                         return false;
                    }
               }
          }

          return true;
     },

     getForms: function() {
          // Get current list of forms as HTMLCollection(s)

          if (!document.getElementsByTagName || !document.getElementById) {
               return new Array();
          }

          if (this.forms_id.length > 0) {
               var res = new Array();
               var f;
               for (var i = 0; i < this.forms_id.length; i++) {
                    f = document.getElementById(this.forms_id[i]);
                    if (f != undefined) {
                         res.push(f);
                    }
               }
               return res;
          } else {
               return document.getElementsByTagName('form');
          }

          return new Array();
     },

     getFormElementValue: function(e) {
          // Return current value of an form element

          if (e == undefined) {
               // Unknown object
               return undefined;
          }
          if (e.type != undefined && e.type == 'button') {
               // Ignore button element
               return undefined;
          }
          if (e.classList.contains('meta-helper') || e.classList.contains('checkbox-helper')) {
               // Ignore some application helper element
               return undefined;
          }
          if (e.type != undefined && e.type == 'radio') {
               // Return actual radio button value if selected, else null
               return this.getFormRadioValue(e);
          } else if (e.type != undefined && e.type == 'checkbox') {
               // Return actual checkbox button value if checked, else null
               return this.getFormCheckValue(e);
          } else if (e.type != undefined && e.type == 'password') {
               // Ignore password element
               return null;
          } else if (e.value != undefined) {
               // Return element value if not undefined
               return e.value;
          } else {
               // Every other case, return null
               return null;
          }
     },

     getFormCheckValue: function(e) {
          if (e.checked) {
               return e.value;
          }
          return null;
     },

     getFormRadioValue: function(e) {
          for (var i = 0; i < e.length; i++) {
               if (e[i].checked) {
                    return e[i].value;
               } else {
                    return null;
               }
          }
          return null;
     }
};

var confirmClosePage = new confirmClose();

chainHandler(window, 'onload', function() {
     confirmClosePage.getCurrentForms();
});

chainHandler(window, 'onbeforeunload', function(event_) {
     if (event_ == undefined && window.event) {
          event_ = window.event;
     }

     if (!confirmClosePage.formSubmit && !confirmClosePage.compareForms()) {
          event_.returnValue = confirmClosePage.prompt;
          return confirmClosePage.prompt;
     }
     return false;
});