如何为 NavigationLink 设置条件？ 斯威夫特

Question

I would like to put a condition to the NavigationLink.

I have two variable, and the NavigationLink as below.

  @State var score = 0
  @State var target = 10

NavigationLink(destination: level2()) {     
  Text("Next Level")
 }

Is there a way to let the user go to the next level if the score is bigger than the target?

Thanks.

Answer 1

Well, your question can be interpreted differently...

1) if you want to don't show the ability to go next until score is bigger that target at all, then it is

if score > target { // link will appear to user only when true
  NavigationLink(destination: level2()) {     
    Text("Next Level")
  }
}

2) if you want to show link but don't allow to navigate until condition is true, then it is

  NavigationLink(destination: level2()) {     
    Text("Next Level")
  }.disabled(score <= target)

3) if you want automatically navigate link when condition is true, then the possible variant is ( but note - in such case you need manually manipulate back-forward navigation, or disallow back, etc. )

  NavigationLink(destination: level2(), isActive: .constant(score > target)) {     
    Text("Next Level")
  }

• alternate is to use explicit state for activation

Answer 2

In case you want to keep the color and present some alert when you tap you can use below hack:

NavigationLink(destination: EmptyView()) {
                HStack {
                    Circle()
  }
}
            .contentShape(Rectangle())
            .onTapGesture {
                print("ALERT MAYBE")
            }