.h

#import 
     
      @interface YYWViewController : UIViewController
      
        @property (retain, nonatomic) IBOutlet UIPickerView *pickerView;@property(retain,nonatomic)IBOutlet UILabel *selectLabel;@property (strong, nonatomic) NSArray *pickerData;@end
      
     

.m

#import "YYWViewController.h"@interface YYWViewController ()@end@implementation YYWViewController@synthesize pickerView;@synthesize selectLabel;-(void) addPickerView {    NSArray *array = [[NSArray alloc] initWithObjects:@"",@"Luke", @"Leia",                      @"Han", @"Chewbacca", @"Artoo", @"Threepio", @"Lando", nil];    _pickerData = array;    if (pickerView == nil) {        pickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0, 240, 320, 460)];        pickerView.delegate = self;        pickerView.dataSource =self;        pickerView.showsSelectionIndicator = YES;        [self.view addSubview:pickerView];        [pickerView release];    }    }  -(void) addLabel {    if (selectLabel == nil) {        selectLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 100, 320, 40)];        selectLabel.text = @"";        selectLabel.font = [UIFont systemFontOfSize:12];        selectLabel.textAlignment = UITextAlignmentCenter;        selectLabel.backgroundColor = [UIColor grayColor];        [self.view addSubview:selectLabel];        [selectLabel release];            }    }// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.- (void)viewDidLoad {    [super viewDidLoad];    [self addPickerView];    [self addLabel];    }#pragma mark pickerView delegate//返回pickerview的组件数- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView {    return 1;}//返回每个组件上的行数- (NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component {        return [_pickerData count];}//设置每行显示的内容- (NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {     return [_pickerData objectAtIndex:row];    }//当你选中pickerview的某行时会调用该函数。- (void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {    NSLog(@"You select row %d",row);        selectLabel.text = [NSString stringWithFormat:@"you select %@",[_pickerData  objectAtIndex:row]];}//设置指定组件上每行的宽度/* -(void)pickerView:(UIPickerView *)thePickerView widthForComponet:component {  }  */- (void)didReceiveMemoryWarning {    // Releases the view if it doesn't have a superview.    [super didReceiveMemoryWarning];        // Release any cached data, images, etc that aren't in use.}- (void)dealloc {        [pickerView release];    [super dealloc];}@end