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javascriptfunctiontrigger.ioforge

Trigger.io: forge.prefs Variable Scope in a function

We are having difficulty assigning a forge.prefs value to a variable, so that we can pass it on as a parameter.

This is a sample call:

forge.prefs.get('offset_val' function(offset1){
     offset = offset1; 
})
forge.prefs.get('id', function(val){
     uid = val;
})

load_my_car(uid,offset);

It is returning undefined and it is very inconvenient to call it in a nested prefs command.

Can someone help us regarding this problem?

Solution

  • forge.prefs.get() is probably an asynchronous function call, which means that its callback is executed somewhat delayed. In your example load_my_car() is executed before the two callbacks are fired, so the variables are still undefined.

    You have to make sure that the callbacks are fired before calling load_my_car(), try this:

    forge.prefs.get('offset_val' function(offset1){
  forge.prefs.get('id', function(val){
    load_my_car(val,offset1);
  }); 
});

    If you really don't want to have two nested forge.prefs.get() you'd need to check which callback finishes first and then only call load_my_car() after the second finished.