效果圖

如圖，通過點(diǎn)擊button進(jìn)入UIalertcontroller，選擇相冊進(jìn)入系統(tǒng)相冊選擇圖片并上傳到imageview上顯示。話不多說，上代碼：

#import "ViewController.m"

#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>
#import <MediaPlayer/MediaPlayer.h>
@interface ViewController ()<UIImagePickerControllerDelegate, UINavigationControllerDelegate>{
    
    UIImagePickerController *_imagePickerController;
}
@property (strong, nonatomic) IBOutlet UIImageView *imgv;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    _imagePickerController = [[UIImagePickerController alloc] init];
    _imagePickerController.delegate = self;
    //跳轉(zhuǎn)動畫效果
    _imagePickerController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
    _imagePickerController.allowsEditing = YES;
    
}

- (IBAction)butt:(id)sender {
    
    UIAlertController *alertCtl =[[UIAlertController alloc]init];
    
    UIAlertAction *cancel =[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
        NSLog(@"cancel");
    }];
    UIAlertAction *xiangji =[UIAlertAction actionWithTitle:@"相機(jī)" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        NSLog(@"xiangji");
        
        [self openCamera];
    }];
    UIAlertAction *xiangce =[UIAlertAction actionWithTitle:@"相冊" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        NSLog(@"xiangce");
        
        [self openPhotoLibrary];
    }];
    
    [alertCtl addAction:cancel];
    [alertCtl addAction:xiangji];
    [alertCtl addAction:xiangce];
    
    [self presentViewController:alertCtl animated:YES completion:nil];
}

/**
 *  調(diào)用照相機(jī)
 */
- (void)openCamera
{

    //判斷是否可以打開照相機(jī)
    if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]){
        //攝像頭
        _imagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera;
        [self presentViewController:_imagePickerController animated:YES completion:nil];
    }
    else{
        NSLog(@"沒有攝像頭");
    }
}
/**
 *  打開相冊
 */
-(void)openPhotoLibrary{

    // 進(jìn)入相冊
    if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary])
    {
        _imagePickerController.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
        [self presentViewController:_imagePickerController animated:YES completion:^{
            NSLog(@"打開相冊");
        }];
    }else{
        NSLog(@"不能打開相冊");
    }
}
#pragma mark - UIImagePickerControllerDelegate
// 拍照完成回調(diào)
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(nullable NSDictionary<NSString *,id> *)editingInfo NS_DEPRECATED_IOS(2_0, 3_0){
    
    NSLog(@"finish..");
    if(picker.sourceType == UIImagePickerControllerSourceTypeCamera)
    {
        //圖片存入相冊
        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
    }
    self.imgv.image =image;
    [self dismissViewControllerAnimated:YES completion:nil];
}

//進(jìn)入拍攝頁面點(diǎn)擊取消按鈕
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker{
    [self dismissViewControllerAnimated:YES completion:nil];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

接下來在info.plist文件中添加NSPhotoLibraryUsageDescription和NSCameraUsageDescription用于獲取手機(jī)的相機(jī)和相冊的權(quán)限，運(yùn)行。

需要注意的是，模擬器上并不支持相機(jī)，選擇相冊，選擇圖片，完成。

完成.png