UIImagePickerController照片选取器

记录于2013/7/4

加入框架： 

MobileCoreServices.framework 

MediaPlayer.framework

导入头文件：

#import <MediaPlayer/MediaPlayer.h>

#import <MobileCoreServices/UTCoreTypes.h> 

---

代码： 

if(![UIImagePickerControllerisSourceTypeAvailable:
          UIImagePickerControllerSourceTypeCamera]) {
        takePictureButton.hidden = YES; //无摄像头隐藏改按钮
    }
    imageFrame = imageView.frame;

实现：

- (IBAction)shootPictureOrVideo:(id)sender {
    [selfgetMediaFromSource:UIImagePickerControllerSourceTypeCamera];
}
- (IBAction)selectExistingPictureOrVideo:(id)sender {
    [selfgetMediaFromSource:UIImagePickerControllerSourceTypePhotoLibrary];
}
#pragma mark UIImagePickerController delegate methods
- (void)imagePickerController:(UIImagePickerController *)picker
didFinishPickingMediaWithInfo:(NSDictionary *)info {
    self.lastChosenMediaType = [info objectForKey:UIImagePickerControllerMediaType];
    if ([lastChosenMediaTypeisEqual:(NSString *)kUTTypeImage]) {
        UIImage *chosenImage = [info objectForKey:UIImagePickerControllerEditedImage];
        UIImage *shrunkenImage = shrinkImage(chosenImage, imageFrame.size);
        self.image = shrunkenImage;
    } elseif ([lastChosenMediaTypeisEqual:(NSString *)kUTTypeMovie]) {
        self.movieURL = [info objectForKey:UIImagePickerControllerMediaURL];
    }
    [picker dismissModalViewControllerAnimated:YES];
}
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker {
    [picker dismissModalViewControllerAnimated:YES];
}
#pragma mark  -
//类扩张
staticUIImage *shrinkImage(UIImage *original, CGSize size) {
    //设备物理屏幕像素倍数
    CGFloat scale = [UIScreenmainScreen].scale;
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();

    CGContextRef context = CGBitmapContextCreate(NULL, size.width * scale,
                                                 size.height * scale, , , colorSpace, kCGImageAlphaPremultipliedFirst);
    CGContextDrawImage(context,
                       CGRectMake(, , size.width * scale, size.height * scale),
                       original.CGImage);
    CGImageRef shrunken = CGBitmapContextCreateImage(context);
    UIImage *final = [UIImageimageWithCGImage:shrunken];

    CGContextRelease(context);
    CGImageRelease(shrunken);

    return final;
}
- (void)updateDisplay {
    if ([lastChosenMediaTypeisEqual:(NSString *)kUTTypeImage]) {
        imageView.image = image;
        imageView.hidden = NO;
        moviePlayerController.view.hidden = YES;
    } elseif ([lastChosenMediaType isEqual:(NSString *)kUTTypeMovie]) {
        [self.moviePlayerController.view removeFromSuperview];
        self.moviePlayerController = [[MPMoviePlayerControlleralloc]
                                      initWithContentURL:movieURL];
        moviePlayerController.view.frame = imageFrame;
        moviePlayerController.view.clipsToBounds = YES;
        [self.viewaddSubview:moviePlayerController.view];
        imageView.hidden = YES;
    }
}
- (void)getMediaFromSource:(UIImagePickerControllerSourceType)sourceType {
    //判断设备是否具有该功能
    NSArray *mediaTypes = [UIImagePickerController
                           availableMediaTypesForSourceType:sourceType];
    if ([UIImagePickerControllerisSourceTypeAvailable:
         sourceType] && [mediaTypes count] > ) {
        NSArray *mediaTypes = [UIImagePickerController
                               availableMediaTypesForSourceType:sourceType];
        UIImagePickerController *picker =
        [[UIImagePickerController alloc] init];
        picker.mediaTypes = mediaTypes;
        picker.delegate = self;
        picker.allowsEditing = YES;
        picker.sourceType = sourceType;
        [self presentModalViewController:picker animated:YES];
    } else {
        //设备不支持该功能，弹出提示
        UIAlertView *alert = [[UIAlertView alloc]
                              initWithTitle:@"Error accessing media"
                              message:@"Device doesn’t support that media source."
                              delegate:nil
                              cancelButtonTitle:@"Drat!"
                              otherButtonTitles:nil];
        [alert show];
    }
}