访问系统相册的创建

       使用OS的系统，在使用OC语言的基础上创建访问系统相册，就是创建其他应用程序的部分语句，也就是在苹果系统上QQ的登录系统的一部分。

#import"ViewController.h"

//遵守协议

@interfaceViewController()

@property(nonatomic,strong)UIButton*userBtu;

@end

@implementationViewController

- (void)viewDidLoad {

[superviewDidLoad];

//所有的能看得到的UI控件创建初始化方式都可以采用allocinitWithFrame

self.userBtu= [[UIButtonalloc]initWithFrame:CGRectMake(30,60,80,80)];

//设置颜色

self.userBtu.backgroundColor= [UIColorredColor];

//将图片加载到内存中

UIImage*image = [UIImageimageNamed:@"login_header"];

//将加到内存后的图片设置为背景图片

[self.userBtusetBackgroundImage:imageforState:(UIControlStateNormal)];

//设置圆形半径

self.userBtu.layer.cornerRadius=40;

//超过内切圆的图片给切割掉

self.userBtu.layer.masksToBounds=YES;

//添加点击事件：去访问系统相册

[self.userBtuaddTarget:selfaction:@selector(setUserImage)forControlEvents:(UIControlEventTouchUpInside)];

//将按钮添加到屏幕上面来

[self.viewaddSubview:self.userBtu];

}

//访问系统相册

-(void)setUserImage

{

UIImagePickerController*imagePicker = [[UIImagePickerControlleralloc]init];

//设置代理,到@interface后面

UIImagePickerControllerDelegate>

imagePicker.delegate=self;

//弹出相册

[selfpresentViewController:imagePickeranimated:YEScompletion: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:(nullableNSDictionary *)editingInfo

{

//设置头像

[self.userBtusetBackgroundImage:imageforState:(UIControlStateNormal)];

//将系统相册消失掉

[pickerdismissViewControllerAnimated:YEScompletion:nil];

}

- (void)didReceiveMemoryWarning {

[superdidReceiveMemoryWarning];

// Dispose of any

resources that can be recreated.

}

@end