IOS开发（3）之UIPickerView控件

1 前言
UIPickerView(选择器)也是出镜率相当高的控件，类似与HTML中的Select，今天我们就一起来学习一下这个控件。

2 UIPickerView简介

关键代码：

.h文件：

[plain]
#import <UIKit/UIKit.h>

//需要实现UIPickerViewDataSource,UIPickerViewDelegate协议
@interface ZYViewController : UIViewController<UIPickerViewDataSource,UIPickerViewDelegate>

@property(nonatomic,strong) UIPickerView *myPicker;

@end

#import <UIKit/UIKit.h>

//需要实现UIPickerViewDataSource,UIPickerViewDelegate协议
@interface ZYViewController : UIViewController<UIPickerViewDataSource,UIPickerViewDelegate>

@property(nonatomic,strong) UIPickerView *myPicker;

@end.m文件：

[plain]
@implementation ZYViewController

@synthesize myPicker;

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.view.backgroundColor = [UIColor whiteColor];

    self.myPicker = [[UIPickerView alloc] init];
    self.myPicker.dataSource = self;
    self.myPicker.center = self.view.center;

    self.myPicker.delegate = self;
    //设置选择器的水平的阴影效果
    self.myPicker.showsSelectionIndicator = YES;

    [self.view addSubview:self.myPicker];
}

// returns the number of 'columns' to display.
//为选择器添加组建，如果需要多个组建，可以修改该方法体
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{
    NSInteger result = 0;
    if([pickerView isEqual:self.myPicker]){
        result = 1;
    }
    return result;
}

// returns the # of rows in each component..
//定义一个组件中有多少个选项，如果想为想象添加值，需要修改该方法体
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
    NSInteger result = 0;
    if ([pickerView isEqual:self.myPicker]) {
        result = 10;
    }
    return result;
}

//UIPickerViewDelegate
//设置UIPickerView的每个组件的标题
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component{
    NSString *result = nil;
    if ([pickerView isEqual:self.myPicker]) {
        result = [NSString stringWithFormat:@"Row %ld",(long)row+1];
    }
    return result;
}

//选择时候触发的事件
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
    NSLog(@"result: You selected Row%ld",(long)row+1);
}

@implementation ZYViewController

@synthesize myPicker;

- (void)viewDidLoad
{
    [super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
    self.view.backgroundColor = [UIColor whiteColor];

    self.myPicker = [[UIPickerView alloc] init];
    self.myPicker.dataSource = self;
    self.myPicker.center = self.view.center;

    self.myPicker.delegate = self;
    //设置选择器的水平的阴影效果
    self.myPicker.showsSelectionIndicator = YES;

    [self.view addSubview:self.myPicker];
}

// returns the number of 'columns' to display.
//为选择器添加组建，如果需要多个组建，可以修改该方法体
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{
    NSInteger result = 0;
    if([pickerView isEqual:self.myPicker]){
        result = 1;
    }
    return result;
}

// returns the # of rows in each component..
//定义一个组件中有多少个选项，如果想为想象添加值，需要修改该方法体
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
    NSInteger result = 0;
    if ([pickerView isEqual:self.myPicker]) {
        result = 10;
    }
    return result;
}

//UIPickerViewDelegate
//设置UIPickerView的每个组件的标题
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component{
    NSString *result = nil;
    if ([pickerView isEqual:self.myPicker]) {
        result = [NSString stringWithFormat:@"Row %ld",(long)row+1];
    }
    return result;
}

//选择时候触发的事件
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
NSLog(@"result: You selected Row%ld",(long)row+1);
}
运行结果：

当选择某个选项时候控制台运行结果：

2013-04-22 15:27:21.163 UIPickerViewTest[649:c07] result: You selected Row1

2013-04-22 15:31:49.433 UIPickerViewTest[649:c07] result: You selected Row2

2013-04-22 15:31:51.327 UIPickerViewTest[649:c07] result: You selected Row4

补充：移动开发 , IOS ,