iOS调用系统相册

话不多说,直接上代码

UIButton * button  = [UIButton buttonWithType:UIButtonTypeSystem];//这是用来调用相册的button
button.frame = CGRectMake(100, 100, 100, 100);
button.backgroundColor = [UIColor greenColor];
[button addTarget:self action:@selector(buttonAction) forControlEvents:(UIControlEventTouchUpInside)];
[self.view addSubview:button];
    
    
UIImageView * imageView = [[UIImageView alloc]init];//展示相片的视图
imageView.frame = CGRectMake(100, 220, 200, 200);
imageView.backgroundColor = [UIColor brownColor];
imageView.tag = 101;
[self.view addSubview: imageView];

- (void)buttonAction
{
    //创建图片控制器
    UIImagePickerController * pc = [[[UIImagePickerController alloc]init] autorelease];
    pc.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
//    pc.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;//相册的另一种视图形式
//    pc.sourceType = UIImagePickerControllerSourceTypeCamera这时候是照相使用的，使用的时候先判断能不能使用相机，模拟机不能拍照，调用相册不会用到

    
    //是否允许被编辑
    pc.allowsEditing = YES;
    
    //代理，这时候遵循一下代理
    pc.delegate = self;//因为delegete遵守了两个协议，这里只需要一个协议，只遵守了一个
    
    
    //animated是否要动画
    [self presentViewController:pc animated:YES completion:^{
        
    }];
    

}

UIImagePickerControllerDelegate协议里面的方法，注意先去遵循协议，才会有这个方法的提示

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    //把得到的相册传递为标记的ImageView
    UIImageView * img = (UIImageView *)[self.view viewWithTag:101];
    img.image = info[UIImagePickerControllerEditedImage];
    NSLog(@"%@",info);
    
    //退出
    [self dismissViewControllerAnimated:YES completion:^{

    } ];
    
}