Ios 如何在不同设备的segment控制中管理文本大小(text size)

下面是我能想到的一种方法，但绝不是唯一的方法.

首先，我设置了一个带有水平流布局的集合视图.

// Flow layout configuration, mainly to figure out width of the cells
private func createLayout() -> UICollectionViewFlowLayout {
    
    let flowLayout = UICollectionViewFlowLayout()
    flowLayout.minimumLineSpacing = horizontalPadding
    flowLayout.minimumInteritemSpacing = 0
    flowLayout.scrollDirection = .horizontal
    
    // Calculate the available width to divide the segments evenly
    var availableWidth = UIScreen.main.bounds.width
    
    // There will always be segments - 1 gaps, for 3 segments, there will be
    // 2 gaps and for 4 segments there will be 3 gaps etc
    availableWidth -= horizontalPadding * CGFloat(segments.count - 1)
    
    let cellWidth = availableWidth / CGFloat(segments.count)
    
    flowLayout.itemSize = CGSize(width: cellWidth,
                                 height: collectionViewHeight)
    
    return flowLayout
}

一旦我这么做了，我就会遇到同样的问题，根据屏幕的宽度，我的文本可能会被切断.

所以一旦确定了每段的宽度，我们就必须计算出maximum font size to show the complete text for the longest segment and that font size should be applied to all

在这种情况下，长段的字符串长度为Vibration Intensity.

// Flow layout configuration, mainly to figure out width of the cells
private func createLayout() -> UICollectionViewFlowLayout {
    
    let flowLayout = UICollectionViewFlowLayout()
    flowLayout.minimumLineSpacing = horizontalPadding
    flowLayout.minimumInteritemSpacing = 0
    flowLayout.scrollDirection = .horizontal
    flowLayout.sectionInset = UIEdgeInsets(top: 0,
                                           left: horizontalPadding,
                                           bottom: 0,
                                           right: horizontalPadding)
    
    // Calculate the available width to divide the segments evenly
    var availableWidth = UIScreen.main.bounds.width
    
    // There will always be segments - 1 gaps, for 3 segments, there will be
    // 2 gaps and for 4 segments there will be 3 gaps etc
    availableWidth -= horizontalPadding * CGFloat(segments.count - 1)
    
    // Remove the insets
    availableWidth -= flowLayout.sectionInset.left + flowLayout.sectionInset.right
    
    let cellWidth = availableWidth / CGFloat(segments.count)
    
    // Add this function
    calculateApproxFontSize(forWidth: cellWidth)
    
    flowLayout.itemSize = CGSize(width: cellWidth,
                                 height: collectionViewHeight)
    
    return flowLayout
}

private func calculateApproxFontSize(forWidth width: CGFloat) {
    
    // Get the longest segment by length
    if let longestSegmentTitle = segments.max(by: { $1.count > $0.count }) {
        
        let tempLabel = UILabel()
        tempLabel.numberOfLines = 1
        tempLabel.text = longestSegmentTitle
        tempLabel.sizeToFit()
        
        guard var currentFont = tempLabel.font else { return }
        
        var intrinsicSize
            = (longestSegmentTitle as NSString).size(withAttributes: [.font : currentFont])
        
        // Keep looping and reduce the font size till the text
        // fits into the label
        // This could be optimized further using binary search
        // However this should be ok for small strings
        while intrinsicSize.width > width
        {
            currentFont = currentFont.withSize(currentFont.pointSize - 1)
            tempLabel.font = currentFont
            
            intrinsicSize
                = (longestSegmentTitle as NSString).size(withAttributes: [.font : currentFont])
        }

        // Set the font of the current label
        // segmentFontSize is a global var in the VC
        segmentFontSize = currentFont.pointSize
    }
}

然后在cellForItemAt indexPath中设置segmentFontSize

func collectionView(_ collectionView: UICollectionView,
                    cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    
    let cell = collectionView
        .dequeueReusableCell(withReuseIdentifier: SegmentCell.reuseIdentifier,
                             for: indexPath) as! SegmentCell
    
    cell.backgroundColor = .orange
    cell.title.text = segments[indexPath.item]
    
    // Adjust the font
    cell.title.font = cell.title.font.withSize(segmentFontSize)
    
    return cell
}

这会给你类似的东西:

如果你发现某些部分很难理解，下面是完整代码的链接:https://gist.github.com/shawn-frank/03bc06d13f90a54e23e9ea8c6f30a70e