意圖
PickerView上顯示指定時(shí)間區(qū)間(yyyy/MM)之間的時(shí)間
探索之道
- 系統(tǒng)自帶的控件
UIDatePicker逸寓，無法只顯示年至耻、月 - gitbub上有第三方栋齿，自己實(shí)現(xiàn)的DatePicker疾瓮，需要額外引入許多文件撮弧，計(jì)算復(fù)雜淀歇，而且想修改的話易核，需要讀懂大量源碼
- 系統(tǒng)自帶的控件
UIPickerView，可以顯示數(shù)據(jù)浪默，但是需要組裝數(shù)據(jù)
綜上所述牡直，這里選擇使用PickerView，組裝數(shù)據(jù)源纳决，以實(shí)現(xiàn)需求井氢。
思路
- 目的：計(jì)算兩個(gè)日期之間的年月
- 方法：
- 從大到小，讓月份遞減岳链，直到年月等于最小值即可
- 獲取所有的年月后花竞，根據(jù)年份組合，得到每一年以及這一年中所有的月份
- 將組裝后的數(shù)據(jù)填充在PickerView上
數(shù)據(jù)加工
創(chuàng)建模型
- 為了處理數(shù)據(jù)方便掸哑，這里使用了模型约急，當(dāng)然，用字典也是可以的苗分，只要你想厌蔽。
class YearModel: NSObject {
var name: String?
var months: [String]?
override var description: String {
return "name: \(name ?? "") months: \(months ?? [])"
}
}
※ 開始組裝數(shù)據(jù)
var minDateStr = "2016/09"
var maxDateStr = "2017/04"
var fmtStr = "yyyy/MM"
private func setupDatasource() -> [YearModel] {
print("=================== 數(shù)據(jù)處理開始 =================")
var currentMonth = ""
let fmt = NSDateFormatter()
fmt.locale = NSLocale.currentLocale()
fmt.dateFormat = fmtStr
var date = fmt.dateFromString(maxDateStr ?? "") ?? NSDate()
var yearMonthList: [String] = []
var i = 0
// 循環(huán)，月份遞減摔癣，直到年月等于最小值即可
// 注意：循環(huán)退出條件奴饮，避免死循環(huán)！
repeat {
let calender = NSCalendar(calendarIdentifier: NSCalendarIdentifierGregorian)
let adcomps = NSDateComponents()
adcomps.year = 0
// 因?yàn)檫@里需要包含最大月份择浊，所以需要這個(gè)判斷
adcomps.month = i == 0 ? 0 : -1
i += 1
date = calender?.dateByAddingComponents(adcomps, toDate: date, options: NSCalendarOptions(rawValue: UInt(0))) ?? NSDate()
currentMonth = fmt.stringFromDate(date)
print("\(date) | \(currentMonth)")
if i > 100 {
print("可能是死循環(huán)戴卜，手動(dòng)跳出循環(huán)")
break
}
yearMonthList.append(currentMonth)
} while currentMonth != minDateStr
// 存儲(chǔ)處理后的數(shù)據(jù)集
var resultList: [YearModel] = []
// 存儲(chǔ)年月數(shù)據(jù)對(duì)象(year-months)
var yearModel = YearModel()
// 存儲(chǔ)該 year 中包含的所有 month
var monthTmpList: [String] = []
for obj in yearMonthList {
let tmpList = obj.split("/")
let year = tmpList.first!
let month = tmpList.last!
if yearModel.name == year {
// 當(dāng)前 year 在 resultList 中已存儲(chǔ)，局部變量不需要初始化
} else {
// 當(dāng)前 year 在 resultList 中未存儲(chǔ)琢岩，是新的年份投剥，所以需要對(duì)部分變量初始化！
monthTmpList = []
yearModel = YearModel()
yearModel.name = year
}
monthTmpList.append(month)
yearModel.months = monthTmpList
print("\(yearModel)")
var i = 0
for model in resultList {
// 去除月份不“完整”的數(shù)據(jù)担孔，最后只會(huì)保留該 year 中江锨，month 最完整的那條記錄
if let currentObj = model.months where currentObj.count > 0 {
if model.name == yearModel.name {
resultList.removeAtIndex(i)
}
}
i += 1
}
resultList.append(yearModel)
}
print("\(resultList)")
print("=================== 數(shù)據(jù)處理完畢 =================")
return resultList
}
數(shù)據(jù)處理過程，log截圖如下：
年月PickerView-Log輸出.png
數(shù)據(jù)展示
var index = 0
// MARK: - <UIPickerViewDelegate>
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 2
}
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
if component == 0 {
// 如果想“無限”滾動(dòng)糕篇，就返回一個(gè)比較大的值啄育，然后取值的時(shí)候，模上它本來的數(shù)量即可
// e.g. return dataSource.count * 1000
return dataSource.count
} else {
if dataSource.count == 0 { return 0 }
let yearModel = dataSource[index]
return yearModel.months?.count ?? 0
}
}
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
if component == 0 {
let yearModel = dataSource[row]
return yearModel.name
} else {
let yearModel = dataSource[index]
return yearModel.months?[row]
}
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
if component == 0 {
index = pickerView.selectedRowInComponent(0)
pickerView.reloadComponent(1)
}
if dataSource.count == 0 { return }
let yearModel = dataSource[index]
let monthIndex = pickerView.selectedRowInComponent(1)
let month = yearModel.months?[monthIndex]
let dateStr = "\(yearModel.name ?? "")/\(month ?? "")"
txfDate.text = dateStr
}
效果圖
年月PickerView效果圖.png
