ios - SpriteKit touchesBegan 和 didBeginContact

Question

我知道如何检测两个物体何时接触，并且我知道如何检测屏幕何时被触摸。但是，如果我想知道两个物体接触时屏幕是否被触摸怎么办？如果触摸发生在接触之前，但在接触期间则不起作用，touchesBegan 上的 bool 标志有效。

var screenTouch = false

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        for _ in touches {
            screenTouch = true
        }
    }

func didBegin(_ contact: SKPhysicsContact) {

    let collision = contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask

    switch collision {
    case PhysicsCategories.Ball | PhysicsCategories.Edge:

        if screenTouch {
            print("LAUNCH!")
        }
etc.

Answer 1

您必须创建一个条件变量，该条件变量在 didBegin 时为 true，在 didEnd 时为 false。在您的 touchesBegin 中，当条件变量为 true 时完成您的操作。

var yourBodiesInContact = false

func didBegin(_ contact: SKPhysicsContact) {

    let collision = contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask

    if collision == PhysicsCategory.Ball | PhysicsCategory.Edge {
        yourBodiesInContact = true
    }
}

func didEnd(_ contact: SKPhysicsContact) {
    let collision = contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask

    if collision == PhysicsCategory.Ball | PhysicsCategory.Edge {
        yourBodiesInContact = false
    }
}

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    if yourBodiesInContact {
       // while in contact
    } else {
       // ...
    }
}