Go to any empty space on your sheet where the object to be clicked is, right click and go to the Sheet properties, Triggers tab. Select the ID of the object you want to be clicked and add a new action OnActivate, Add Action, Layout, Activate Sheet, and specify the sheet ID. Note that every time you click out of the object and click on it again, you activate it. Once you are selecting in a chart it's still activated, but as soon as you click on any other object, blank space, chart, etc... you will be deactivating it.
Hope that helps.