TypeError: Object Is Not A Function (JavaScript Chrome Storage Sync)

Question

This is for accessing preferences saved in chrome.storage.sync using JavaScript for a Chrome Extension.

Code:

chrome.storage.sync.get('allWeights', function(obj) {  
          allWeights = obj.allWeights();

          chrome.storage.sync.get('allIDs', function(obj2) { 
            allIDs = obj2.allIDs();
            alert("ALL WEIGHTS: " + allWeights);
            alert("ALL IDS: " + allIDs);
         });
    });

Error:

Error in response to storage.get: TypeError: object is not a function at HTMLDocument.restore_options

And the error is pointing to the first line (chrome.storage.sync.get('allWeights').

What is causing this error and how can I fix it?

Answer 1

EDIT: This works

 chrome.storage.sync.get(null, function(items) {
        allWeights = items.allWeights;
        allIDs = items.allIDs;
        alert("ALL WEIGHTS: " + allWeights);
        alert("ALL IDS: " + allIDs);
    }); 

I had to change items.allWeights() to items.allWeights.

Apparently you can't access an object property with ()