DatePicker 之類

//DatePicker

- (IBAction)buttonPressed {
NSDate *selected = [datePicker date];
NSString *message = [[NSString alloc] initWithFormat:

@"The date and time you selected is: %@", selected];UIAlertView *alert = [[UIAlertView alloc]

initWithTitle:@"Date and Time Selected"message:message

delegate:nilcancelButtonTitle:@"Yes, I did."otherButtonTitles:nil];

[alert show];} 

//single component

@interface BIDSingleComponentPickerViewController : UIViewController

<UIPickerViewDelegate, UIPickerViewDataSource>

@property (strong, nonatomic) IBOutlet UIPickerView *singlePicker;@property (strong, nonatomic) NSArray *pickerData;
- (IBAction)buttonPressed;

@end   //先聲明協議和outlet

//picker view 的delegate和sources都要連到file's owner

- (IBAction)buttonPressed {
NSInteger row = [singlePicker selectedRowInComponent:0];NSString *selected = [pickerData objectAtIndex:row];NSString *title = [[NSString alloc] initWithFormat:

@"You selected %@!", selected];

UIAlertView *alert =

[alert show];}    //顯示數據

- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional
NSArray *array = [[NSArray alloc] initWithObjects:@"Luke", @"Leia",

@"Han", @"Chewbacca", @"Artoo", @"Threepio", @"Lando", nil];self.pickerData = array;

}  //聲明數據

#pragma mark -
#pragma mark Picker Data Source Methods

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {return 1;

}

- (NSInteger)pickerView:(UIPickerView *)pickerViewnumberOfRowsInComponent:(NSInteger)component {

return [pickerData count];}

#pragma mark Picker Delegate Methods
- (NSString *)pickerView:(UIPickerView *)pickerView

titleForRow:(NSInteger)row

forComponent:(NSInteger)component {return [pickerData objectAtIndex:row];

 }  //覆寫 協議的方法

//doublePicker

#pragma mark -
#pragma mark Picker Data Source Methods
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {

return 2;}

- (NSInteger)pickerView:(UIPickerView *)pickerViewnumberOfRowsInComponent:(NSInteger)component {

if (component == kBreadComponent)return [self.breadTypes count];

return [self.fillingTypes count];}

#pragma mark Picker Delegate Methods
- (NSString *)pickerView:(UIPickerView *)pickerView

titleForRow:(NSInteger)rowforComponent:(NSInteger)component {

if (component == kBreadComponent)
return [self.breadTypes objectAtIndex:row];

return [self.fillingTypes objectAtIndex:row];}

@end

//dependentPicker

- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.

NSBundle *bundle = [NSBundle mainBundle];
NSURL *plistURL = [bundle URLForResource:@"statedictionary"

withExtension:@"plist"];NSDictionary *dictionary = [NSDictionary

dictionaryWithContentsOfURL:plistURL];

self.stateZips = dictionary;

NSArray *components = [self.stateZips allKeys];
NSArray *sorted = [components sortedArrayUsingSelector:

@selector(compare:)];self.states = sorted;

delegate:nilcancelButtonTitle:@"OK"otherButtonTitles:nil];

NSString *selectedState = [self.states objectAtIndex:0];NSArray *array = [stateZips objectForKey:selectedState];self.zips = array;

} //處理數據

#pragma mark -
#pragma mark Picker Data Source Methods

• -  (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {

  return 2;}

• -  (NSInteger)pickerView:(UIPickerView *)pickerViewnumberOfRowsInComponent:(NSInteger)component {

  if (component == kStateComponent)return [self.states count];

  return [self.zips count];}

  #pragma mark Picker Delegate Methods

  • -  (NSString *)pickerView:(UIPickerView *)pickerView

    titleForRow:(NSInteger)rowforComponent:(NSInteger)component {

    if (component == kStateComponent)
    return [self.states objectAtIndex:row];

    return [self.zips objectAtIndex:row];}

  • -  (void)pickerView:(UIPickerView *)pickerViewdidSelectRow:(NSInteger)row

    inComponent:(NSInteger)component {if (component == kStateComponent) {

    NSString *selectedState = [self.states objectAtIndex:row];NSArray *array = [stateZips objectForKey:selectedState];self.zips = array;
    [picker selectRow:0 inComponent:kZipComponent animated:YES];[picker reloadComponent:kZipComponent];

    }}