前几天逛Github，偶然看到一个Swift的项目 —— 30DaysOfSwift,作者一共用30个小项目，来熟悉Swift语言，而我正好也学习了一段时间的Swift语言，准备仿照这样的模式，来更加深入的了解UI部分
今天做的是一个计时器项目，大概效果如下 :
作者在这个项目中，使用AutoLayout来完成自动布局，使用StoryBoard完成UI创建。
而我一直都是喜欢用纯代码布局，UI的搭建也是使用代码完成。所以我在写这个小Demo之前在我的项目里集成了SnapKit，使用类似Objective-C中常用的masonry框架来完成自动布局。
这里我还发现一个Swift中的小问题，使用cocoadPods集成第三方库，引用不到头文件的解决方法和Objective-C不一样。
这是第一个Swift小Demo，很简单，也很好的帮助熟悉UI.
import UIKit
import SnapKit
let SCREEN_WIDTH = UIScreen.mainScreen().bounds.size.width
let SCREEN_HEIGHT = UIScreen.mainScreen().bounds.size.height
let kTopViewHeight = SCREEN_HEIGHT * 0.4 //倒计时试图高度
let kButtonHeight = SCREEN_HEIGHT * 0.6 //开始暂停按钮高度
let kPauseButtonWidth = SCREEN_WIDTH * 0.4 //暂停按钮宽度
let kStartButtonWidth = SCREEN_WIDTH * 0.6 //开始按钮高度
var counter = 0.0
var timer = NSTimer()
var isPlaying = false
class ViewController: UIViewController {
//MARK: - 懒加载
//倒计时Label
private lazy var showLabel: UILabel = {
let label = UILabel(frame: CGRect.zero)
label.text = String(counter)
label.textColor = UIColor.yellowColor()
label.font = UIFont.systemFontOfSize(100)
label.textAlignment = NSTextAlignment.Center
return label
}()
//顶部背景试图
private lazy var topBackgroundView: UIView = {
let view = UIView(frame: CGRect(x: 0, y: 0, width: SCREEN_WIDTH, height: kTopViewHeight))
view.backgroundColor = UIColor.blackColor()
return view
}()
//Reset按钮
private lazy var resetButton: UIButton = {
let button = UIButton(type: (UIButtonType.Custom))
button.frame = CGRectZero
button.setTitle("Reset", forState: UIControlState.Normal)
button.setTitleColor(UIColor.whiteColor(), forState: UIControlState.Normal)
button.setTitleColor(UIColor.blackColor(), forState: UIControlState.Highlighted)
button.titleLabel?.font = UIFont.systemFontOfSize(15)
button.backgroundColor = UIColor.clearColor()
button.addTarget(self, action: "buttonDidClick:", forControlEvents: UIControlEvents.TouchUpInside)
button.tag = 101
return button
}()
//暂停按钮
private lazy var pauseButton: UIButton = {
let button = UIButton(type: (UIButtonType.Custom))
button.frame = CGRectZero
button.setImage(UIImage(named: "pause"), forState: UIControlState.Normal)
button.backgroundColor = UIColor.greenColor()
button.addTarget(self, action: "buttonDidClick:", forControlEvents: UIControlEvents.TouchUpInside)
button.tag = 102
return button
}()
//开始按钮
private lazy var startButton: UIButton = {
let button = UIButton(type: (UIButtonType.Custom))
button.frame = CGRectZero
button.setImage(UIImage(named: "play"), forState: UIControlState.Normal)
button.backgroundColor = UIColor.blueColor()
button.addTarget(self, action: "buttonDidClick:", forControlEvents: UIControlEvents.TouchUpInside)
button.tag = 103
return button
}()
//MARK: - 创建UI界面
func setupUI() {
//顶部的背景试图
self.view.addSubview(self.topBackgroundView)
// 显示倒计时的Label
self.topBackgroundView.addSubview(self.showLabel)
self.showLabel.snp_makeConstraints { make in
make.width.equalTo(SCREEN_WIDTH)
make.height.equalTo(137)
make.centerX.equalTo(self.topBackgroundView.snp_centerX)
make.centerY.equalTo(self.topBackgroundView.snp_centerY)
}
//Reset按钮
self.topBackgroundView.addSubview(self.resetButton)
self.resetButton.snp_makeConstraints { make in
make.top.equalTo(self.topBackgroundView.snp_top).offset(20)
make.right.equalTo(self.topBackgroundView.snp_right).offset(-20)
make.height.equalTo(20)
make.width.equalTo(60)
}
// 暂停按钮
self.view.addSubview(self.pauseButton)
self.pauseButton.snp_makeConstraints { make in
make.top.equalTo(self.topBackgroundView.snp_bottom).offset(0)
make.left.equalTo(self.view).offset(0)
make.height.equalTo(kButtonHeight)
make.width.equalTo(kPauseButtonWidth)
}
//开始按钮
self.view .addSubview(self.startButton)
self.startButton.snp_makeConstraints { make in
make.top.equalTo(self.topBackgroundView.snp_bottom).offset(0)
make.left.equalTo(self.pauseButton.snp_right).offset(0)
make.height.equalTo(kButtonHeight)
make.width.equalTo(kStartButtonWidth)
}
}
//MARK: - 设置状态栏
override func preferredStatusBarStyle() -> UIStatusBarStyle {
return UIStatusBarStyle.LightContent
}
//MARK: - ButtonClick
func buttonDidClick(sender: AnyObject) {
switch sender.tag {
//reset
case 101 :
timer.invalidate()
isPlaying = false
counter = 0.0
self.showLabel.text = String(counter)
self.startButton.enabled = true
self.pauseButton.enabled = false
//暂停
case 102 :
self.startButton.enabled = true
self.pauseButton.enabled = false
isPlaying = false
timer.invalidate()
//开始
case 103 :
if (isPlaying) {
return
}
self.startButton.enabled = false
self.pauseButton.enabled = true
timer = NSTimer.scheduledTimerWithTimeInterval(0.1, target: self, selector: Selector("updateTimer"), userInfo: nil, repeats: true)
isPlaying = true
default :
break
}
}
//MARK: - 计时器方法
func updateTimer() {
counter = counter + 0.1
self.showLabel.text = String(format: "%.1f", counter)
}
override func viewDidLoad() {
super.viewDidLoad()
self.view.backgroundColor = UIColor.whiteColor()
setupUI()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
