how to force interfaceOrientation programmatically on iPhone?
<p>how to force it show on UIDeviceOrientationPortrait only?</p>

<p>example 
layer1 display on UIInterfaceOrientationLandscapeLeft </p>

<p>when i pushViewController to layer2 it will auto show on UIInterfaceOrientationLandscapeLeft
how can i force it to display UIDeviceOrientationPortrait?</p>
