Adding an Object to Your Interface
Add a standard object to your interface by dragging it from the object library to Interface Builder.
With a storyboard or xib file open in Interface Builder, open the utility area for the workspace window by clicking in the view selector in the toolbar.
Select the object library from the library pane by clicking in the library selector bar.
Locate the object you want to add.
Scroll through the list of objects. Type into the text field in the filter bar at the bottom of the list to restrict the items displayed in the list.
Drag an object (like Button in the screenshot) from the library to either the outline view in the dock or onto the canvas.
You can design much of your user interface with standard elements such as windows, text fields, and buttons from the object library. The objects in the library meet Apple’s human interface guidelines and have been tested to ensure that they function properly.
After you drag the object from the library to Interface Builder use the built-in guides to position the object and resize it if necessary.