Changing images of toolbar buttons dynamicaly

I have a tool bar with buttons whose image is set to a pa开发者_StackOverflow社区rticular image.When the user clicks a button in the main view, i want to change the image of one of the toolbar buttons to another image.I tried many methods.Everything ran without errors, but none showed any change in toolbar.Any suggestions?

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There is a tutorial for this: How-to-change-a-uibarbuttonitem-in-the-iphone-toolbar

This is a great tutorial because it goes over changing the images based on state as well.