Is there any way to remove the “year” of the date picker?

Question

我在一个视图中有一个日期选择器，但我只希望它显示日期和月份，而不是年份，是否有任何方法可以把这一年带出去？

Answer 1

As others have pointed out: You are left alone, to create your own picker, but actually this isn't difficult. A quick prototype, note that I use the first componet for days, second for years, this should be made acording to locale in a real world app:

-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
    return 2;
}

-(NSInteger)pickerView:pickerView numberOfRowsInComponent:(NSInteger)component
{
    NSUInteger number = 0;
    if (component == 1) {
        number = 12;
    } else {

        NSDateComponents *comps = [[NSCalendar currentCalendar] components:NSDayCalendarUnit | NSMonthCalendarUnit | NSYearCalendarUnit fromDate:[NSDate date]];

        NSUInteger month = [pickerView selectedRowInComponent:1]+1 ;
        NSUInteger actualYear = [comps year];

        NSDateComponents *selectMothComps = [[NSDateComponents alloc] init];
        selectMothComps.year = actualYear;
        selectMothComps.month = month;
        selectMothComps.day = 1;

        NSDateComponents *nextMothComps = [[NSDateComponents alloc] init];
        nextMothComps.year = actualYear;
        nextMothComps.month = month+1;
        nextMothComps.day = 1;

        NSDate *thisMonthDate = [[NSCalendar currentCalendar] dateFromComponents:selectMothComps];
        NSDate *nextMonthDate = [[NSCalendar currentCalendar] dateFromComponents:nextMothComps];

        NSDateComponents *differnce = [[NSCalendar currentCalendar]  components:NSDayCalendarUnit
                                                   fromDate:thisMonthDate
                                                     toDate:nextMonthDate
                                                    options:0];

        number = [differnce day];

    }

    return number;
}

-(void)pickerView:pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
    if (component == 1) {
        [pickerView reloadComponent:0];
    }
}

-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    return [NSString stringWithFormat:@"%d", row+1];
}

you'll find an example code at GitHub

---

The version you'll find on GitHub knows about the month's names of the most preferred language

Answer 2

Swift 3.0 version:

@IBOutlet weak var pickerCell: UIPickerView!
var months: Array<String> = Calendar.current.monthSymbols

func config() {
    pickerCell.delegate = self
    pickerCell.dataSource = self
}

func numberOfComponents(in pickerView: UIPickerView) -> Int {
    return 2
}

func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
   var number = 0
    if component == 1 {
        return 12
    } else if pickerView.numberOfComponents > 1 {
        let comps = Calendar.current.dateComponents([.day,.month, .year], from: Date())

        let month: Int = pickerView.selectedRow(inComponent: 1)+1
        let year: Int = comps.year!
        var selectMothComps = DateComponents()
        selectMothComps.year = year
        selectMothComps.month = month
        selectMothComps.day = 1

        var nextMothComps = DateComponents()
        nextMothComps.year = year
        nextMothComps.month = month+1
        nextMothComps.day = 1

        let thisMonthDate = Calendar.current.date(from: selectMothComps)
        let nextMonthDate = Calendar.current.date(from: nextMothComps)

        var difference = Calendar.current.dateComponents([.day], from: thisMonthDate!, to: nextMonthDate!)
        number = difference.day!
    }
    return number
}

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    if component == 1 {
        pickerView.reloadComponent(0)
    }
}

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    if component == 0{
        return  String(format: "%d", row+1)
    } else {
        return months[row]
    }
}
//centers the views. width > than width of smallest component
func pickerView(_ pickerView: UIPickerView, widthForComponent component: Int) -> CGFloat {
    if component == 0 {
        return 45
    }
    return 140
}

Answer 3

As far as I know, UIDatePicker cannot do this. You may use UIPickerView to do so.

Answer 4

To expand upon Oscar's answer, you will indeed have to use UIPickerView.

However that doesn't mean you code 365 days, you only need:

• A component (wheel) compromised of 12 items (months)
• A component compromised of 31 items (days)

When an item is selected you will receive its index to your delegate object. In here you simply need to work out the what item is that index.

For the month this could be achieved using a key/value style mechanism; or simply by an array whose values match that of the component/wheel. Rememering that you need a data source for the wheel anyway, you can simply look it up in that data source; most likely an array.

As for the day, you will get the index of the item. As your items (days) will begin at 1, you can simply take 1 away from the index value to find the actual day the user selected. (taking 1 away to compensate for array indexing)

selectedRowInComponent is the method that you should look at for a better understanding!

However, in future when you fear you will have to create a large amount of the same object, I suggest you look at the Factory Pattern, and have some form of iteration to call your Factory method. This isn't directly related to your question but it's certainly related to your comment above!

Hope this helps!

Answer 5

我在GitHub上找到了这个项目： PMEDatePicker