UIImagePickerController在iPhone和iPad中用法的一点不同
UIImagePickerController *m_imagePicker = [[UIImagePickerController alloc] init];
if ([UIImagePickerController isSourceTypeAvailable:
UIImagePickerControllerSourceTypePhotoLibrary]) {
m_imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
m_imagePicker.delegate = self;
// [m_imagePicker.navigationBar.subviews];
[m_imagePicker setAllowsEditing:NO];
//m_imagePicker.allowsImageEditing = NO;
[self presentModalViewController:m_imagePicker animated:YES];
[m_imagePicker release];
}else {
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:@"Error accessing photo library!" delegate:nil cancelButtonTitle:@"Close" otherButtonTitles:nil];
[alert show];
[alert release];
}
这对iPhone的操作是没有问题的。但是当我们在iPad环境中却有问题了，当我们运行时会报如下错误：
Terminating app due to uncaught exception 'NSinvalidargumentexception',reason: 'On iPad,UIImagePickerController must be presented via UIPopoverController'
所以我们必须通过UIPopoverController来实现才行。具体实现如下：
UIImagePickerController *m_imagePicker = [[UIImagePickerController alloc] init]; if ([UIImagePickerController isSourceTypeAvailable: UIImagePickerControllerSourceTypePhotoLibrary]) { m_imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary; m_imagePicker.delegate = self; [m_imagePicker setAllowsEditing:NO]; UIPopoverController *popover = [[UIPopoverController alloc] initWithContentViewController:m_imagePicker]; self.popoverController = popover; //popoverController.delegate = self; [popoverController presentPopoverFromrect:CGRectMake(0,300,300) inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES]; //[self presentModalViewController:m_imagePicker animated:YES]; [popover release]; [m_imagePicker release]; }else { UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:@"Error accessing photo library!" delegate:nil cancelButtonTitle:@"Close" otherButtonTitles:nil]; [alert show]; [alert release]; } 这里需要注意，对局部UIPopoverController对象popover我们赋给了一个全局的UIPopoverController对象popoverController。而不能直接调用popover。因为在popover对象还可见时，是不能够被释放的。
