技术问询：无法将KDCircularProgress视图限制在父视图内

Looking at your code, the core issue is that you're creating a KDCircularProgress instance but never adding it as a subview to your custom ProgressView, nor setting up proper layout rules to keep it bounded within the parent. Here's how to resolve this step by step:

Step 1: Update Your Initializer #

Adjust your init(frame:) to use Auto Layout-friendly setup (this avoids hardcoding frames and ensures better adaptability):

init(frame: CGRect) {
    progress = KDCircularProgress(frame: .zero) // Start with empty frame; constraints will handle sizing
    letter = "A"
    super.init(frame: frame)
    setupCircularProgress()
    
    // Configure center label (adjusted for clarity and proper layout)
    let centerLabel = UILabel()
    centerLabel.text = letter
    centerLabel.translatesAutoresizingMaskIntoConstraints = false
    addSubview(centerLabel)
    
    NSLayoutConstraint.activate([
        centerLabel.centerXAnchor.constraint(equalTo: self.centerXAnchor),
        centerLabel.centerYAnchor.constraint(equalTo: self.centerYAnchor)
    ])
}

Step 2: Fix the setupCircularProgress Function #

Modify this function to attach the progress view to your custom view and constrain it to the parent's bounds:

func setupCircularProgress() {
    // Disable auto-generated constraints to avoid conflicts with our custom rules
    progress.translatesAutoresizingMaskIntoConstraints = false
    // Add the progress view to your custom ProgressView's view hierarchy
    addSubview(progress)
    
    // Pin all edges of the progress view to its parent
    NSLayoutConstraint.activate([
        progress.topAnchor.constraint(equalTo: self.topAnchor),
        progress.leadingAnchor.constraint(equalTo: self.leadingAnchor),
        progress.trailingAnchor.constraint(equalTo: self.trailingAnchor),
        progress.bottomAnchor.constraint(equalTo: self.bottomAnchor)
    ])
    
    // Your existing configuration
    progress.clockwise = true
    progress.set(colors: randomColor(...)) // Replace with your actual random color logic
    // Optional: Add extra configs like line width or start angle
    // progress.lineWidth = 12
    // progress.startAngle = -90
}

Why This Works #

• Adding the Subview: Without addSubview(progress), your KDCircularProgress instance isn't part of the view hierarchy, so it won't render correctly (or at all).
• Auto Layout Constraints: By pinning all edges to the parent, you ensure the progress view always stays within the bounds of your ProgressView—even if the parent's size changes (e.g., device rotation, dynamic layout adjustments).
• Disabling translatesAutoresizingMaskIntoConstraints: This prevents iOS from generating automatic constraints that might override your custom layout setup.

If you prefer frame-based layout over Auto Layout, you could replace the constraint block with:

progress.frame = self.bounds

But Auto Layout is recommended for modern iOS apps due to its flexibility across different screen sizes and orientations.

内容的提问来源于stack exchange，提问作者Brenda Wang