UIImagePickerController-IOS拍照和选择相册的详细解析（超级全）

转载自：http://blog.csdn.net/kingsley_cxz/article/details/9157093

1.UIImagePickerController的静态方法:

    imagepicker = [[UIImagePickerController alloc]init];

    //UIImagePickerController静态方法判断设备是否支持照相机／图片库／相册功能

    /*

     typedef NS_ENUM(NSInteger, UIImagePickerControllerSourceType) {

     UIImagePickerControllerSourceTypePhotoLibrary,

     UIImagePickerControllerSourceTypeCamera,

     UIImagePickerControllerSourceTypeSavedPhotosAlbum

     };

     */

    BOOL isCameraSupport = [UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera];

    NSLog(@"support camera:%d",isCameraSupport);

    

    //UIImagePickerController静态方法判断设备是否支持前置摄像头／后置摄像头

    /*

     typedef NS_ENUM(NSInteger, UIImagePickerControllerCameraDevice) {

     UIImagePickerControllerCameraDeviceRear,

     UIImagePickerControllerCameraDeviceFront

     };

     */

    BOOL isRearSupport = [UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceRear];

    NSLog(@"rear support:%d",isRearSupport);

    

    //UIImagePickerController静态方法判断设备是否支持前置摄像头闪光灯／后置摄像头闪光灯

    /*

     typedef NS_ENUM(NSInteger, UIImagePickerControllerCameraDevice) {

     UIImagePickerControllerCameraDeviceRear,

     UIImagePickerControllerCameraDeviceFront

     };

     */

    BOOL isFlushSupport = [UIImagePickerController isFlashAvailableForCameraDevice:UIImagePickerControllerCameraDeviceRear];

    NSLog(@"rear flash support:%d",isFlushSupport);

    

    //UIImagePickerController静态方法返回前置摄像头／后置摄像头支持的拍摄类型

    /*

     typedef NS_ENUM(NSInteger, UIImagePickerControllerCameraDevice) {

     UIImagePickerControllerCameraDeviceRear,

     UIImagePickerControllerCameraDeviceFront

     };

     */

    //返回类型有照片和视频

    /*

     enum {

     UIImagePickerControllerCameraCaptureModePhoto,

     UIImagePickerControllerCameraCaptureModeVideo

     };

     typedef NSUInteger UIImagePickerControllerCameraCaptureMode;

     */

    NSArray* captureModes = [UIImagePickerController availableCaptureModesForCameraDevice:UIImagePickerControllerCameraDeviceRear];

    for (NSNumber* mode in captureModes) {

        NSLog(@"capture modes:%d",[mode integerValue]);

    }

    

    //UIImagePickerController静态方法返回照相机／相册／照片库所支持的媒体类型

    /*

     typedef NS_ENUM(NSInteger, UIImagePickerControllerSourceType) {

     UIImagePickerControllerSourceTypePhotoLibrary,

     UIImagePickerControllerSourceTypeCamera,

     UIImagePickerControllerSourceTypeSavedPhotosAlbum

     };

     */

    //返回类型有kUTTypeMovie,kUTTypeImage，其他类型均在<MobileCoreServices/MobileCoreServices.h>下

    NSArray* mediaTypes = [UIImagePickerController availableMediaTypesForSourceType:UIImagePickerControllerSourceTypeCamera];

    for (NSString* type in mediaTypes) {

        NSLog(@"media types:%@",type);

    }

2.UIImagePickerController属性详解：

    //指定使用照相机模式,可以指定使用相册／照片库

    imagepicker.sourceType = UIImagePickerControllerSourceTypeCamera;

    //设置当拍照完或在相册选完照片后，是否跳到编辑模式进行图片剪裁。只有当showsCameraControls属性为true时才有效果

    imagepicker.allowsEditing = YES;

    //设置拍照时的下方的工具栏是否显示，如果需要自定义拍摄界面，则可把该工具栏隐藏

    imagepicker.showsCameraControls  = YES;

    //设置使用后置摄像头，可以使用前置摄像头

    imagepicker.cameraDevice = UIImagePickerControllerCameraDeviceRear;

    //设置闪光灯模式

    /*

     typedef NS_ENUM(NSInteger, UIImagePickerControllerCameraFlashMode) {

     UIImagePickerControllerCameraFlashModeOff  = -1,

     UIImagePickerControllerCameraFlashModeAuto = 0,

     UIImagePickerControllerCameraFlashModeOn   = 1

     };

     */

    imagepicker.cameraFlashMode = UIImagePickerControllerCameraFlashModeAuto;

    //设置相机支持的类型，拍照和录像

    imagepicker.mediaTypes = @[(NSString*)kUTTypeImage,(NSString*)kUTTypeMovie];

    //设置拍摄时屏幕的view的transform属性，可以实现旋转，缩放功能

   // imagepicker.cameraViewTransform = CGAffineTransformMakeRotation(M_PI*45/180);

   // imagepicker.cameraViewTransform = CGAffineTransformMakeScale(1.5, 1.5);

    //所有含有cameraXXX的属性都必须要sourceType是UIImagePickerControllerSourceTypeCamera时设置才有效果，否则会有异常

    //设置UIImagePickerController的代理

    imagepicker.delegate = self;

-(void)showCamera{

    //用模态方式呈现imagepicker

    [self presentModalViewController:imagepicker animated:YES];

}

使用 imagepicker.cameraViewTransform = CGAffineTransformMakeRotation(M_PI*45/180);旋转45度的效果：

使用imagepicker.cameraViewTransform
= CGAffineTransformMakeScale(1.5, 1.5);全屏的效果，同时imagepicker.showsCameraControls  =NO;隐藏工具栏：

使用imagepicker.allowsEditing
= YES;出现的图片编辑效果，只有当imagepicker.showsCameraControls 
= YES;才有效果：

使用 imagepicker.mediaTypes
= @[(NSString*)kUTTypeImage,(NSString*)kUTTypeMovie];支持拍照和视频的前后对比效果：

3.UIImagePickerController回调详解：

//成功获得相片还是视频后的回调

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{

    //通过UIImagePickerControllerMediaType判断返回的是照片还是视频

    NSString* type = [info objectForKey:UIImagePickerControllerMediaType];

    //如果返回的type等于kUTTypeImage，代表返回的是照片,并且需要判断当前相机使用的sourcetype是拍照还是相册

    if ([type isEqualToString:(NSString*)kUTTypeImage]&&picker.sourceType==UIImagePickerControllerSourceTypeCamera) {

        //获取照片的原图

        UIImage* original = [info objectForKey:UIImagePickerControllerOriginalImage];

        //获取图片裁剪的图

        UIImage* edit = [info objectForKey:UIImagePickerControllerEditedImage];

        //获取图片裁剪后，剩下的图

        UIImage* crop = [info objectForKey:UIImagePickerControllerCropRect];

        //获取图片的url

        NSURL* url = [info objectForKey:UIImagePickerControllerMediaURL];

        //获取图片的metadata数据信息

        NSDictionary* metadata = [info objectForKey:UIImagePickerControllerMediaMetadata];

        //如果是拍照的照片，则需要手动保存到本地，系统不会自动保存拍照成功后的照片

        UIImageWriteToSavedPhotosAlbum(edit, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);

    }else{

    

    }

    //模态方式退出uiimagepickercontroller

    [imagepicker dismissModalViewControllerAnimated:YES];

}
//取消照相机的回调

- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker{

    //模态方式退出uiimagepickercontroller

    [imagepicker dismissModalViewControllerAnimated:YES];

}
//保存照片成功后的回调

- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error

  contextInfo:(void *)contextInfo{

    

    NSLog(@"saved..");

}

4.自定义相机拍照画面：

   //设置拍照时的下方的工具栏是否显示，如果需要自定义拍摄界面，则可把该工具栏隐藏

    imagepicker.showsCameraControls  = NO;

    UIToolbar* tool = [[UIToolbar alloc]initWithFrame:CGRectMake(0, self.view.frame.size.height-55, self.view.frame.size.width, 75)];

    tool.barStyle = UIBarStyleBlackTranslucent;

    UIBarButtonItem* cancel = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:@selector(cancelCamera)];

    UIBarButtonItem* add = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemSave target:self action:@selector(savePhoto)];

    [tool setItems:[NSArray arrayWithObjects:cancel,add, nil]];

   //把自定义的view设置到imagepickercontroller的overlay属性中

   imagepicker.cameraOverlayView = tool;

-(void)cancelCamera{

    [imagepicker dismissModalViewControllerAnimated:YES];

}

-(void)savePhoto{

    //拍照，会自动回调- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info，对于自定义照相机界面，拍照后回调可以不退出实现连续拍照效果

    [imagepicker takePicture];

}

5.UIImagePickerController是继承UINavigationController,所以可以push和pop一些viewcontroller进行导航效果。例如，自定义照相机画面的时候可以在拍摄完后push一个viewcontroller用于对照片进行编辑。