IPhone: how to save a view as an image ??? (for example, what you draw)

Question

I found some sample teach you how to draw on iphone

but he doesn’t say how to save the view as an image?

Has anyone got an idea ???

Or any sample will be useful :)

In fact, I am trying to save the user signature as an image and upload it to the server.

thanks

Webber

Answer 1

UIView *view = // your view UIGraphicsBeginImageContext(view.bounds.size); [view.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); 

This gives an image that you can save with -

 NSData *imageData = UIImageJPEGRepresentation(image, 1.0); [imageData writeToFile:path atomically:YES]; 

where path is the location you want to save.

Answer 2

Here is a quick way to render any UIView as an image. It takes into account the version of iOS on which the device is running, and uses the appropriate method to obtain a representation of the UIView image.

In particular, there is now a better method (i.e. drawViewHierarchyInRect: afterScreenUpdates :) for taking a screenshot of a UIView on devices running iOS 7 or later, which, from what I read, is considered more compared to the renderInContext method .

Further information here: https://developer.apple.com/library/ios/documentation/uikit/reference/uiview_class/UIView/UIView.html#//apple_ref/doc/uid/TP40006816-CH3-SW217

EXAMPLE OF USE:

 #import <QuartzCore/QuartzCore.h> // don't forget to import this framework in file header. UIImage* screenshotImage = [self imageFromView:self.view]; //or any view that you want to render as an image. 

CODE:

 #define IS_OS_7_OR_LATER ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0) - (UIImage*)imageFromView:(UIView*)view { CGFloat scale = [UIScreen mainScreen].scale; UIImage *image; if (IS_OS_7_OR_LATER) { //Optimized/fast method for rendering a UIView as image on iOS 7 and later versions. UIGraphicsBeginImageContextWithOptions(view.bounds.size, YES, scale); [view drawViewHierarchyInRect:view.bounds afterScreenUpdates:YES]; image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } else { //For devices running on earlier iOS versions. UIGraphicsBeginImageContextWithOptions(view.bounds.size,YES, scale); [view.layer renderInContext:UIGraphicsGetCurrentContext()]; image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } return image; } 

Answer 3

In MonoTouch / C # as an extension method:

 public static UIImage ToImage(this UIView view) { try { UIGraphics.BeginImageContext(view.ViewForBaselineLayout.Bounds.Size); view.Layer.RenderInContext(UIGraphics.GetCurrentContext()); return UIGraphics.GetImageFromCurrentImageContext(); } finally { UIGraphics.EndImageContext(); } }