UIImagePickerController在iPhone和iPad上的区别

在iPhone中获取照片库的常用方法如下：

UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];

if ([UIImagePickerController isSourceTypeAvailable:

UIImagePickerControllerSourceTypePhotoLibrary]) {

imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

imagePicker.delegate = self;

[imagePicker setAllowsEditing:NO];

[self presentModalViewController:imagePicker animated:YES];

[imagePicker release];

} else {

UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:@"Error accessing photo library!" delegate:nil cancelButtonTitle:@"Close" otherButtonTitles:nil];

[alert show];

[alert release];

}



这在iPhone下操作是没有问题的，但在iPad下就会有问题了，运行时会报出下面的错误：



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。具体的实现如下：



UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];

if ([UIImagePickerController isSourceTypeAvailable:

UIImagePickerControllerSourceTypePhotoLibrary]) {

imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

imagePicker.delegate = self;

[imagePicker setAllowsEditing:NO];

UIPopoverController *popover = [[UIPopoverController alloc] initWithContentViewController:imagePicker];

self.popoverController = popover;

[popoverController presentPopoverFromRect:CGRectMake(0, 0, 300, 300) inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];

[popover release];

[imagePicker release];

} else {

UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:@"Error accessing photo library!" delegate:nil cancelButtonTitle:@"Close" otherButtonTitles:nil];

[alert show];

[alert release];

}

转自：http://2015.iteye.com/blog/1340797