Touchesmoved

Question

我正在尝试通过单击并拖动元素来更新多个图像。我已经实现了touchesbegan、touchesmoved和touchesended，但是我不知道如何让touchesmoved影响多张图片。

我一直在网上搜索，但没能找到这方面的任何指南。如果您能为我指出正确的方向，或提供一些基本建议，将不胜感激。

以下是示例图片：

编辑：以下是可能的图像示例：

What it should look like.

我希望能够通过同一个按键以相同的方式影响其他字母，改变它们的图片。这些图片是临时图片。

    override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
    print("touches began:\(touches)")
}

override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
            self.image = UIImage(named: "slot")!
        print("touches moved:\(touches)")
    }

override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
        self.image = UIImage(named: "tile")!
        print("touches ended")
    }

Answer 1

如果我没理解错的话，应该是这样的：

class ChangableView: UIView {
    private var touchedImageView: UIImageView? {
        didSet {
            if oldValue == touchedImageView { return }
            if let oldValue = oldValue {
                oldValue.image = UIImage(named: "tile")!
            }
            if let newValue = touchedImageView {
                newValue.image = UIImage(named: "slot")!
            }  
        }
    }

    override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
        guard let touch = touches.first else { return }
        updateTouchedImageViewWithTouch(touch, event: event)
    }

    override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
        guard let touch = touches.first else { return }
        updateTouchedImageViewWithTouch(touch, event: event)
    }

    override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
        touchedImageView = nil
    }
}

private extension ChangableView {
    func updateTouchedImageViewWithTouch(touch: UITouch, event: UIEvent?) {
        let touchPoint = touch.locationInView(self)
        let touchedView = self.hitTest(touchPoint, withEvent: event)
        touchedImageView = touchedView as? UIImageView
    }
}

此外，您的 UIViewController 应具有 ChangableView 的子类视图，并且不要忘记将所有 UIImageView 的 userInteractionEnabled 属性设置为 YES。

Touchesmoved - 单次拖动更新多个元素

Touchesmoved - updating multiple elements on single drag

touchesbegan

swift

touchesended