Are global attributes possible in lightning component?

Question

It is possible to create attribute as global, I mean that attribute can be get & set in any lightning component or can we set the parent component attributes?

Answer 1

There are couple ways to handle this

1.Approach 1 involves using a static resource file to store all the global values

Here is how a code in your static resource look like

(function(w){
  "use strict"; //Optional because LC on LockerService active runs in strict mode

  var globalConstants = {
    "variable1":"abc",
    "variable2":"zyz"
  };

  w.globalvalues = globalConstants;

})(window);

And then in lightning component you will use like below

  ltng:require scripts="{!$Resource.TestScript}" afterScriptsLoaded="{!c.afterScriptsLoaded}" />
   <ui:button label="Do job" press="{!c.populateConstants}"/>

The controller

populateConstants : function(cmp){
  globalvalues.variable1; 
  globalvalues.variable2; 
}

Note you can use this on all init handler to load this data

2.Use an attribute in Parent component and then trickle down the attribute in all the components like below

<attribute name="constant" type="String" default="Hello"/>

The child will have similar attribute and you will call like below

<c:childcomponent constant="{!v.constant}"/>

Answer 2

I got the solution, By using lightning event we can pass values from any component to any component like from outer component to inner component, inner component to outer component and from sibling component too.

Steps:

1. Create a lightning event with attributes which you want to pass to cmp on particular event.

2. Register the lightning event in the component from where you want to pass the values/from where the event is gona happen.

3. Add handler in component in which you are going to access the parameter

Thanks!

Answer 3

See one answer to With Summer 18 and LockerService is there any global storage? The concept is to pass a global object from each outer container to each inner container. This "global" object is shared and can be modified by any component that is given the reference.