Swift3 從入門到精通Day12：UIAlertController
時間：5/21（日）
內容：
- 89. 警告控制器 UIAlertController
- 90. 幫警告控制器加上按鈕9:51
- 91. 顯示圖片 UIImageView7:41
- 92. 用程式碼換圖3:10
- 93. 按鈕 UIButton6:19
- 94. 用程式碼產生按鈕10:58
- 95. 選單 PickerView8:05
- 96. 設定選單的選項9:19
- 97. 複習與總結 UIPickerView3:05
- 98. 協定 Protocol8:57
- 99. 解釋 UIPickerViewDelegate 的原理6:34
- 100. 解釋 UIPickerViewDataSource 的原理3:46
- 101. 協定導向程式設計 Protocol Oriented Programming9:19
- 89. 警告控制器 UIAlertController
@IBAction func showAlert(_ sender: UIButton) {
let myAlert = UIAlertController(title: “Hello”, message: “How are you”, preferredStyle: .alert)
present(myAlert, animated: true, completion: nil)
}
- 90. 幫警告控制器加上按鈕9:51
import UIKit
class ViewController: UIViewController {
@IBAction func showAlert(_ sender: UIButton) {
let myAlert = UIAlertController(title: “Hello”, message: “How are you”, preferredStyle: .actionSheet)
let OKAction = UIAlertAction(title: “Ok”, style: .default) {
(action:UIAlertAction) in
self.dismiss(animated: true, completion: nil)
}
myAlert.addAction(OKAction)
let HelloAction = UIAlertAction(title: “Say Hello”, style: .cancel) {
(action:UIAlertAction) in
print(“Hello”)
self.dismiss(animated: true, completion: nil)
}
myAlert.addAction(HelloAction)
let cancelAction = UIAlertAction(title: “cancel”, style: .destructive) {
(action:UIAlertAction) in
print(“Hello”)
self.dismiss(animated: true, completion: nil)
}
myAlert.addAction(cancelAction)
present(myAlert, animated: true, completion: nil)
}
頁面呈現方式
preferredStyle: .actionSheet
preferredStyle: .alert
字型（影響顏色、粗體）
style: .cancel
style: .destructive
style: .default
- 91. 顯示圖片 UIImageView7:41
Scale To Fill 失真放大
Aspect TO Fit 任一側到底
Aspect TO Fill 兩側到底不失真
- 92. 用程式碼換圖3:10
myPet.image = UIImage(name: “MyCat”)
就可以把狗的照片換成貓了（但也要先匯入貓的圖片）
- 93. 按鈕 UIButton6:19
button旁邊用image找到選PlayButton
然後
調整成highlight按下按鈕之後顯示PlayButtonPressed圖示
- 94. 用程式碼產生按鈕10:58
95. 選單 PickerView8:05
import UIKit
class ViewController: UIViewController,UIPickerViewDataSource{
//how many component in pickerview
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 2
}
//how many row in component
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
if component == 0{
return 2
}else{
return 4
}
}
第一個return 2＝兩排字
第二個return 2＝第一排兩個選項
return 4第二排四個選項
- 96. 設定選單的選項9:19
delegate也是連到view controler
import UIKit
class ViewController: UIViewController,UIPickerViewDataSource,UIPickerViewDelegate{
let numberArray = [“1”,”2",”3",”4",”5",”6",”7",”8"]
let fruitArray = [“apple”,”banana”,”moango”,”watermelon”]
//how many component in pickerview
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 2
}
//how many row in component
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
if component == 0{
return numberArray.count
}else{
return fruitArray.count
}
}
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
if component == 0 {
return numberArray[row]
}else{
return fruitArray[row]
}
}
- 97. 複習與總結 UIPickerView3:05
- 98. 協定 Protocol8:57
- 99. 解釋 UIPickerViewDelegate 的原理6:34
- 98. 協定 Protocol8:57
- 99. 解釋 UIPickerViewDelegate 的原理6:34
- 100. 解釋 UIPickerViewDataSource 的原理3:46
- 101. 協定導向程式設計 Protocol Oriented Programming9:19
心得：Protocol好難我看影片我大概每片都重複看了好幾次
有點一知半解的感覺我決定去看實體書再試一次😅
