访问系统相册

//  ViewController.m

//  访问系统相册

//

//  Created by lanouhn on 16/7/12.

//  Copyright © 2016年 lanouhn. All rights reserved.

//

#import "ViewController.h"

//遵守协议

@interface ViewController ()

@property(nonatomic,strong)UIButton *userbtn;

@end

@implementation ViewController

- (void)viewDidLoad {

   [super viewDidLoad];

//  所有的能看得到的UI控件创建初始化呢方式都可以采用alloc initWithFrame

   self.userbtn = [[UIButton alloc]initWithFrame:CGRectMake(30, 60, 80, 80)];

//  设置颜色

   self.userbtn.backgroundColor = [UIColor redColor];

//  设置圆形半径

   self.userbtn.layer.cornerRadius = 40;

   self.userbtn.layer.masksToBounds = YES;

//  添加点击事件：去访问系统相册

   [self.userbtn addTarget:self action:@selector(setUserImage) forControlEvents:(UIControlEventTouchUpInside)];

//  将按钮添加到屏幕上来

   [self.view addSubview:self.userbtn];

   }

//访问系统相册

-(void)setUserImage

{

   UIImagePickerController *imagePicker = [[UIImagePickerController alloc]init];

//设置代理，到@interface后面遵守协议

   imagePicker.delegate = self;

//弹出系统相册

   [self presentViewController:imagePicker animated:YES completion:nil];

}

//这个方法是协议UIImagePickerControllerDelegate里面的，选择图片结束的时候就会自动调用

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(nullable NSDictionary *)editingInfo

{

//  设置头像

   [self.userbtn setBackgroundImage:image forState:(UIControlStateNormal)];

//  将系统相册消失掉

   [picker

    dismissViewControllerAnimated:YES completion:nil];

}

- (void)didReceiveMemoryWarning {

   [super didReceiveMemoryWarning];

   // Dispose of any resources that can be recreated.