显示DatePicker的当前日期
NSDate*selected= [datepicker date];
NSString*message = [[NSStringalloc]initWithFormat:@“选择的日期和时间是:%@”, selected];
UIAlertView*alert = [[UIAlertViewalloc] initWithTitle:@"日期和时间" message:message delegate: nil cancelButtonTitle:@"关闭" otherButtonTitles:nil];
[alert show];
设置DatePicker为当前时间
NSDate *now = [[NSDatealloc]init];
[datepickersetDate:nowanimated:YES];
单列PickerView的核心事件方法
// 返回列表数
- (NSInteger)pickerView:(UIPickerView *)pickerView
numberOfRowsInComponent:(NSInteger)component {
return [pickerData count];
}
// 返回每个列表项的文本
- (NSString *)pickerView:(UIPickerView *)pickerView
titleForRow:(NSInteger)row
forComponent:(NSInteger)component {
return [pickerDataobjectAtIndex:row];
}
双列PickerView的核心事件(1)
// 返回两列
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
return 2;
}
// 返回每一列的列表项数
- (NSInteger)pickerView:(UIPickerView *)pickerView
numberOfRowsInComponent:(NSInteger)component {
if (component == LEFT)
return [self.leftArray count];
return [self.rightArray count];
}
双列PickerView的核心事件(2)
- (NSString *)pickerView:(UIPickerView *)pickerView
titleForRow:(NSInteger)row
forComponent:(NSInteger)component {
if (component == LEFT)
return [self.leftArrayobjectAtIndex:row];
return [self.rightArrayobjectAtIndex:row];
}
获取当前双列的列表项
NSIntegerleftRow = [pickerviewselectedRowInComponent:
LEFT];
NSIntegerrightRow = [pickerviewselectedRowInComponent:
RIGHT];
NSString *left = [leftArrayobjectAtIndex:leftRow];
NSString *right = [rightArrayobjectAtIndex:rightRow];
// 获取列表项(两列)
NSString *message = [[NSStringalloc] initWithFormat:
@"Left: %@ Right:%@", left, right];
获取当前双列的列表项
NSIntegerleftRow = [pickerviewselectedRowInComponent:
LEFT];
NSIntegerrightRow = [pickerviewselectedRowInComponent:
RIGHT];
NSString *left = [leftArrayobjectAtIndex:leftRow];
NSString *right = [rightArrayobjectAtIndex:rightRow];
// 获取列表项(两列)
NSString *message = [[NSStringalloc] initWithFormat:
@"Left: %@ Right:%@", left, right];