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
你可以通过这种方式添加UIButton,UIlable和UITextfield。
UIButton代码
// var button = UIButton.buttonWithType(UIButtonType.System) as UIButton
let button = UIButton(type: .System) // let preferred over var here
button.frame = CGRectMake(100, 100, 100, 50)
button.backgroundColor = UIColor.greenColor()
button.setTitle("Button", forState: UIControlState.Normal)
button.addTarget(self, action: "Action:", forControlEvents: UIControlEvents.TouchUpInside)
self.view.addSubview(button)
UILabel代码
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)
UITextField 代码
var txtField: UITextField = UITextField()
txtField.frame = CGRectMake(50, 70, 200, 30)
txtField.backgroundColor = UIColor.grayColor()
self.view.addSubview(txtField)
希望这对你有帮助。
其他回答
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")
}
}
var sampleButton:UIButton?
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewDidAppear(animated: Bool) {
sampleButton = UIButton(type: .RoundedRect)
//sampleButton.frame = CGRect(x:50, y:500, width:70, height:50)
sampleButton!.setTitle("Sample \n UI Button", forState: .Normal)
sampleButton!.titleLabel?.lineBreakMode = .ByWordWrapping
sampleButton!.titleLabel?.textAlignment = .Center
sampleButton!.setTitleColor(UIColor.whiteColor(), forState: .Normal)
sampleButton!.layer.cornerRadius = 6
sampleButton!.backgroundColor = UIColor.redColor().colorWithAlphaComponent(0.6)
sampleButton?.tintColor = UIColor.brownColor()
//Add padding around text
sampleButton!.titleEdgeInsets = UIEdgeInsetsMake(-10,-10,-10,-10)
sampleButton!.contentEdgeInsets = UIEdgeInsetsMake(5,5,5,5)
//Action set up
sampleButton!.addTarget(self, action: "sampleButtonClicked", forControlEvents: .TouchUpInside)
self.view.addSubview(sampleButton!)
//Button Constraints:
sampleButton!.translatesAutoresizingMaskIntoConstraints = false
//To anchor above the tab bar on the bottom of the screen:
let bottomButtonConstraint = sampleButton!.bottomAnchor.constraintEqualToAnchor(bottomLayoutGuide.topAnchor, constant: -20)
//edge of the screen in InterfaceBuilder:
let margins = view.layoutMarginsGuide
let leadingButtonConstraint = sampleButton!.leadingAnchor.constraintEqualToAnchor(margins.leadingAnchor)
bottomButtonConstraint.active = true
leadingButtonConstraint.active = true
}
func sampleButtonClicked(){
print("sample Button Clicked")
}
如何使用Swift 3.0来做到这一点。
func createButton() {
let button = UIButton(type: .system)
button.frame = CGRect(x: 100.0, y: 100.0, width: 100.0, height: 100.0)
button.setTitle(NSLocalizedString("Button", comment: "Button"), for: .normal)
button.backgroundColor = .green
button.addTarget(self, action: #selector(buttonAction(sender:)), for: .touchUpInside)
view.addSubview(button)
}
@objc func buttonAction(sender: UIButton) {
print("Button pushed")
}
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。
我通常会设置uibutton的扩展。斯威夫特5。
let button: UIButton = UIButton()
override func viewDidLoad() {
super.viewDidLoad()
button.setup(title: "OK", x: 100, y: 430, width: 220, height: 80, color: .yellow)
buttonD.setTitleColor(.black, for: .normal)
}
extension UIButton {
func setup(title: String, x: CGFloat, y: CGFloat, width: CGFloat, height: CGFloat, color: UIColor){
frame = CGRect(x: x, y: y, width: width, height: height)
backgroundColor = color
setTitle(title , for: .normal)
}
}
推荐文章
- 如何删除默认的导航栏空间在SwiftUI导航视图
- 如何在iOS中使用Swift编程segue
- Swift -整数转换为小时/分钟/秒
- 如何舍入一个双到最近的Int在迅速?
- 扁平化数组的数组在Swift
- Swift:声明一个空字典
- 在成功提交我的应用程序后,“太多符号文件”
- 从数组中随机选择一个元素
- 首先添加一个UIView,甚至是导航栏
- 我如何改变UIButton标题颜色?
- 在Swift中如何调用GCD主线程上的参数方法?
- NSLayoutConstraints是可动画的吗?
- iOS -构建失败,CocoaPods无法找到头文件
- CFNetwork SSLHandshake iOS 9失败
- swift语言中的结构与类