iphone的PickerView使用

1. File -> New Project -> View-based Application ->  输入工程名称 PickerView

 

2. PickerViewViewController.h

    

#import <UIKit/UIKit.h>  
@interface PickerViewViewController : UIViewController<UIPickerViewDataSource, UIPickerViewDelegate>  
{  
    UIPickerView *m_pPickerView;  
    NSArray *m_data;  
}  
@property (nonatomic, retain) IBOutlet UIPickerView *m_pPickerView;  
@property (nonatomic, retain) NSArray *m_data;  
@end  

 3. PickerViewViewController.m

#import "PickerViewViewController.h"  
@implementation PickerViewViewController  
@synthesize m_pPickerView, m_data;  
/* 
// The designated initializer. Override to perform setup that is required before the view is loaded. 
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { 
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; 
    if (self) { 
        // Custom initialization 
    } 
    return self; 
} 
*/  
/* 
// Implement loadView to create a view hierarchy programmatically, without using a nib. 
- (void)loadView { 
} 
*/  
  
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.  
- (void)viewDidLoad {  
    NSArray *arr = [[NSArray alloc] initWithObjects:@"白菜", @"包心菜", @"菠菜", @"韭菜", @"冬瓜", @"胡萝卜", @"竹笋", nil];  
      
    self.m_data = arr;  
    [arr release];  
      
    [super viewDidLoad];  
}  
/* 
// Override to allow orientations other than the default portrait orientation. 
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { 
    // Return YES for supported orientations 
    return (interfaceOrientation == UIInterfaceOrientationPortrait); 
} 
*/  
- (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)viewDidUnload {  
    // Release any retained subviews of the main view.  
    // e.g. self.myOutlet = nil;  
    m_pPickerView = nil;  
    m_data = nil;  
    [super viewDidUnload];  
}  
  
- (void)dealloc {  
    [m_pPickerView release];  
    [m_data release];  
    [super dealloc];  
}  
#pragma mark -  
#pragma mark Picker View Data Source Methods  
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView  
{  
    return 1;  
}  
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component  
{  
    return [m_data count];  
}  
#pragma mark -  
#pragma mark Picker View Delegate Methods  
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component  
{  
    return [m_data objectAtIndex:row];  
}  
@end  

 4. 双击 PickerViewViewController.xib， 按下shift + command + L, 拖一个PickerView 放到View上。

 

    按下control 键同时从 File's Owner 拖动到 PickerView 控件上，连接输入口(IBOutlet).

 

    按下 command + 2, 把 dataSource和delegate 拖动到File's Owner上。

 

5. 运行后的效果如下: