创建文本视图时:
文本("你好世界")
我不能允许用户在长按时 Select 文本.
我已经考虑过使用文本字段,但这似乎不允许关闭文本编辑.
我只希望能够显示文本主体,并允许用户使用系统文本 Select 器突出显示所选内容.
谢谢
创建文本视图时:
文本("你好世界")
我不能允许用户在长按时 Select 文本.
我已经考虑过使用文本字段,但这似乎不允许关闭文本编辑.
我只希望能够显示文本主体,并允许用户使用系统文本 Select 器突出显示所选内容.
谢谢
从Xcode 13.0 beta 2
开始,你可以使用
Text("Selectable text")
.textSelection(.enabled)
Text("Non selectable text")
.textSelection(.disabled)
// applying `textSelection` to a container
// enables text selection for all `Text` views inside it
VStack {
Text("Selectable text1")
Text("Selectable text2")
// disable selection only for this `Text` view
Text("Non selectable text")
.textSelection(.disabled)
}.textSelection(.enabled)
另见textSelection Documentation.
使用TextField("", text: .constant("Some text"))
有两个问题:
cut
、paste
和其他项目中点击can change the text,而不管使用.constant(...)
我解决这个问题的方法是将UITextField
子类化,并使用UIViewRepresentable
在UIKit
和SwiftUI
之间架起桥梁.
At the end I provide the full code to copy and paste into a playground in Xcode 11.3 on macOS 10.14
将UITextField
分类:
/// This subclass is needed since we want to customize the cursor and the context menu
class CustomUITextField: UITextField, UITextFieldDelegate {
/// (Not used for this workaround, see below for the full code) Binding from the `CustomTextField` so changes of the text can be observed by `SwiftUI`
fileprivate var _textBinding: Binding<String>!
/// If it is `true` the text field behaves normally.
/// If it is `false` the text cannot be modified only selected, copied and so on.
fileprivate var _isEditable = true {
didSet {
// set the input view so the keyboard does not show up if it is edited
self.inputView = self._isEditable ? nil : UIView()
// do not show autocorrection if it is not editable
self.autocorrectionType = self._isEditable ? .default : .no
}
}
// change the cursor to have zero size
override func caretRect(for position: UITextPosition) -> CGRect {
return self._isEditable ? super.caretRect(for: position) : .zero
}
// override this method to customize the displayed items of 'UIMenuController' (the context menu when selecting text)
override func canPerformAction(_ action: Selector, withSender sender: Any?) -> Bool {
// disable 'cut', 'delete', 'paste','_promptForReplace:'
// if it is not editable
if (!_isEditable) {
switch action {
case #selector(cut(_:)),
#selector(delete(_:)),
#selector(paste(_:)):
return false
default:
// do not show 'Replace...' which can also replace text
// Note: This selector is private and may change
if (action == Selector("_promptForReplace:")) {
return false
}
}
}
return super.canPerformAction(action, withSender: sender)
}
// === UITextFieldDelegate methods
func textFieldDidChangeSelection(_ textField: UITextField) {
// update the text of the binding
self._textBinding.wrappedValue = textField.text ?? ""
}
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
// Allow changing the text depending on `self._isEditable`
return self._isEditable
}
}
用UIViewRepresentable
实现SelectableText
struct SelectableText: UIViewRepresentable {
private var text: String
private var selectable: Bool
init(_ text: String, selectable: Bool = true) {
self.text = text
self.selectable = selectable
}
func makeUIView(context: Context) -> CustomUITextField {
let textField = CustomUITextField(frame: .zero)
textField.delegate = textField
textField.text = self.text
textField.setContentHuggingPriority(.defaultHigh, for: .vertical)
textField.setContentHuggingPriority(.defaultHigh, for: .horizontal)
return textField
}
func updateUIView(_ uiView: CustomUITextField, context: Context) {
uiView.text = self.text
uiView._textBinding = .constant(self.text)
uiView._isEditable = false
uiView.isEnabled = self.selectable
}
func selectable(_ selectable: Bool) -> SelectableText {
return SelectableText(self.text, selectable: selectable)
}
}
在下面的完整代码中,我还实现了一个CustomTextField
,其中编辑可以关闭,但仍然可以 Select .
Playground view
Code
import PlaygroundSupport
import SwiftUI
/// This subclass is needed since we want to customize the cursor and the context menu
class CustomUITextField: UITextField, UITextFieldDelegate {
/// Binding from the `CustomTextField` so changes of the text can be observed by `SwiftUI`
fileprivate var _textBinding: Binding<String>!
/// If it is `true` the text field behaves normally.
/// If it is `false` the text cannot be modified only selected, copied and so on.
fileprivate var _isEditable = true {
didSet {
// set the input view so the keyboard does not show up if it is edited
self.inputView = self._isEditable ? nil : UIView()
// do not show autocorrection if it is not editable
self.autocorrectionType = self._isEditable ? .default : .no
}
}
// change the cursor to have zero size
override func caretRect(for position: UITextPosition) -> CGRect {
return self._isEditable ? super.caretRect(for: position) : .zero
}
// override this method to customize the displayed items of 'UIMenuController' (the context menu when selecting text)
override func canPerformAction(_ action: Selector, withSender sender: Any?) -> Bool {
// disable 'cut', 'delete', 'paste','_promptForReplace:'
// if it is not editable
if (!_isEditable) {
switch action {
case #selector(cut(_:)),
#selector(delete(_:)),
#selector(paste(_:)):
return false
default:
// do not show 'Replace...' which can also replace text
// Note: This selector is private and may change
if (action == Selector("_promptForReplace:")) {
return false
}
}
}
return super.canPerformAction(action, withSender: sender)
}
// === UITextFieldDelegate methods
func textFieldDidChangeSelection(_ textField: UITextField) {
// update the text of the binding
self._textBinding.wrappedValue = textField.text ?? ""
}
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
// Allow changing the text depending on `self._isEditable`
return self._isEditable
}
}
struct CustomTextField: UIViewRepresentable {
@Binding private var text: String
private var isEditable: Bool
init(text: Binding<String>, isEditable: Bool = true) {
self._text = text
self.isEditable = isEditable
}
func makeUIView(context: UIViewRepresentableContext<CustomTextField>) -> CustomUITextField {
let textField = CustomUITextField(frame: .zero)
textField.delegate = textField
textField.text = self.text
textField.setContentHuggingPriority(.defaultHigh, for: .vertical)
return textField
}
func updateUIView(_ uiView: CustomUITextField, context: UIViewRepresentableContext<CustomTextField>) {
uiView.text = self.text
uiView._textBinding = self.$text
uiView._isEditable = self.isEditable
}
func isEditable(editable: Bool) -> CustomTextField {
return CustomTextField(text: self.$text, isEditable: editable)
}
}
struct SelectableText: UIViewRepresentable {
private var text: String
private var selectable: Bool
init(_ text: String, selectable: Bool = true) {
self.text = text
self.selectable = selectable
}
func makeUIView(context: Context) -> CustomUITextField {
let textField = CustomUITextField(frame: .zero)
textField.delegate = textField
textField.text = self.text
textField.setContentHuggingPriority(.defaultHigh, for: .vertical)
textField.setContentHuggingPriority(.defaultHigh, for: .horizontal)
return textField
}
func updateUIView(_ uiView: CustomUITextField, context: Context) {
uiView.text = self.text
uiView._textBinding = .constant(self.text)
uiView._isEditable = false
uiView.isEnabled = self.selectable
}
func selectable(_ selectable: Bool) -> SelectableText {
return SelectableText(self.text, selectable: selectable)
}
}
struct TextTestView: View {
@State private var selectableText = true
var body: some View {
VStack {
// Even though the text should be constant, it is not because the user can select and e.g. 'cut' the text
TextField("", text: .constant("Test SwiftUI TextField"))
.background(Color(red: 0.5, green: 0.5, blue: 1))
// This view behaves like the `SelectableText` however the layout behaves like a `TextField`
CustomTextField(text: .constant("Test `CustomTextField`"))
.isEditable(editable: false)
.background(Color.green)
// A non selectable normal `Text`
Text("Test SwiftUI `Text`")
.background(Color.red)
// A selectable `text` where the selection ability can be changed by the button below
SelectableText("Test `SelectableText` maybe selectable")
.selectable(self.selectableText)
.background(Color.orange)
Button(action: {
self.selectableText.toggle()
}) {
Text("`SelectableText` can be selected: \(self.selectableText.description)")
}
// A selectable `text` which cannot be changed
SelectableText("Test `SelectableText` always selectable")
.background(Color.yellow)
}.padding()
}
}
let viewController = UIHostingController(rootView: TextTestView())
viewController.view.frame = CGRect(x: 0, y: 0, width: 400, height: 200)
PlaygroundPage.current.liveView = viewController.view