UIImagePickerController的用法

在实际的APP开发中,我们经常会见到应用的这样的功能 :需要选取手机相册的照片,还有选取视频,拍视频和照相的操作.

在iOS开发中,实现以上的功能就需要用到 UIImagePickerController.

现将 UIImagePickerController的基本用法总结如下 :

#import "ViewController.h"

@interface ViewController ()<UIImagePickerControllerDelegate,UINavigationControllerDelegate>

//拍照
- (IBAction)takePhoto:(id)sender;

//拍电影
- (IBAction)takeMovie:(id)sender;

@property (weak, nonatomic) IBOutlet UIImageView *imgView;

//选择照片
- (IBAction)selectPhoto:(id)sender;

//选择视频
- (IBAction)selectVideo:(id)sender;


@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    //UIImagePickerController.访问用户相册 2.拍照,拍视频
    
}

//1.选取照片
- (IBAction)selectPhoto:(id)sender {
    
    UIImagePickerController *imagePickerCtrl = [[UIImagePickerController alloc] init];
    
    /*
    UIImagePickerControllerSourceTypePhotoLibrary,获取相册中所有的文件
    UIImagePickerControllerSourceTypeCamera,摄像头
    UIImagePickerControllerSourceTypeSavedPhotosAlbum,系统内置相册
     */

    //资源类型(资源来自哪里,可以来相册,摄像头)
    imagePickerCtrl.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
    
    //设置代理
    imagePickerCtrl.delegate = self;
    
    //弹出控制器
    [self presentViewController:imagePickerCtrl animated:YES completion:^{
       
        //弹出控制器完成调用的方法
    }];
    
}
/**
 *
 * 2.选取视频
 */
- (IBAction)selectVideo:(id)sender {
    
     UIImagePickerController *imagePickerCtrl = [[UIImagePickerController alloc] init];
    
    imagePickerCtrl.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
    imagePickerCtrl.delegate = self;
    
    //指定媒体类型,图片(@"public.image"),视频(@"public.movie")
    imagePickerCtrl.mediaTypes = @[/*@"public.image",*/@"public.movie"];
    
    [self presentViewController:imagePickerCtrl animated:YES completion:NULL];
    
    
}

//3.拍照
- (IBAction)takePhoto:(id)sender {

    UIImagePickerController *imagePickerCtrl = [[UIImagePickerController alloc] init];
    
    imagePickerCtrl.delegate = self;
    
    //判断手机是否支持(前)摄像头
    if (![UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceFront]) {
        
        UIAlertView *alerView = [[UIAlertView alloc] initWithTitle:@"提示" message:@"手机太渣,没有摄像头" delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];
        [alerView show];
        
        return;
    }
    
    //指定资源来自摄像头
    imagePickerCtrl.sourceType = UIImagePickerControllerSourceTypeCamera;
    
    [self presentViewController:imagePickerCtrl animated:YES completion:NULL];
    

}

//4.拍视频
- (IBAction)takeMovie:(id)sender {
    
    UIImagePickerController *imagePickerCtrl = [[UIImagePickerController alloc] init];
    
    imagePickerCtrl.delegate = self;

    //指定资源来自摄像头
    imagePickerCtrl.sourceType = UIImagePickerControllerSourceTypeCamera;
    
    //设置资源类型
    imagePickerCtrl.mediaTypes = @[@"public.movie"];
    
    [self presentViewController:imagePickerCtrl animated:YES completion:NULL];
}

#pragma mark UIImagePickerControllerDelegate
//选取完视频,或者照片调用的协议方法(不管是拍照,选相册,拍视频,选视频,最终都会调用此方法)
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {

    NSLog(@"%@",info);
    
    //取出选择的照片
    UIImage *img = info[UIImagePickerControllerOriginalImage];
    
    //将选取的照片交给_imgView显示
    _imgView.image = img;
    
    
    //如果资源来自摄像头
    if (picker.sourceType == UIImagePickerControllerSourceTypeCamera) {
        
        //将图片存到相册中调用的方法  (苹果建议的写法:好像必须要这样写)
        //- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
        
        UIImageWriteToSavedPhotosAlbum(img, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);
    }
    
    //如果选中的是视频则可以通过UIImagePickerControllerMediaURL在字典中获取到选中的视频的URL
   
    //选取照片或视频后,关闭控制器
    [picker dismissViewControllerAnimated:YES completion:NULL];
    
}

//"取消"按钮被点击
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker {

    NSLog(@"被关闭了");
    [picker dismissViewControllerAnimated:YES completion:NULL];

}

- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo{
    
    NSLog(@"照片保存到相册成功");
}

@end

这种写法的缺点就是,选取图片的时候只能选取一张照片,如果要选取多张照片的话,就需要用到另外一种方法  AssetsLibrary

AssetsLibrary的基本用法随后更新!!!    记得关注我哟!!!!