Any ideas to add functionality when users click on a feature, they are redirected to a url that is defined in one of the fields of the feature attributes.
Yep that is the way to go.
You can add a link to the popup in the WebMap in AGOL. Other than that you would have to create a custom widget that adds a click event to the FeatureLayer and defines the field to use for the url.
Thanks. I was looking for a url redirect when you click on a feature, not a popup. Very similar of what you created on the flex. So, for js, an off-panel widget which starts up and listens when the app initiates is the way to go.
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