［非凡程序员］手写UIDatePicker和UIPickerView

//
// ViewController.h
// 手写UIDatePicker
//
// Created by 非凡 程序员 on 15/11/13.
// Copyright (c) 2015年 非凡 程序员. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController

@property(nonatomic,strong)UIDatePicker *datePicker;
@end

//
// ViewController.m
// 手写UIDatePicker
//
// Created by 非凡 程序员 on 15/11/13.
// Copyright (c) 2015年 非凡 程序员. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
[super viewDidLoad];
//定义一个datePicker
_datePicker = [ [ UIDatePicker alloc ] initWithFrame:CGRectMake (10, 10, 100, 100) ] ;
//设置datePicker的样式
_datePicker.datePickerMode = UIDatePickerModeDateAndTime ;

//设置datePicker的时间差
_datePicker.minuteInterval = 6;
//设置datePicker的最小时间为当前时间
_datePicker.minimumDate = [ NSDate date ] ;

//对datePicker添加事件
[ _datePicker addTarget:self action:@selector(dateChange:) forControlEvents:UIControlEventValueChanged ] ;
//将控件添加在页面上
[ self.view addSubview:_datePicker ] ;
}
//当datePicker值发生改变会回调的自定义方法
- ( void ) dateChange : ( UIDatePicker * ) sender {
NSDate * date = _datePicker.date ; //获取datePicker的时间
NSLog ( @" %@ " , date )
;
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}

@end

//
// ViewController.h
// 手写UIPickerView
//
// Created by 非凡 程序员 on 15/11/13.
// Copyright (c) 2015年 非凡 程序员. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController<UIPickerViewDelegate,UIPickerViewDataSource>

@end

//
// ViewController.m
// 手写UIPickerView
//
// Created by 非凡 程序员 on 15/11/13.
// Copyright (c) 2015年 非凡 程序员. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
[super viewDidLoad];
//添加一个pickerView的步骤：
// 1.实例化一个pickerView对象
UIPickerView *picker=[[UIPickerView alloc]initWithFrame:[[UIScreen mainScreen]bounds]];
// 2，遵守两个协议，并设置代理
picker.dataSource=self;
picker.delegate=self;
// 3.将控件添加在页面上
[self.view addSubview:picker];

}

- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}
//实现两个必要方法。设置行数和组数
-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
return 4;
}
-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{
return 7;
}

@end