我有一個黃色按鈕和一個灰色容器內的藍色圓圈。我
這是我的代碼：
struct ContentView: View {
@GestureState var containerOffset = CGSize.zero
@GestureState var circleOffset = CGSize.zero
var body: some View {
VStack { /// gray container
/// should move the gray container when dragged
Button {
print("Button Pressed")
} label: {
Text("Button")
.padding(50)
.background(.yellow)
}
/// should **NOT** move the gray container when dragged
/// How do I make it move the circle instead?
Circle()
.fill(.blue)
.frame(width: 100, height: 100)
.offset(circleOffset)
.gesture(
DragGesture() /// this never gets called!
.updating($circleOffset) { value, circleOffset, transaction in
circleOffset = value.translation
}
)
.padding(50)
}
.background(Color.gray)
.offset(containerOffset)
.simultaneousGesture( /// `simultaneous` is needed to allow dragging from the yellow button
DragGesture() /// move the gray container
.updating($containerOffset) { value, containerOffset, transaction in
containerOffset = value.translation
}
)
}
}
我如何阻止外圈DragGesture吞下內圈DragGesture？
uj5u.com熱心網友回復：
一種方法是添加一個狀態變數，ContentView用于跟蹤圓圈的手勢是否處于活動狀態。當圓圈的手勢處于活動狀態時，在外部手勢上使用GestureMaskof.subviews以防止其激活。你可以用一個@State：
import SwiftUI
import PlaygroundSupport
struct ContentView: View {
@GestureState var containerOffset = CGSize.zero
@GestureState var circleOffset = CGSize.zero
@State var subviewDragIsActive = false
var body: some View {
VStack { /// gray container
/// should move the gray container when dragged
Button {
print("Button Pressed")
} label: {
Text("Button")
.padding(50)
.background(Color.yellow)
}
/// should **NOT** move the gray container when dragged
/// How do I make it move the circle instead?
Circle()
.fill(Color.blue)
.frame(width: 100, height: 100)
.offset(circleOffset)
.gesture(
DragGesture() /// this never gets called!
.updating($circleOffset) { value, circleOffset, transaction in
circleOffset = value.translation
}
.onChanged { _ in
subviewDragIsActive = true
}
.onEnded { _ in
subviewDragIsActive = false
}
)
.padding(50)
}
.background(Color.gray)
.offset(containerOffset)
.simultaneousGesture( /// `simultaneous` is needed to allow dragging from the yellow button
DragGesture() /// move the gray container
.updating($containerOffset) { value, containerOffset, transaction in
containerOffset = value.translation
},
including: subviewDragIsActive ? .subviews : .all
)
}
}
PlaygroundPage.current.setLiveView(ContentView())
或者你可以用一個@GestureState：
import SwiftUI
import PlaygroundSupport
struct ContentView: View {
@GestureState var containerOffset = CGSize.zero
@GestureState var circleOffset = CGSize.zero
@GestureState var subviewDragIsActive = false
var body: some View {
VStack { /// gray container
/// should move the gray container when dragged
Button {
print("Button Pressed")
} label: {
Text("Button")
.padding(50)
.background(Color.yellow)
}
/// should **NOT** move the gray container when dragged
/// How do I make it move the circle instead?
Circle()
.fill(Color.blue)
.frame(width: 100, height: 100)
.offset(circleOffset)
.gesture(
DragGesture() /// this never gets called!
.updating($circleOffset) { value, circleOffset, transaction in
circleOffset = value.translation
}
.updating($subviewDragIsActive) {
_, flag, _ in
flag = true
}
)
.padding(50)
}
.background(Color.gray)
.offset(containerOffset)
.simultaneousGesture( /// `simultaneous` is needed to allow dragging from the yellow button
DragGesture() /// move the gray container
.updating($containerOffset) { value, containerOffset, transaction in
containerOffset = value.translation
},
including: subviewDragIsActive ? .subviews : .all
)
}
}
PlaygroundPage.current.setLiveView(ContentView())
如果圓是單獨定義的View型別，則應使用 an@State以便向下傳遞 a Binding，如下所示：
import SwiftUI
import PlaygroundSupport
struct CircleView: View {
@GestureState var circleOffset = CGSize.zero
@Binding var dragIsActive: Bool
var body: some View {
Circle()
.fill(Color.blue)
.frame(width: 100, height: 100)
.offset(circleOffset)
.gesture(
DragGesture() /// this never gets called!
.updating($circleOffset) { value, circleOffset, transaction in
circleOffset = value.translation
}
.onChanged { _ in dragIsActive = true }
.onEnded { _ in dragIsActive = false }
)
}
}
struct ContentView: View {
@GestureState var containerOffset = CGSize.zero
@State var subviewDragIsActive = false
var body: some View {
VStack { /// gray container
/// should move the gray container when dragged
Button {
print("Button Pressed")
} label: {
Text("Button")
.padding(50)
.background(Color.yellow)
}
/// should **NOT** move the gray container when dragged
/// How do I make it move the circle instead?
CircleView(dragIsActive: $subviewDragIsActive)
.padding(50)
}
.background(Color.gray)
.offset(containerOffset)
.simultaneousGesture( /// `simultaneous` is needed to allow dragging from the yellow button
DragGesture() /// move the gray container
.updating($containerOffset) { value, containerOffset, transaction in
containerOffset = value.translation
},
including: subviewDragIsActive ? .subviews : .all
)
}
}
PlaygroundPage.current.setLiveView(ContentView())
如果多個子視圖中的任何一個可能同時進行拖動（由于多點觸控），您可能應該使用首選項系統將它們的 isActive 狀態傳遞到ContentView，但這是一個明顯更復雜的實作。
轉載請註明出處，本文鏈接：https://www.uj5u.com/qukuanlian/373020.html