javascript to check css element

[benanderson_475]

I have some simple JavaScript to hide/show images based on group address, 
how can i check css element before making next change like the below.
Many Thanks

Code:

$(function(){
  grp.listen('1/1/1', function(object, state) {
     if (state == 'value' && object.value == true) {
     //Check if css element .hidebyknx is shown then continue    
     $(".hidebyknx").addClass("hide");
     } else if (state == 'value' && object.value == false) {
         $(".hidebyknx").removeClass("hide");
     }
  }, true);
});

[Erwin van der Zwart]

Why is that important? If it's already hidden it has no infuence at all to remove the class again in the DOM ..

You could check with hasClass() method

[admin]

The whole script can be written much shorter, but for this to work the object value must be binary (true/false).

Code:

$(function(){
   grp.listen('1/1/1', function(object, state) {
      $(".hidebyknx").toggleClass("hide", object.value);
   }, true);
});

[benanderson_475]

Why is that important? If it's already hidden it has no infuence at all to remove the class again in the DOM ..

You could check with hasClass() method

I have another object i am listening to (same code as above different obj) also show/hide the same vis element and I want to check if it’s hidden or not before changing etc, I will have a look at the hasClass() function thanks

[admin]

If you want to do a kind of AND/OR gate then you need this. Change group addresses as needed and you can change && (AND) to || (OR).

Code:

$(function(){
   var v1 = false, v2 = false;

   function set() {
      $(".hidebyknx").toggleClass("hide", v1 && v2);
   }

   grp.listen('1/1/1', function(object, state) {
      v1 = object.value;
      set();
   }, true);

   grp.listen('1/1/2', function(object, state) {
      v2 = object.value;
      set();
   }, true);
});

[benanderson_475]

If you want to do a kind of AND/OR gate then you need this. Change group addresses as needed and you can change && (AND) to || (OR).

Code:

$(function(){
   var v1 = false, v2 = false;

   function set() {
      $(".hidebyknx").toggleClass("hide", v1 && v2);
   }

   grp.listen('1/1/1', function(object, state) {
      v1 = object.value;
      set();
   }, true);

   grp.listen('1/1/2', function(object, state) {
      v2 = object.value;
      set();
   }, true);
});

Yes this is what i am after, works well many thanks, 

Also how can i request the value for both obj on page load? something like the below? grp.write() works for me but not grp.read() also is there a list of functions that are available in the custom js to interact with objects from the vis etc.

Code:

  $(document).ready(function() {
    grp.read('1/1/1')
    grp.read('1/1/2')
   
 });

[admin]

Do you really need to call read here? grp.listen executes the callback function with the current object value once the callback is registered.

[benanderson_475]

Do you really need to call read here? grp.listen executes the callback function with the current object value once the callback is registered.

Not really, although if I reload the page from browser I need to wait until the next callback event until the vis element is hidden again etc