Getting Screenshot of certain views to camera roll iOS - ios

Question

Hi I am still a beginner with Objective-C and am hoping someone can help me out. What I have created programmatically is a UIScrollView that has images inside that you can swipe across. Then I created a UIButton that when pressed is supposed to take a screenshot of the image subview the has been selected and then saves it to the camera roll (that part i'm not sure where to add in the code). The reason I want it to be a screenshot and not just the image is because I will later add UILabels on top of the images and I want those to appear in the saved screenshot as well. I am not quite sure which views to use in the saveWallpaper method and even if my current solution will work. I have looked at this answer Link to get the screenshot code to try for this implementation. Basically I want it to take a screenshot of everything besides the UIButton and save it to the camera roll. Any help or direction would be greatly appreciated. I could also try an approach where it takes a screenshot or captures certain elements and adds them together to be a single image. Thank you!
- (void)viewDidLoad
{
[super viewDidLoad];
int PageCount = 21;
NSMutableArray *arrImageName =[[NSMutableArray alloc]initWithObjects:#"1.png",#"2.png",#"3.png",#"4.png",#"5.png",#"6.png",#"7.png",#"8.png",#"9.png",#"10.png",#"11.png",#"12.png",#"13.png",#"14.png",#"15.png",#"16.png",#"17.png",#"18.png",#"19.png",#"20.png",#"21.png", nil];
scroller = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];
scroller.scrollEnabled=YES;
scroller.backgroundColor = [UIColor clearColor];
scroller.pagingEnabled = YES;
scroller.bounces = NO;
[self.view addSubview:scroller];
int width=scroller.frame.size.width;
int xPos=0;
for (int i=0; i<PageCount; i++)
{
UIImageView *ImgView = [[UIImageView alloc]initWithFrame:CGRectMake(xPos, 0, scroller.frame.size.width, scroller.frame.size.height)];
[ImgView setImage:[UIImage imageNamed:[arrImageName objectAtIndex:i]]];
[scroller addSubview:ImgView];
scroller.contentSize = CGSizeMake(width, 0);
width +=scroller.frame.size.width;
xPos +=scroller.frame.size.width;
}
UIButton *saveButton = [UIButton buttonWithType:UIButtonTypeCustom];
[saveButton addTarget:self
action:#selector(saveWallpaper:)
forControlEvents:UIControlEventTouchDown];
[saveButton setImage:[UIImage imageNamed:#"save.png"] forState: UIControlStateNormal];
[saveButton setImage:[UIImage imageNamed:#"savepressed.png"] forState: UIControlStateHighlighted];
saveButton.frame = CGRectMake([[UIScreen mainScreen] bounds].size.width/2, 396, 96.5, 42); //Make this in the center
[self.view addSubview:saveButton];
}
- (void)saveWallpaper:(id)sender
{
if ([[UIScreen mainScreen] respondsToSelector:#selector(scale)]) {
UIGraphicsBeginImageContextWithOptions(scroller.bounds.size, NO, [UIScreen mainScreen].scale);
}
else
{
UIGraphicsBeginImageContext(scroller.bounds.size);
[scroller.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData * data = UIImagePNGRepresentation(image);
[data writeToFile:#"foo.png" atomically:YES];
}
}

Answer 1

Rather than drawing the complete scroller view as in the following statement
[scroller.layer renderInContext:UIGraphicsGetCurrentContext()];
Draw the selected image and the text using drawInRect method. See this related post for reference.