在 UINavigationController 中添加带有标题的图像

Question

我想在 UINavigationController 的标题旁边显示一个小图标。

通过 Photoshop 的魔力，像这样：

我知道我需要创建一个新视图并将图像和标题构建到其中。这是我正在做的事情：

在UINavigationController视图控制器的viewDidLoad中，我调用了方法

[self setTitleBar];

调用此方法：

- (void) setTitleBar {


    CGRect navBarFrame = self.navigationController.navigationBar.frame;


    //UIView *titleView = [[UIView alloc] initWithFrame:CGRectMake(navBarFrame.origin.x, navBarFrame.origin.y, (leftButtonFrame.origin.x + leftButtonFrame.size.width) - rightButtonFrame.origin.x, navBarFrame.size.height)];
    UIView *titleView = [[UIView alloc] initWithFrame:CGRectMake(navBarFrame.origin.x, navBarFrame.origin.y,self.view.frame.size.width,navBarFrame.size.height)];
    titleView.backgroundColor = [UIColor clearColor];


    CGPoint tvCenter = CGPointMake(titleView.frame.size.width/2, titleView.frame.size.height/2);

    UIImage * icon = [UIImage imageNamed:@"star"];

    UIImageView *iconView = [[UIImageView alloc] initWithImage:icon];
    iconView.frame = CGRectMake(0, 0, icon.size.width, icon.size.height);

    UILabel *title = [[UILabel alloc] init];
    title.backgroundColor = [UIColor clearColor];
    title.textColor = [UIColor whiteColor];
    title.textAlignment = NSTextAlignmentCenter;
    title.text = @"SOME TITLE";
    title.frame = CGRectMake(0, 0, 100, titleView.frame.size.height);
    [title sizeToFit];


    iconView.center = CGPointMake(tvCenter.x - (icon.size.width/2), tvCenter.y);

    [titleView addSubview:iconView];
    [titleView addSubview:title];

    self.navigationItem.titleView = titleView;
}

我在titleView中的逻辑是：获取最左边的按钮框架，获取最右边的按钮框架。然后做一些数学计算来计算视图的大小。那应该是titleView的frame size。

但是，我似乎无法让它工作。如果我插入的帧大小为 0,0,100,40；然后它显示框架，但所有内容都被挤压在一起。但是你看到了。我知道 100 应该是动态的以确保显示标题。

但我似乎无法弄清楚。

有什么帮助吗？

Answer 1

您可以将对象作为子视图放置在导航控制器视图上。

- (void) setTitleBar {

    //Let's say your icon size is 20
    int starSize = 20;
    //Now you'll have to calculate where to place the ImageView respect the TextSize (for this you'll need to know the text and font of your UINavigationItem title)
    CGSize textSize = [@"SOME TITLE" sizeWithAttributes:@{NSFontAttributeName:[UIFont fontWithName:@"navfontname" size:15]}];
    UIImageView *startImageView = [[UIImageView alloc] initWithFrame:CGRectMake(self.navigationController.view.frame.size.width/2 - textSize.width/2, self.navigationController.view.frame.size.height/2 - starSize/2, starSize,starSize)];
    startImageView.image = [UIImage imageNamed:@"star"];
    [self.navigationController.view addSubview:startImageView];

}