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
你可以这样创建,也可以这样添加动作....
import UIKit
let myButton = UIButton(frame: CGRect(x: 0, y: 0, width: 50, height: 50))
init(nibName nibNameOrNil: String!, bundle nibBundleOrNil: NSBundle!)
{ super.init(nibName: nibName, bundle: nibBundle)
myButton.targetForAction("tappedButton:", withSender: self)
}
func tappedButton(sender: UIButton!)
{
println("tapped button")
}
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")
}
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)
}
}
在Swift 4.2中编写下面的示例代码,用于以编程方式添加按钮。
override func viewDidLoad() {
super.viewDidLoad()
let myButton = UIButton(frame: CGRect(x: 100, y: 100, width: 100, height: 50))
myButton.backgroundColor = .green
myButton.setTitle("Hello UIButton", for: .normal)
myButton.addTarget(self, action: #selector(myButtonAction), for: .touchUpInside)
self.view.addSubview(myButton)
}
@objc func myButtonAction(sender: UIButton!) {
print("My Button tapped")
}
API没有改变——只有语法改变了。你可以创建一个UIButton并像这样添加它:
var button = UIButton(frame: CGRectMake(0, 0, 50, 50))
self.view.addSubview(button) // assuming you're in a view controller
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