UITabBar自定义无法按预期工作

Question

我有一个三个标签UITabBar，其中设置了每个标签的背景，以及标签栏本身的背景，如下面第一张图所示。每个UITabBarItem都设置了FinishedSelectedImage和FinishedUnselectedImage，标题为NSString。这些图像是字形（图标）。

但是，将selectionIndicatorImage设置为尺寸为106x48像素的图像，当处于选定状态时，第三个标签右侧有~1像素空间（见第二张照片）。

请告诉我如何删除额外空间？我尝试使用宽1px的图像，但没有区别。

编辑---我读到这可能是一个问题，因为尺寸不正确的selectionIndicatorImage，但我可以确认这不是一个修复 - 我尝试使用107x49px图像，这也没有什么区别。

最大

标签栏（如何选择）

标签栏（如何显示在第三个标签上 - 注意右侧的1px）

// customise the UITabBar - set the background image and the selected background image
[self.tabBarController.tabBar setBackgroundImage:[UIImage imageNamed:@"tab_bar"]];
[self.tabBarController.tabBar setSelectionIndicatorImage:[UIImage imageNamed:@"tabbar_selection_bg_3"]];


// this is in a for loop.
UITabBarItem *item = [[UITabBarItem alloc] init];
[item setTitle:[titles objectAtIndex:index]];
[item setImage:[UIImage imageNamed:[image_titles objectAtIndex:index]]];
[item setFinishedSelectedImage:[UIImage imageNamed:[[image_titles objectAtIndex:index] stringByAppendingString:@"_selected"]] withFinishedUnselectedImage:[UIImage imageNamed:[image_titles objectAtIndex:index]]];
[navigationController setTabBarItem:item];
[item release];

Answer 1

我最后使用三个UITabBarController作为每个标签UIImageViews进行子类化selectionIndicatorBackground，然后使用另一个UIImageView显示标签的字形，并使用UILabel显示其标签标题。

以下是代码：

@interface LPTabBarController : UITabBarController

@property (nonatomic, retain) UIImageView *firstTab, *secondTab, *thirdTab, *firstTabBG, *secondTabBG, *thirdTabBG;
@property (nonatomic, retain) UILabel *firstTabLabel, *secondTabLabel, *thirdTabLabel;

@end


@implementation LPTabBarController

@synthesize firstTab, secondTab, thirdTab, firstTabBG, secondTabBG, thirdTabBG, firstTabLabel, secondTabLabel, thirdTabLabel;

- (id) init {

    if ((self = [super init])) {

        [self initialise];

    }

    return self;

}

- (void) setViewControllers:(NSArray *)viewControllers {

    [self setViewControllers:viewControllers animated:NO];

}

- (void) setViewControllers:(NSArray *)viewControllers animated:(BOOL)animated {

    [super setViewControllers:viewControllers animated:animated];

    for (UITabBarItem *item in self.tabBar.items) {

        [item setEnabled:NO];

    }

}

- (void) initialise {

    UIImageView *bg = [[UIImageView alloc] initWithFrame:CGRectMake(0, self.tabBar.frame.origin.y - 10, 320, 59)];
    [bg setUserInteractionEnabled:YES];
    [bg setImage:[UIImage imageNamed:@"tab_bar"]];

    CGFloat widthbg   = ceilf(self.view.frame.size.width / 3);
    CGFloat heightbg  = self.tabBar.frame.size.height;
    CGFloat width = 23, y = 5;

    UITapGestureRecognizer *gest = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapped:)];

    self.firstTab = [[[UIImageView alloc] initWithImage:[UIImage imageNamed:@"tab_bar_user"]] autorelease];
    [self.firstTab setFrame:CGRectMake(ceilf((widthbg - width) / 2), y, 23, 23)];

    self.firstTabLabel = [[[UILabel alloc] initWithFrame:CGRectMake(0, 27, widthbg, 20)] autorelease];
    [self.firstTabLabel setTextAlignment:NSTextAlignmentCenter];
    [self.firstTabLabel setText:@"Profile"];
    [self.firstTabLabel setFont:[UIFont boldSystemFontOfSize:13]];
    [self.firstTabLabel setTextColor:RGB(80, 23, 17)];
    [self.firstTabLabel setShadowColor:[UIColor colorWithWhite:1 alpha:0.35]];
    [self.firstTabLabel setShadowOffset:CGSizeMake(0, 1)];
    [self.firstTabLabel setBackgroundColor:[UIColor clearColor]];

    self.firstTabBG = [[[UIImageView alloc] initWithImage:nil] autorelease];
    [self.firstTabBG setTag:01];
    [self.firstTabBG setFrame:CGRectMake(0, 10, widthbg, heightbg)];
    [self.firstTabBG addSubview:self.firstTab];
    [self.firstTabBG addSubview:self.firstTabLabel];
    [self.firstTabBG setUserInteractionEnabled:YES];
    [self.firstTabBG addGestureRecognizer:gest];
    [bg addSubview:self.firstTabBG];

    [gest release];

    gest = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapped:)];

    self.secondTab = [[[UIImageView alloc] initWithImage:[UIImage imageNamed:@"tab_bar_explore_selected"]] autorelease];
    [self.secondTab setFrame:CGRectMake(ceilf((widthbg - width) / 2), y, 23, 23)];

    self.secondTabLabel = [[[UILabel alloc] initWithFrame:CGRectMake(0, 27, widthbg, 20)] autorelease];
    [self.secondTabLabel setTextAlignment:NSTextAlignmentCenter];
    [self.secondTabLabel setText:@"Explore"];
    [self.secondTabLabel setFont:[UIFont boldSystemFontOfSize:13]];
    [self.secondTabLabel setTextColor:RGB(80, 23, 17)];
    [self.secondTabLabel setShadowColor:[UIColor colorWithWhite:1 alpha:0.35]];
    [self.secondTabLabel setShadowOffset:CGSizeMake(0, 1)];
    [self.secondTabLabel setBackgroundColor:[UIColor clearColor]];

    self.secondTabBG = [[[UIImageView alloc] initWithImage:[UIImage imageNamed:@"tab_bar_selected_bg"]] autorelease];
    [self.secondTabBG setTag:02];
    [self.secondTabBG setUserInteractionEnabled:YES];
    [self.secondTabBG addGestureRecognizer:gest];
    [self.secondTabBG setFrame:CGRectMake(widthbg, 10, widthbg, heightbg)];
    [self.secondTabBG addSubview:self.secondTab];
    [self.secondTabBG addSubview:self.secondTabLabel];
    [bg addSubview:self.secondTabBG];

    [self tapped:gest];
    [gest release];

    gest = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapped:)];

    self.thirdTab = [[[UIImageView alloc] initWithImage:[UIImage imageNamed:@"tab_bar_settings"]] autorelease];
    [self.thirdTab setFrame:CGRectMake(ceilf((widthbg - width) / 2), y, 23, 23)];

    self.thirdTabLabel = [[[UILabel alloc] initWithFrame:CGRectMake(0, 27, widthbg, 20)] autorelease];
    [self.thirdTabLabel setTextAlignment:NSTextAlignmentCenter];
    [self.thirdTabLabel setText:@"Settings"];
    [self.thirdTabLabel setFont:[UIFont boldSystemFontOfSize:13]];
    [self.thirdTabLabel setTextColor:RGB(80, 23, 17)];
    [self.thirdTabLabel setShadowColor:[UIColor colorWithWhite:1 alpha:0.35]];
    [self.thirdTabLabel setShadowOffset:CGSizeMake(0, 1)];
    [self.thirdTabLabel setBackgroundColor:[UIColor clearColor]];

    self.thirdTabBG = [[[UIImageView alloc] initWithImage:nil] autorelease];
    [self.thirdTabBG setTag:03];
    [self.thirdTabBG setFrame:CGRectMake(widthbg * 2, 10, widthbg, heightbg)];
    [self.thirdTabBG addSubview:self.thirdTab];
    [self.thirdTabBG addSubview:self.thirdTabLabel];
    [self.thirdTabBG setUserInteractionEnabled:YES];
    [self.thirdTabBG addGestureRecognizer:gest];
    [bg addSubview:self.thirdTabBG];
    [gest release];

    [self.view addSubview:bg];
    [bg release];

}

static int lastIndex = 2;

- (void) tapped:(UITapGestureRecognizer *) gest {

    switch (lastIndex) {
        case 1:
            [self.firstTab setImage:[UIImage imageNamed:@"tab_bar_user"]];
            [self.firstTabBG setImage:nil];
            [self.firstTabLabel setTextColor:RGB(80, 23, 17)];
            [self.firstTabLabel setShadowColor:[UIColor colorWithWhite:1 alpha:0.35]];
            [self.firstTabLabel setShadowOffset:CGSizeMake(0, 1)];
            break;

        case 2:
            [self.secondTab setImage:[UIImage imageNamed:@"tab_bar_explore"]];
            [self.secondTabBG setImage:nil];
            [self.secondTabLabel setTextColor:RGB(80, 23, 17)];
            [self.secondTabLabel setShadowColor:[UIColor colorWithWhite:1 alpha:0.35]];
            [self.secondTabLabel setShadowOffset:CGSizeMake(0, 1)];

            break;

        case 3:
            [self.thirdTab setImage:[UIImage imageNamed:@"tab_bar_settings"]];
            [self.thirdTabBG setImage:nil];
            [self.thirdTabLabel setTextColor:RGB(80, 23, 17)];
            [self.thirdTabLabel setShadowColor:[UIColor colorWithWhite:1 alpha:0.35]];
            [self.thirdTabLabel setShadowOffset:CGSizeMake(0, 1)];
            break;
    }

    switch (gest.view.tag) {
        case 1 :{

            [self setSelectedIndex:0];
            [self.firstTab setImage:[UIImage imageNamed:@"tab_bar_user_selected"]];
            [self.firstTabBG setImage:[UIImage imageNamed:@"tab_bar_selected_bg"]];
            [self.firstTabLabel setTextColor:RGB(252, 208, 170)];
            [self.firstTabLabel setShadowColor:RGB(80, 23, 17)];
            [self.firstTabLabel setShadowOffset:CGSizeMake(0, -1)];

            break;

        }

        case 2: {

            [self setSelectedIndex:1];
            [self.secondTab setImage:[UIImage imageNamed:@"tab_bar_explore_selected"]];
            [self.secondTabBG setImage:[UIImage imageNamed:@"tab_bar_selected_bg"]];
            [self.secondTabLabel setTextColor:RGB(252, 208, 170)];
            [self.secondTabLabel setShadowColor:RGB(80, 23, 17)];
            [self.secondTabLabel setShadowOffset:CGSizeMake(0, -1)];
            break;

        }

        case 3: {

            [self setSelectedIndex:2];
            [self.thirdTab setImage:[UIImage imageNamed:@"tab_bar_settings_selected"]];
            [self.thirdTabBG setImage:[UIImage imageNamed:@"tab_bar_selected_bg"]];
            [self.thirdTabLabel setTextColor:RGB(252, 208, 170)];
            [self.thirdTabLabel setShadowColor:RGB(80, 23, 17)];
            [self.thirdTabLabel setShadowOffset:CGSizeMake(0, -1)];
            break;

        }
    }

    lastIndex = gest.view.tag;

}

- (void) dealloc {

    [firstTab release];
    [firstTabBG release];
    [secondTab release];
    [secondTabBG release];
    [thirdTab release];
    [thirdTabBG release];
    [firstTabLabel release];
    [secondTabLabel release];
    [thirdTabLabel release];
    [super dealloc];

}