我如何以编程方式创建图形元素(如UIButton)在Swift?我试图创建和添加按钮到一个视图,但不能。
当前回答
是的,在模拟器里。有时它不会识别选择器,这似乎是一个错误。即使我面对的不是你的代码,然后我只是改变了动作名称(选择器)。它的工作原理
let buttonPuzzle:UIButton = UIButton(frame: CGRectMake(100, 400, 100, 50))
buttonPuzzle.backgroundColor = UIColor.greenColor()
buttonPuzzle.setTitle("Puzzle", forState: UIControlState.Normal)
buttonPuzzle.addTarget(self, action: "buttonAction:", forControlEvents: UIControlEvents.TouchUpInside)
buttonPuzzle.tag = 22;
self.view.addSubview(buttonPuzzle)
选择器函数在这里:
func buttonAction(sender:UIButton!)
{
var btnsendtag:UIButton = sender
if btnsendtag.tag == 22 {
//println("Button tapped tag 22")
}
}
其他回答
Swift:以编程方式创建Ui按钮
let myButton = UIButton()
myButton.titleLabel!.frame = CGRectMake(15, 54, 300, 500)
myButton.titleLabel!.text = "Button Label"
myButton.titleLabel!.textColor = UIColor.redColor()
myButton.titleLabel!.textAlignment = .Center
self.view.addSubview(myButton)
下面是一个完整的解决方案,以编程方式添加一个UIButton与targetAction。 斯威夫特2.2
override func viewDidLoad() {
super.viewDidLoad()
let button = UIButton(frame: CGRect(x: 100, y: 100, width: 100, height: 50))
button.backgroundColor = .greenColor()
button.setTitle("Test Button", forState: .Normal)
button.addTarget(self, action: #selector(buttonAction), forControlEvents: .TouchUpInside)
self.view.addSubview(button)
}
func buttonAction(sender: UIButton!) {
print("Button tapped")
}
使用NSLayoutConstraint而不是frame来正确地为每个iPhone屏幕放置按钮可能更好。
Swift 3.1的更新代码:
override func viewDidLoad() {
super.viewDidLoad()
let button = UIButton(frame: CGRect(x: 100, y: 100, width: 100, height: 50))
button.backgroundColor = .green
button.setTitle("Test Button", for: .normal)
button.addTarget(self, action: #selector(buttonAction), for: .touchUpInside)
self.view.addSubview(button)
}
func buttonAction(sender: UIButton!) {
print("Button tapped")
}
Swift 4.2的更新代码:
override func viewDidLoad() {
super.viewDidLoad()
let button = UIButton(frame: CGRect(x: 100, y: 100, width: 100, height: 50))
button.backgroundColor = .green
button.setTitle("Test Button", for: .normal)
button.addTarget(self, action: #selector(buttonAction), for: .touchUpInside)
self.view.addSubview(button)
}
@objc func buttonAction(sender: UIButton!) {
print("Button tapped")
}
如果func buttonAction声明为private或internal,上述方法仍然有效。
func viewDidLoad(){
saveActionButton = UIButton(frame: CGRect(x: self.view.frame.size.width - 60, y: 0, width: 50, height: 50))
self.saveActionButton.backgroundColor = UIColor(red: 76/255, green: 217/255, blue: 100/255, alpha: 0.7)
saveActionButton.addTarget(self, action: #selector(doneAction), for: .touchUpInside)
self.saveActionButton.setTitle("Done", for: .normal)
self.saveActionButton.layer.cornerRadius = self.saveActionButton.frame.size.width / 2
self.saveActionButton.layer.borderColor = UIColor.darkGray.cgColor
self.saveActionButton.layer.borderWidth = 1
self.saveActionButton.center.y = self.view.frame.size.height - 80
self.view.addSubview(saveActionButton)
}
func doneAction(){
print("Write your own logic")
}
在Swift 2和iOS 9.2.1中
var button: UIButton = UIButton(type: UIButtonType.Custom) as UIButton
self.button.frame = CGRectMake(130, 70, 60, 20)
self.button.setTitle("custom button", forState: UIControlState.Normal)
self.button.addTarget(self, action:"buttonActionFuncName", forControlEvents: UIControlEvents.TouchUpInside)
self.button.setTitleColor(UIColor.blackColor(), forState: .Normal)
self.button.layer.borderColor = UIColor.blackColor().CGColor
self.button.titleLabel?.font = UIFont(name: "Helvetica-Bold", size: 13)
self.view.addSubview(self.button)
Uilabel code
var label: UILabel = UILabel()
label.frame = CGRectMake(50, 50, 200, 21)
label.backgroundColor = UIColor.blackColor()
label.textColor = UIColor.whiteColor()
label.textAlignment = NSTextAlignment.Center
label.text = "test label"
self.view.addSubview(label)
推荐文章
- 更改UITextField和UITextView光标/插入符颜色
- 如何使用@Binding变量实现自定义初始化
- 'Project Name'是通过优化编译的——步进可能会表现得很奇怪;变量可能不可用
- Swift设置为Array
- 如何设置回退按钮文本在Swift
- 我如何能在Swift扩展类型化数组?
- Swift类错误:属性未在super处初始化。init调用
- 模拟器慢动作动画现在打开了吗?
- 如何为TableView创建NSIndexPath
- 滑动删除和“更多”按钮(就像iOS 7的邮件应用程序)
- 使UINavigationBar透明
- 如何改变推和弹出动画在一个基于导航的应用程序
- 删除/重置核心数据中的所有条目?
- Swift to Objective-C头未在Xcode 6中创建
- setNeedsLayout vs. setNeedsUpdateConstraints和layoutIfNeeded vs. updateConstraintsIfNeeded