Gen 8.6 Web Generation calendar control fails in Web View
search cancel

Gen 8.6 Web Generation calendar control fails in Web View


Article ID: 100987


Updated On:


Gen Gen - Workstation Toolset


In Gen 8,6 an HTML Control containing JavaScript to display a Date field as a Calendar control loads successfully in a Web Generation application but fails to load in a Web View application and reports a 'null' related JavaScript error.
For example the Procedure Step/Window TEST_SCREEN has a Date field with name GEN_DATE and the HTML Control HTMLControl1 contains : 
window.onload = function(){ 
document.getElementById('GEN_DATE').type = 'DATE'; 


The browser Developer Console shows a JavaScript error e.g.
1. Chrome:
Uncaught TypeError: Cannot set property 'type' of null 
at window.onload (TEST_SCREEN_HTMLControlFrame_HTMLControl1.html:3)

2. Firefox:
TypeError: document.getElementById(...) is null 


Release: 8.x
Gen Web View 


For Web View each HTML Control and HTML Text element is rendered in a separate <iframe> tag in the HTML document and the objects outside of this iframe have to be accessed differently. Hence the 'null' related JavaScript error received at runtime. 
See Gen 8.6 documentation page Use Existing Models in Web View section "HTML Control and HTML Text".

Also the Web View controls do not use the same ID naming conventions as Web Generation and hence need to change 'document.getElementById' to 'parent.document.getElementsByClassName'.


Gen Engineering suggested using this JavaScript for the Web View Calendar control which then loads successfully: 
window.onload = function(){ 
var elements = parent.document.getElementsByClassName('GEN_DATE'); 
for(var i = 0, length = elements.length; i < length; i++) { 

elements[i].type = 'DATE';