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!!!!