UITabBarItem 更改图像的高度和宽度／UINavigationBar 更改样式

从苹果文档的最大大小的一张图片在 TabBar 是 30 x 30 (60 x 60 的视网膜显示器）。

我不认为它是可能采取整个 TabBar 不拉伸图像的高度。我认为最好的解决办法是中心中使用 imageInset TabBar 的图像

tabBarItem1.imageInsets = UIEdgeInsetsMake(6, 0, -6, 0);

否则你可以玩这 imageInset 和拉伸图像像在截图中

tabBarItem1.imageInsets = UIEdgeInsetsMake(0, -10, -6, -10);

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions  {


 UITabBarController *tabBarController = (UITabBarController *)self.window.rootViewController;

 UITabBar *tabBar = tabBarController.tabBar;
 UITabBarItem *tabBarItem1 = [tabBar.items objectAtIndex:0];
 UITabBarItem *tabBarItem2 = [tabBar.items objectAtIndex:1];
 UITabBarItem *tabBarItem3 = [tabBar.items objectAtIndex:2];

 //add image to tabbarItems

 tabBarItem1.imageInsets = UIEdgeInsetsMake(0, -10, -6, -10);
}

 [[UINavigationBar appearance] setTintColor:[UIColor whiteColor]];

    NSShadow *shadow = [[NSShadow alloc] init];

    shadow.shadowColor = [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.0];

    shadow.shadowOffset = CGSizeMake(0, 1);

    // [UIColor colorWithRed:245.0/255.0 green:245.0/255.0 blue:245.0/255.0 alpha:1.0]

    [[UINavigationBar appearance] setTitleTextAttributes: [NSDictionary dictionaryWithObjectsAndKeys:

                                                           [UIColor grayColor], NSForegroundColorAttributeName,

                                                           shadow, NSShadowAttributeName,

                                                           [UIFont fontWithName:@"Avenir-Medium"  size:20.0], NSFontAttributeName, nil]];

 UIBarButtonItem *cameraItem = [[UIBarButtonItem alloc] initWithImage:[self scaleImageToSize:[UIImage imageNamed:@"ico_location_up"]  size:CGSizeMake(20, 26)] style:UIBarButtonItemStyleBordered target:self action:@selector(do)];

    self.navigationItem.leftBarButtonItem = cameraItem;

//修改图片大小和控件一致

- (UIImage *)scaleImageToSize:(UIImage *)img size:(CGSize)size

{

    UIGraphicsBeginImageContext(size);

    [img drawInRect:CGRectMake(0, 0, size.width, size.height)];

    UIImage* scaledImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return scaledImage;

}