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iOS

Posted by James Atlee
James Atlee
203 Points

Camera View Controller

What code do I need to implement to allow the user to have the option to select a picture from their camera roll. Instead of having to take a picture.

5 Answers

Stone Preston
Stone Preston
42,016 Points

WIthout implementing a custom camera interface, id say the simplest thing to do would be to use an action sheet.

you can use an action sheet to present two choices, take photo or choose from photo library. to do this you need to conform to the action sheet delegate protocol

@interface SomeViewController : UIViewController<UIActionSheetDelegate>

then whenever you want to present the action sheet

UIActionSheet *actionSheet = [[UIActionSheet alloc] initWithTitle:nil delegate:self cancelButtonTitle:@"Cancel" destructiveButtonTitle:nil otherButtonTitles:@"Take Photo", @"Choose from library", nil];

//set the actionsheet delegate
 actionSheet.delegate = self;

//show the action sheet from tab bar
[actionSheet showFromTabBar:self.tabBarController.tabBar];

and implement the following delegate method

-(void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {

    //user clicked take photo
    if (buttonIndex == 0 ) {

       //change your image pickers source type to camera

       self.imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;

        [self presentViewController:self.imagePicker animated:NO completion:nil];


    }

     //user clicked choose from library
     if (buttonIndex == 1) {

            //change your image pickers source type to photo library

      self.imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

        [self presentViewController:self.imagePicker animated:NO completion:nil];

   }
}
James Atlee
James Atlee
203 Points

The action sheet works, but when I click on one of the buttons the app crashes

Stone Preston
Stone Preston
42,016 Points

what error are you getting?

James Atlee
James Atlee
203 Points
James Atlee
James Atlee
203 Points

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Application tried to present a nil modal view controller on target <FriendsViewController: 0x14e640b0>.'

Stone Preston
Stone Preston
42,016 Points

make sure you set up the imagePicker property in viewDidLoad. sounds like it didnt get initialized or something

James Atlee
James Atlee
203 Points
James Atlee
James Atlee
203 Points

How would I set that up in the viewDidLoad?

Stone Preston
Stone Preston
42,016 Points 
self.imagePicker = [[UIImagePickerController alloc] init];
self.imagePicker.delegate = self;
self.imagePicker.allowsEditing = NO;

something along those lines.

James Atlee
James Atlee
203 Points
James Atlee
James Atlee
203 Points

thank you! works great

Stone Preston
Stone Preston
42,016 Points

awesome. glad you got it working

James Atlee
James Atlee
203 Points
James Atlee
James Atlee
203 Points

I have another question. After i am done selecting an image from the the photo library, I want it to transfer over to my recipients view controller What code would I need to implement to get to do that?