在 NSView 中以编程方式创建 NSScrollView - Cocoa

Question

我有一个 NSView 类，它负责在 nib 文件中创建的自定义视图。

现在我想将 NSScrollView 添加到自定义视图中，但我需要以编程方式完成，而不是使用 Interface Builder（嵌入到滚动视图中）。

我找到了这段代码：

NSView *windowContentView = [mainWindow contentView];
NSRect windowContentBounds = [windowContentView bounds];
scrollView = [[NSScrollView alloc] init];
[scrollView setBorderType:NSNoBorder];
[scrollView setHasVerticalScroller:YES];
[scrollView setBounds: windowContentBounds];
[windowContentView addSubview:scrollView];

假设我将上面的变量“mainWindow”和“scrollView”声明为 IBOutlets，我将如何将它们连接到 Interface Builder 中的适当组件？这样做有意义吗？

或者有没有更好的方式以编程方式添加滚动视图？

附：我无法以通常的方式连接它们，因为我无法从 Interface Builder 创建一个 NSObject 对象，也无法使用 File Owner..

Answer 1

我很难以编程方式使用AutoLayout 创建NSScrollView，但最终让它工作。这是Swift 版本。

// Initial scrollview
let scrollView = NSScrollView()
scrollView.translatesAutoresizingMaskIntoConstraints = false
scrollView.borderType = .noBorder
scrollView.backgroundColor = NSColor.gray
scrollView.hasVerticalScroller = true

window.contentView?.addSubview(scrollView)
window.contentView?.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[scrollView]|", options: [], metrics: nil, views: ["scrollView": scrollView]))
window.contentView?.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|[scrollView]|", options: [], metrics: nil, views: ["scrollView": scrollView]))

// Initial clip view
let clipView = NSClipView()
clipView.translatesAutoresizingMaskIntoConstraints = false
scrollView.contentView = clipView
scrollView.addConstraint(NSLayoutConstraint(item: clipView, attribute: .left, relatedBy: .equal, toItem: scrollView, attribute: .left, multiplier: 1.0, constant: 0))
scrollView.addConstraint(NSLayoutConstraint(item: clipView, attribute: .top, relatedBy: .equal, toItem: scrollView, attribute: .top, multiplier: 1.0, constant: 0))
scrollView.addConstraint(NSLayoutConstraint(item: clipView, attribute: .right, relatedBy: .equal, toItem: scrollView, attribute: .right, multiplier: 1.0, constant: 0))
scrollView.addConstraint(NSLayoutConstraint(item: clipView, attribute: .bottom, relatedBy: .equal, toItem: scrollView, attribute: .bottom, multiplier: 1.0, constant: 0))

// Initial document view
let documentView = NSView()
documentView.translatesAutoresizingMaskIntoConstraints = false
scrollView.documentView = documentView
clipView.addConstraint(NSLayoutConstraint(item: clipView, attribute: .left, relatedBy: .equal, toItem: documentView, attribute: .left, multiplier: 1.0, constant: 0))
clipView.addConstraint(NSLayoutConstraint(item: clipView, attribute: .top, relatedBy: .equal, toItem: documentView, attribute: .top, multiplier: 1.0, constant: 0))
clipView.addConstraint(NSLayoutConstraint(item: clipView, attribute: .right, relatedBy: .equal, toItem: documentView, attribute: .right, multiplier: 1.0, constant: 0))

// Subview1
let view1 = NSView()
view1.translatesAutoresizingMaskIntoConstraints = false
view1.wantsLayer = true
view1.layer?.backgroundColor = NSColor.red.cgColor
documentView.addSubview(view1)
documentView.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[view1]|", options: [], metrics: nil, views: ["view1": view1]))

// Subview2
let view2 = NSView()
view2.translatesAutoresizingMaskIntoConstraints = false
view2.wantsLayer = true
view2.layer?.backgroundColor = NSColor.green.cgColor
documentView.addSubview(view2)
documentView.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[view2]|", options: [], metrics: nil, views: ["view2": view2]))

// Subview3
let view3 = NSView()
view3.translatesAutoresizingMaskIntoConstraints = false
view3.wantsLayer = true
view3.layer?.backgroundColor = NSColor.blue.cgColor
documentView.addSubview(view3)
documentView.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[view3]|", options: [], metrics: nil, views: ["view3": view3]))

// Vertical autolayout
documentView.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|[view1(==100)][view2(==200)][view3(==300)]", options: [], metrics: nil, views: ["view1": view1, "view2": view2, "view3": view3]))
documentView.addConstraint(NSLayoutConstraint(item: documentView, attribute: .bottom, relatedBy: .equal, toItem: view3, attribute: .bottom, multiplier: 1.0, constant: 0))

Answer 2

此代码片段应演示如何以编程方式创建 NSScrollView 并使用它来显示任何视图，无论是来自 nib 还是来自代码。在 nib 生成视图的情况下，您只需事先将 nib 文件加载到您的自定义视图中，然后将您的自定义视图的出口 (outletToCustomViewLoadedFromNib) 设置为文件的所有者。

NSScrollView *scrollView = [[NSScrollView alloc] initWithFrame:[[mainWindow contentView] frame]];

// configure the scroll view
[scrollView setBorderType:NSNoBorder];
[scrollView setHasVerticalScroller:YES];

// embed your custom view in the scroll view
[scrollView setDocumentView:outletToCustomViewLoadedFromNib];

// set the scroll view as the content view of your window
[mainWindow setContentView:scrollView];

Apple 有一个关于这个主题的指南，我不会链接到它，因为它需要 Apple Developer Connection 访问权限，并且他们的链接经常断开。它的标题是“创建和配置滚动视图”，目前可以通过使用 Google 搜索其标题来找到。

Answer 3

Brian 的回答是正确的，这里是如何在 Swift 4.2 中的 NSScrollView 中创建 NSStackView

见https://github.com/onmyway133/blog/issues/173

您可能需要翻转NSClipView

final class FlippedClipView: NSClipView {
  override var isFlipped: Bool {
    return true
  }
}


private func setup() {
  setupScrollView()
  setupStackView()
}

private func setupScrollView() {
  view.addSubview(scrollView)
  scrollView.translatesAutoresizingMaskIntoConstraints = false
  scrollView.hasVerticalScroller = true
  scrollView.drawsBackground = false

  NSLayoutConstraint.activate([
    scrollView.leftAnchor.constraint(equalTo: view.leftAnchor),
    scrollView.rightAnchor.constraint(equalTo: view.rightAnchor),
    scrollView.topAnchor.constraint(equalTo: view.topAnchor),
    scrollView.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -30),

    scrollView.heightAnchor.constraint(equalToConstant: 400)
  ])

  let clipView = FlippedClipView()
  clipView.drawsBackground = false
  scrollView.contentView = clipView
  clipView.translatesAutoresizingMaskIntoConstraints = false
  NSLayoutConstraint.activate([
    clipView.leftAnchor.constraint(equalTo: scrollView.leftAnchor),
    clipView.rightAnchor.constraint(equalTo: scrollView.rightAnchor),
    clipView.topAnchor.constraint(equalTo: scrollView.topAnchor),
    clipView.bottomAnchor.constraint(equalTo: scrollView.bottomAnchor)
  ]
  scrollView.documentView = stackView

  stackView.translatesAutoresizingMaskIntoConstraints = false
  NSLayoutConstraint.activate([
    stackView.leftAnchor.constraint(equalTo: clipView.leftAnchor),
    stackView.topAnchor.constraint(equalTo: clipView.topAnchor),
    stackView.rightAnchor.constraint(equalTo: clipView.rightAnchor),
    // NOTE: No need for bottomAnchor
  ])
}

private func setupStackView() {
  stackView.orientation = .vertical
  stackView.edgeInsets = NSEdgeInsets(top: 16, left: 16, bottom: 16, right: 16)

  NSLayoutConstraint.activate([
    myRowView.heightAnchor.constraint(equalToConstant: 40)
  ])

  myRowView.onPress = { [weak self] in
    self?.doSomething()
  }

  stackView.addArrangedSubview(myRowView)
}

Answer 4

这是一个将NSStackView 以编程方式添加到NSScrollView 的示例。可以使用以下解决方案添加任何视图，但我以 NSStackView 为例

我使用SnapKit 来保持自动布局代码简洁，但是，您可以使用锚来添加约束，而无需任何第三方依赖

// Create NSScrollView and add it as a subview in the desired location
let scrollView = NSScrollView()
scrollView.borderType = .noBorder
scrollView.verticalScrollElasticity = .none
addSubview(scrollView)
scrollView.snp.makeConstraints { $0.edges.equalToSuperview() } //match edges to superview

// Assign an instance of NSClipView to `contentView` property of `NSScrollView`
let clipView = NSClipView()
scrollView.contentView = clipView
clipView.snp.makeConstraints { $0.edges.equalTo(scrollView) }

// Assign whatever view you want to put inside scroll view to the `documentView` property.
// Also note I have added just 3 constraints; top bottom and left. That way stackview can freely expand on the right
scrollView.documentView = stackView
stackView.snp.makeConstraints { $0.top.bottom.left.equalTo(clipView) }

请注意，在添加子视图后我没有使用translatesAutoresizingMaskIntoConstraints，因为 SnapKit 在内部处理它，但如果您使用锚添加约束，请确保所有以编程方式添加的子视图都将 translatesAutoresizingMaskIntoConstraints 设置为 false。