iOS UIImageView 点击只在 View 的顶部注册

Question

我正在做一个在屏幕上绘制井字棋网格的项目。

问题是，对于“tiles”的底行，UITapGestureRecognizer 无法正常工作。对于网格的前两行，当识别器分配到的 UIImageView 的任何部分被点击时，将调用适当的函数。但是，对于底行，它仅在 UIImageView 的最顶部被点击时才有效。

代码如下:

func drawTiles() {
    for view in subviews {
        if (view as? UIImageView != nil) {
            view.removeFromSuperview()
        }
    }

    // Upper Left Tile [0][0]
    var view = UIImageView(image: battleGround.tiles[0][0].image)
    view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(upperLeftTapped)))
    view.isUserInteractionEnabled = true
    view.frame = CGRect(x: frame.minX, y: frame.minY, width: frame.width / 3, height: frame.height / 3)
    addSubview(view)

    // Upper Middle Tile [0][1]
    view = UIImageView(image: battleGround.tiles[0][1].image)
    view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(upperCenterTapped)))
    view.isUserInteractionEnabled = true
    view.frame = CGRect(x: frame.minX + frame.width / 3, y: frame.minY, width: frame.width / 3, height: frame.height / 3)
    addSubview(view)

    // Upper Right Tile [0][2]
    view = UIImageView(image: battleGround.tiles[0][2].image)
    view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(upperRightTapped)))
    view.isUserInteractionEnabled = true
    view.frame = CGRect(x: frame.minX + ((frame.width / 3) * 2), y: frame.minY, width: frame.width / 3, height: frame.height / 3)
    addSubview(view)



    // Middle Left Tile [1][0]
    view = UIImageView(image: battleGround.tiles[1][0].image)
    view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(middleLeftTapped)))
    view.isUserInteractionEnabled = true
    view.frame = CGRect(x: frame.minX, y: frame.minY + ((frame.height / 3)), width: frame.width / 3, height: frame.height / 3)
    addSubview(view)

    // Middle Center Tile [1][1]
    view = UIImageView(image: battleGround.tiles[1][1].image)
    view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(middleCenterTapped)))
    view.isUserInteractionEnabled = true
    view.frame = CGRect(x: frame.minX + ((frame.width / 3)), y: frame.minY + ((frame.height / 3)), width: frame.width / 3, height: frame.height / 3)
    addSubview(view)

    // Middle Center Tile [1][2]
    view = UIImageView(image: battleGround.tiles[1][2].image)
    view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(middleRightTapped)))
    view.isUserInteractionEnabled = true
    view.frame = CGRect(x: frame.minX + ((frame.width / 3) * 2), y: frame.minY + ((frame.height / 3)), width: frame.width / 3, height: frame.height / 3)
    addSubview(view)

    // FIXME: Only clicking the top of the next 3 views works

    // Lower Left Tile [2][0]
    view = UIImageView(image: battleGround.tiles[2][0].image)
    view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(lowerLeftTapped)))
    view.isUserInteractionEnabled = true
    view.frame = CGRect(x: frame.minX, y: frame.minY + ((frame.height / 3) * 2), width: frame.width / 3, height: frame.height / 3)
    addSubview(view)

    // Lower Center Tile [2][1]
    view = UIImageView(image: battleGround.tiles[2][1].image)
    view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(lowerCenterTapped)))
    view.isUserInteractionEnabled = true
    view.frame = CGRect(x: frame.minX + ((frame.width / 3)), y: frame.minY + ((frame.height / 3) * 2), width: frame.width / 3, height: frame.height / 3)
    addSubview(view)

    // Lower Right Tile [2][2]
    view = UIImageView(image: battleGround.tiles[2][2].image)
    view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(lowerRightTapped)))
    view.isUserInteractionEnabled = true
    view.frame = CGRect(x: frame.minX + ((frame.width / 3) * 2), y: frame.minY + ((frame.height / 3) * 2), width: frame.width / 3, height:frame.height / 3)
    addSubview(view)
}

func upperLeftTapped() {
    tapped(row: 0, column: 0)
}

func upperCenterTapped(){
    tapped(row: 0, column: 1)
}

func upperRightTapped() {
    tapped(row: 0, column: 2)
}

func middleLeftTapped() {
    tapped(row: 1, column: 0)
}

func middleCenterTapped() {
    tapped(row: 1, column: 1)
}
func middleRightTapped() {
    tapped(row: 1, column: 2)
}

func lowerLeftTapped() {
    tapped(row: 2, column: 0)
}

func lowerCenterTapped() {
    tapped(row: 2, column: 1)
}

func lowerRightTapped() {
    tapped(row: 2, column: 2)
}

func tapped(row: Int, column: Int) {
    if (battleGround.tiles[row][column] == .empty) {
        battleGround.tiles[row][column] = currentPlayer

        drawTiles()
    }
}

这里是要注意的代码(什么绘制了网格的下行)

// Lower Left Tile [2][0]
view = UIImageView(image: battleGround.tiles[2][0].image)
view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(lowerLeftTapped)))
view.isUserInteractionEnabled = true
view.frame = CGRect(x: frame.minX, y: frame.minY + ((frame.height / 3) * 2), width: frame.width / 3, height: frame.height / 3)
addSubview(view)

// Lower Center Tile [2][1]
view = UIImageView(image: battleGround.tiles[2][1].image)
view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(lowerCenterTapped)))
view.isUserInteractionEnabled = true
view.frame = CGRect(x: frame.minX + ((frame.width / 3)), y: frame.minY + ((frame.height / 3) * 2), width: frame.width / 3, height: frame.height / 3)
addSubview(view)

// Lower Right Tile [2][2]
view = UIImageView(image: battleGround.tiles[2][2].image)
view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(lowerRightTapped)))
view.isUserInteractionEnabled = true
view.frame = CGRect(x: frame.minX + ((frame.width / 3) * 2), y: frame.minY + ((frame.height / 3) * 2), width: frame.width / 3, height:frame.height / 3)
addSubview(view)

编辑:以下是应用程序运行时的一些屏幕截图，以便更好地了解问题所在。

此屏幕截图显示了空网格的样子。

此屏幕截图显示了我单击网格的顶部中间和中间左侧的图 block 后的网格。如您所见，图像已正确添加。

但是，如果我点击网格的底行，则没有任何反应。看看这个 GIF:

我多次点击底部中间，但没有任何反应。然而，在中心敲击工作正常。

这是有趣的部分:点击同一个底部中间图 block 的顶部会导致图像出现。看一看:

如有任何帮助，我们将不胜感激!

Answer 1

使用 Debug -> View Debugging -> Capture View Hierarchy，并检查您插入所有这些图 block 的 View 是否实际延伸到您假设的范围。

一个简单的测试也是使用 self.clipsToBounds = YES; 如果您看不到所有图 block ，则说明您的包含 View 不够大，这意味着手势无法正确转发到手势识别器。