通过appearance设置app主题

    //再plist文件中设置View controller-based status bar appearance 为 NO才能起效    [[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleLightContent];    //导航条上标题的颜色    NSDictionary *navbarTitleTextAttributes = @{NSForegroundColorAttributeName:[UIColor whiteColor]};    [[UINavigationBar appearance] setTitleTextAttributes:navbarTitleTextAttributes];    //导航条上UIBarButtonItem颜色    [[UINavigationBar appearance] setTintColor:[UIColor whiteColor]];    //TabBar选中图标的颜色,默认是蓝色    [[UITabBar appearance] setTintColor:[UIColor colorWithHex:0x15A230]];    //TabBarItem选中的颜色    [[UITabBarItem appearance] setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor colorWithHex:0x15A230]} forState:UIControlStateSelected];    //导航条的背景颜色    [[UINavigationBar appearance] setBarTintColor:[UIColor navigationbarColor]];    //TabBar的背景颜色    [[UITabBar appearance] setBarTintColor:[UIColor titleBarColor]];    [UISearchBar appearance].tintColor = [UIColor redColor];    //当某个class被包含在另外一个class内时，才修改外观。    [[UITextField appearanceWhenContainedIn:[UISearchBar class], nil] setCornerRadius:14.0];    [[UITextField appearanceWhenContainedIn:[UISearchBar class], nil] setAlpha:0.6];    UIPageControl *pageControl = [UIPageControl appearance];    pageControl.pageIndicatorTintColor = [UIColor colorWithHex:0xDCDCDC];    pageControl.currentPageIndicatorTintColor = [UIColor grayColor];    [[UITextField appearance] setTintColor:[UIColor nameColor]];    [[UITextView appearance]  setTintColor:[UIColor nameColor]];