iOS7 QLPreviewController 更改导航栏颜色？

Question

我如何在 QLPreviewController 中设置半透明属性我已经尝试了下面的代码但它不起作用

  QLPreviewController *previewer = [[QLPreviewController alloc] init];
// Set data source
[previewer setDataSource:self];
[previewer setDelegate:self];
previewer.edgesForExtendedLayout = UIRectEdgeNone;
[previewer setCurrentPreviewItemIndex:index];
[self.navigationController.navigationBar setTranslucent:NO];
[self.navigationController setToolbarHidden:NO];
[[self navigationController] pushViewController:previewer animated:YES];

谢谢

Answer 1

你可以使用这个:

UINavigationBar *navBar =  [UINavigationBar appearanceWhenContainedIn:[QLPreviewController class], nil];
[navBar setBackgroundImage:[UIImage imageNamed:@"navigation-bg-ios7.png"] forBarMetrics:UIBarMetricsDefault];

我试过了，效果很好。