ios - UINavigationBar TitleView 带副标题

Question

我想要在我的 UINavigationBar 中有一个 titleView，它有两行文本而不是只有一行

当我有一个“后退”按钮和一个“编辑”按钮时，我当前的实现效果很好，因为它看起来几乎居中。问题是当我只有一个按钮时。它看起来非常奇怪和错误，因为 View 以可用空间为中心。

UINavigationBar with left and right Button

UINavigationBar with only one Button

这是我当前的实现:

CGRect frame = self.navigationController.navigationBar.frame;

UIView *twoLineTitleView = [[UIView alloc] initWithFrame:CGRectMake(CGRectGetWidth(frame), 0, CGRectGetWidth(frame), CGRectGetHeight(frame))];

UILabel *titleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 8, CGRectGetWidth(frame), 14)];
titleLabel.backgroundColor = [UIColor clearColor];
titleLabel.autoresizingMask = UIViewAutoresizingFlexibleWidth;
titleLabel.textAlignment = UITextAlignmentCenter;
titleLabel.text = self.title;
[twoLineTitleView addSubview:titleLabel];

UILabel *subTitleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 23, CGRectGetWidth(frame), 14)];
subTitleLabel.backgroundColor = [UIColor clearColor];
subTitleLabel.autoresizingMask = UIViewAutoresizingFlexibleWidth;
subTitleLabel.textAlignment = UITextAlignmentCenter;
subTitleLabel.text = self.subTitle;
[twoLineTitleView addSubview:subTitleLabel];

self.navigationItem.titleView = twoLineTitleView;

Answer 1

下面是我的做法:

• 为您的两个标签分别使用 sizeToFit。
• 将容器 View 的宽度设置为两个标签的最大宽度。
• 将 View 中两个标签中较小的一个居中。

这段代码应该适合你:

    UILabel *titleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 0, 0)];
    titleLabel.backgroundColor = [UIColor clearColor];
    titleLabel.textColor = [UIColor whiteColor];
    titleLabel.font = [UIFont boldSystemFontOfSize:20];
    titleLabel.text = @"Your Title";
    [titleLabel sizeToFit];

    UILabel *subTitleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 22, 0, 0)];
    subTitleLabel.backgroundColor = [UIColor clearColor];
    subTitleLabel.textColor = [UIColor whiteColor];
    subTitleLabel.font = [UIFont systemFontOfSize:12];
    subTitleLabel.text = @"Your subtitle";
    [subTitleLabel sizeToFit];

    UIView *twoLineTitleView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, MAX(subTitleLabel.frame.size.width, titleLabel.frame.size.width), 30)];
    [twoLineTitleView addSubview:titleLabel];
    [twoLineTitleView addSubview:subTitleLabel];

    float widthDiff = subTitleLabel.frame.size.width - titleLabel.frame.size.width;

    if (widthDiff > 0) {
        CGRect frame = titleLabel.frame;
        frame.origin.x = widthDiff / 2;
        titleLabel.frame = CGRectIntegral(frame);
    }else{
        CGRect frame = subTitleLabel.frame;
        frame.origin.x = abs(widthDiff) / 2;
        subTitleLabel.frame = CGRectIntegral(frame);
    }

    self.navigationItem.titleView = twoLineTitleView;

Swift 3 变体:

    let titleLabel = UILabel.init(frame: CGRect.zero)
    titleLabel.backgroundColor = UIColor.clear
    titleLabel.textColor = UIColor.schBlack
    titleLabel.font = UIFont.schTextStyle2Font()
    titleLabel.text = titleString;
    titleLabel.sizeToFit()

    let subTitleLabel = UILabel.init(frame: CGRect.init(x: 0, y: 22, width: 0, height: 0))
    subTitleLabel.backgroundColor = UIColor.clear
    subTitleLabel.textColor = UIColor.schBrownishGrey
    subTitleLabel.font = UIFont.schTextStyle3Font()
    subTitleLabel.text = subTitleString;
    subTitleLabel.sizeToFit()

    let twoLineTitleView = UIView.init(frame: CGRect.init(x: 0, y: 0, width: self.view.frame.width-40, height: 30))
    twoLineTitleView.addSubview(titleLabel)
    twoLineTitleView.addSubview(subTitleLabel)

    /*

    float widthDiff = subTitleLabel.frame.size.width - titleLabel.frame.size.width;
    if (widthDiff > 0) {
        CGRect frame = titleLabel.frame;
        frame.origin.x = widthDiff / 2;
        titleLabel.frame = CGRectIntegral(frame);
    }else{
        CGRect frame = subTitleLabel.frame;
        frame.origin.x = abs(widthDiff) / 2;
        subTitleLabel.frame = CGRectIntegral(frame);
    }
    */

    self.navigationItem.titleView = twoLineTitleView;