iOS如何呈现视图，然后使用视图中的输入重新运行调用方法

I'm working on an iOS app that uses a tab bar. An item is scanned using a barcode reader, and a callback method sets the tab bar item to the result view, then sends the request to the server. The callback from the server populates the display and the result view is shown. I'm working on an iOS app that uses a tab bar.