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iOS Build a Self-Destructing Message iPhone App Capturing Photo and Video Using UIImagePickerController Saving the Media

Posted by Jiance Tong
Jiance Tong
3,367 Points

Get problem when try to save the image

when I try to redo the code for the self-destruction message app, I get problem when try to realize the function to store the image. If I pick the image in the photo album, the application will crash. Following is my code:

(void) imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    NSString * mediaType = [info objectForKey:UIImagePickerControllerOriginalImage]; 
  if ([mediaType isEqualToString:(NSString *)kUTTypeImage]) { 
      //image is selected
        self.image=[info objectForKey:UIImagePickerControllerOriginalImage];
        if(self.imagePicker.sourceType == UIImagePickerControllerSourceTypeCamera){
            UIImageWriteToSavedPhotosAlbum(self.image, nil, nil, nil);
        }
    }
    else{
        //video is selected
        NSURL * url=[info objectForKey:UIImagePickerControllerMediaURL];
        self.videoPath =[url path];
        if(self.imagePicker.sourceType == UIImagePickerControllerSourceTypeCamera){
            if (UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(self.videoPath)) {
                UISaveVideoAtPathToSavedPhotosAlbum(self.videoPath, nil, nil, nil);
            }  
        }
    }
    [self dismissViewControllerAnimated:YES completion:nil];
}

When I debug the function, I find when the NSString type variable mediaType is used in the if statement: if ([mediaType isEqualToString:(NSString *)kUTTypeImage]) , the debug window shows that the type of mediatype is UIImage.

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

to format code oyu need to use 3 backticks ( ` ) not three single quotes ( ' ). the backtick is located below the escape key on my keyboard. The same key as the ~

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

here is your error:

NSString * mediaType = [info objectForKey:UIImagePickerControllerOriginalImage];

needs to be 

NSString *mediaType = [info objectForKey:UIImagePickerControllerMediaType];
Jiance Tong
Jiance Tong
3,367 Points

Thanks again, Stone. BTW, do u know how to format my code in the discussion board? I try the way: ''' code ''' But it doesn't work.

Jiance Tong
Jiance Tong
3,367 Points

Oh, u just anser my question. Thanks very much!

Jiance Tong
Jiance Tong
3,367 Points

Oh, u just anser my question. Thanks very much!