How to add a drop down list of buttons in uinavigation bar in objective c iPhone

I am very new to objective c and iPhone applications. I am creating a project in xcode to make an application for iPhone. I need to add a drop down list in the navigation bar of that application. I have added other buttons 开发者_运维问答to it like back button, refresh button. But Now I require a drop down list of buttons/links to it. plz tell me how can I do this.

Thanks in advance

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you can try this. I'm expanding sabby's solution. just when you add the view with button like a vertical list of buttons. use this code

CGRect customViewFrame = yourCustomView.frame;
customViewFrame.size.height = 0;
yourCustomView.frame = customViewFrame;
[UIView beginAnimations:nil context:nil];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
customViewFrame.size.height = your_desired_height;
yourCustomView.frame = customViewFrame;
[UIView commitAnimations];

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Well i think you can use customization,take a view and put the buttons on that view,as many as you want.Then you need to call that view on the click of the button on your navigation bar. This will resolve your problem.