ios - 带图像的按钮，点击按钮时图像消失 iOS 10

Question

@IBAction func btnPrimaryAction(_ sender: Any) {
        btnPrimary.setImage(UIImage(named : "checkbox_on.png") , for: UIControlState.normal)
        btnSecondary.setImage(UIImage(named : "checkbox_off.png"), for: UIControlState.normal)
        btnNewAdd.setImage(UIImage(named : "checkbox_off.png") , for: UIControlState.normal)
        payType = 1
    }

我使用此代码在单击按钮时更改按钮图像。但在 iOS 10 中单击按钮时按钮图像消失。

请帮我解决这个问题 谢谢提前

Answer 1

我认为这是使用 UIButton 的有效方法状态。 UIButton有多个状态，如 UIControlState.normal,UIControlState.selected,UIControlState.highlighted ETC.. 您可以使用 UIButton 的 UIControlState 轻松解决您的问题。 首先，您需要像这样将图像设置为按钮。 在 viewDidLoad方法。

// if you have add the "checkbox_off.png and checkbox_on.png" in Images.xcassets then get the image you need to write as below
//UIImage(named : "checkbox_off") no need to add extention like ".png"

btnPrimary.setImage(UIImage(named : "checkbox_off.png") , for: UIControlState.normal)
btnSecondary.setImage(UIImage(named : "checkbox_off.png"), for: UIControlState.normal)
btnNewAdd.setImage(UIImage(named : "checkbox_off.png") , for: UIControlState.normal)

// Selected    
btnPrimary.setImage(UIImage(named : "checkbox_on.png") , for: UIControlState.selected)
btnSecondary.setImage(UIImage(named : "checkbox_on.png"), for: UIControlState.selected)
btnNewAdd.setImage(UIImage(named : "checkbox_on.png") , for: UIControlState.selected)

现在在您的函数中只需更改按钮状态

@IBAction func btnPrimaryAction(_ sender: Any) {
    btnPrimary.selected = true
    btnSecondary.selected = false
    btnNewAdd.selected = false
    payType = 1
}