iphone和ipad拍照功能的实现

在iphone和ipad中，拍照的实现是不同的。

在iphone中：

if([UIImagePickerController   issourceTypeAvailable:UIImagePickerControllersourceTypeCamera])

{

picker = [[UIImagePickerController alloc] init];

picker.delegate = self;

picker.sourCEType = UIImagePickerControllersourceTypeCamera;

picker.allowsEdiTing = NO;

picker.showsCameraControllers = YES;

  [self presentModalViewController:m_imagePicker animated:YES];
  [m_imagePicker release];
}else {
  UIAlertView *alert = [[UIAlertView alloc]initWithtitle:nil message:@”" delegate:nil cancelButtontitle:@”Close” otherButtontitles:nil];
  [alert show];
  [alert release];
}

即可调用相机拍照，但在ipad中，需要通过UIPopoverController来实现，或者通过openGL也可实现，如下

if([UIImagePickerController issourceTypeAvailable:UIImagePickerControllersourceTypeCamera])

{

picker = [[UIImagePickerController alloc] init];

picker.delegate = self;

picker.sourCEType = UIImagePickerControllersourceTypeCamera;

picker.allowsEdiTing = NO;

picker.modalPresentationStyle = UIModalPresentationCurrentContext;

UIViewController * myViewController = [[UIViewController alloc] init];

[[[CCDirector sharedDirector] openGLView] addSubview:myViewController.view];

[myViewController presentModalViewController:picker animated:YES];

[myViewController setModalPresentationStyle:UIModalPresentationCurrentContext];

}

对于拍照的控制需要使用UIImagePickerControllerDelegate的三个方法

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image ediTingInfo:(NSDictionary *)ediTingInfo

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

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

一般来说，如果item中包含image和video时，需要使用didFinishPickingMediaWithInfo的方法，拍照后在未保存图片之前，照片的信息会存放在缓存中，这时通过保存图片信息的字典中内容可以获取所拍照片，实现如下

- (void) imagePickerController:(UIImagePickerController *)picker1 didFinishPickingMediaWithInfo:(NSDictionary *)info {

UIImage * photo = [info objectForKey:@"UIImagePickerControllerOriginalImage"];

}

所得的照片有一个只读的属性imageOrientation，它记录照片拍摄时的方向，在某些情况下，这个属性是非常有用的。还有一点容易忽略的东西，使用ipad拍的照片大小是960*720，而不是1024*768。