iOS8/iphone
When setting
navigationbar.translucent = yes;
If also set
blueVC.hidesBottomBarWhenPushed = yes;
push ViewController, navigationbar right corner displays a black.
Test Results:
Black areas are UIWindow by default. I changed the UIWindow background color to white and that fixed the issue. But this just looks better, does not completely resolved.

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iOS7 strange animation when using hidesBottomBarWhenPushed
self.tabBarController.tabBar.hidden=YES;
This approach will lead to push the process tabbar disappear. It does not solve the problem.