Possible to make a screenshot programmatically? - Page 2

filharvey · 10-08-2008, 07:25 PM

k, I'm trying the code suggested on a eaglView, but only getting a white image.

Quote:

CGRect screenRect = [[UIScreen mainScreen] bounds];
UIGraphicsBeginImageContext(screenRect.size);

CGContextRef ctx = UIGraphicsGetCurrentContext();
[glView.layer renderInContext:ctx];

UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

UIImageWriteToSavedPhotosAlbum(viewImage, self, nil, nil);

So it saves an image, but the image is just white, not the opengl scene I've rendered.

Thanks in advance for any help.

Phil

fladnag · 10-12-2008, 06:18 PM

I am all of a sudden getting the same problem as filharvey is. The code worked for a few days then suddenly stopped working.
I've tried two variations of the script as below and they both have the same results - "taking" a screen shot but adding only a white image to the photo library. Anyone have a guess as to what is going on?

Code:

//THIS WORKED THEN STOPPED WORKING
		UIGraphicsBeginImageContext(self.window.bounds.size);
		[self.window.layer renderInContext:UIGraphicsGetCurrentContext()];
		UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
		UIGraphicsEndImageContext();
		UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);

		//THIS IS NOT WORKING EITHER
		CGRect screenRect = [[UIScreen mainScreen] bounds];
		UIGraphicsBeginImageContext(screenRect.size);
		
		CGContextRef ctx = UIGraphicsGetCurrentContext();
		[[UIColor blackColor] set];
		CGContextFillRect(ctx, screenRect);
		
		[self.window.layer renderInContext:ctx];
		
		UIImage *screenImage = UIGraphicsGetImageFromCurrentImageContext();
		UIImageWriteToSavedPhotosAlbum(screenImage, nil, nil, nil);
		UIGraphicsEndImageContext();

Deklann · 10-12-2008, 09:41 PM

NEVERMIND

I originally had posted how to do a screen shot here, but then I saw that the poster knows how it's done - but wants to do it through code.

For some reason, it wont let me delete this post - so instead you're stuck reading garbage... sorry

MaCeXpErTo · 01-24-2009, 01:37 AM

Quote:

Originally Posted by fladnag

I am all of a sudden getting the same problem as filharvey is. The code worked for a few days then suddenly stopped working.
I've tried two variations of the script as below and they both have the same results - "taking" a screen shot but adding only a white image to the photo library. Anyone have a guess as to what is going on?

Code:

//THIS WORKED THEN STOPPED WORKING
		UIGraphicsBeginImageContext(self.window.bounds.size);
		[self.window.layer renderInContext:UIGraphicsGetCurrentContext()];
		UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
		UIGraphicsEndImageContext();
		UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);

		//THIS IS NOT WORKING EITHER
		CGRect screenRect = [[UIScreen mainScreen] bounds];
		UIGraphicsBeginImageContext(screenRect.size);
		
		CGContextRef ctx = UIGraphicsGetCurrentContext();
		[[UIColor blackColor] set];
		CGContextFillRect(ctx, screenRect);
		
		[self.window.layer renderInContext:ctx];
		
		UIImage *screenImage = UIGraphicsGetImageFromCurrentImageContext();
		UIImageWriteToSavedPhotosAlbum(screenImage, nil, nil, nil);
		UIGraphicsEndImageContext();

Did you ever fix it?

RickMaddy · 01-24-2009, 01:42 AM

Search here for 'renderInContext'. There are several examples of rendering views to an image.

MaCeXpErTo · 01-24-2009, 01:47 AM

Quote:

Originally Posted by RickMaddy

Search here for 'renderInContext'. There are several examples of rendering views to an image.

Thanks Rick!

Dmoney · 03-05-2009, 03:33 AM

I'm using this code to save my screen shot and its working:

Code:

	UIGraphicsBeginImageContext(Background.bounds.size);
	[Background.window.layer renderInContext:UIGraphicsGetCurrentContext()];
	UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
	UIGraphicsEndImageContext();
	
	UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);

It works but I'm getting warnings now:

warning: no '-renderInContext:' method found
warning: (Messages without a matching method signature
warning: incomplete implementation of class 'VCMenu'
warning: method definition for '-renderInContext' not found

Hilton · 03-05-2009, 04:25 AM

There are three applications that can be directly invoked (by just executing the program to take a screenshot, which can also be easily checked if you configure your Pocket PC to invoke the application straight from the Settings/Button applet or just click its icon in Start/Programs) and, therefore, be periodically run: PQV (for Portrait-only or game screenshot taking, strictly on QVGA devices), WebIS Inc.

macounette · 04-04-2009, 02:57 PM

Is it possible to do homescreen screenshot with this code ?
I am trying to access to the homescreen view, but it doesn't work...

cclaan · 04-11-2009, 03:31 PM

Quote:

Originally Posted by Dmoney

I'm using this code to save my screen shot and its working:

Code:

	UIGraphicsBeginImageContext(Background.bounds.size);
	[Background.window.layer renderInContext:UIGraphicsGetCurrentContext()];
	UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
	UIGraphicsEndImageContext();
	
	UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);

It works but I'm getting warnings now:

warning: no '-renderInContext:' method found
warning: (Messages without a matching method signature
warning: incomplete implementation of class 'VCMenu'
warning: method definition for '-renderInContext' not found

you need to import the Quartz framework into your app, then include the header:

Code:

#include <QuartzCore/QuartzCore.h>

starfall · 07-28-2009, 05:38 PM

Quote:

Originally Posted by cclaan

you need to import the Quartz framework into your app, then include the header:

Code:

#include <QuartzCore/QuartzCore.h>

Thanks for the tip. I have been trying to do a screenshot. It turns out to be so easy now.

hicatchme · 09-07-2009, 07:56 AM

Quote:

Originally Posted by NewiPhoneDeveloper

Would you happen to have an example of that emailing procedure?

Many thanks!

You can attach the file to the mail. It only supports iPhone OS 3.0 later.

vikysaran · 10-03-2009, 05:04 AM

Quote:

Originally Posted by cclaan

you need to import the Quartz framework into your app, then include the header:

Code:

#include <QuartzCore/QuartzCore.h>

its still showing 'Background Undecleared (first use of this function)'

vikysaran · 10-03-2009, 05:23 AM

Quote:

Originally Posted by fladnag

I am all of a sudden getting the same problem as filharvey is. The code worked for a few days then suddenly stopped working.
I've tried two variations of the script as below and they both have the same results - "taking" a screen shot but adding only a white image to the photo library. Anyone have a guess as to what is going on?

Code:

//THIS WORKED THEN STOPPED WORKING
		UIGraphicsBeginImageContext(self.window.bounds.size);
		[self.window.layer renderInContext:UIGraphicsGetCurrentContext()];
		UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
		UIGraphicsEndImageContext();
		UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);

		//THIS IS NOT WORKING EITHER
		CGRect screenRect = [[UIScreen mainScreen] bounds];
		UIGraphicsBeginImageContext(screenRect.size);
		
		CGContextRef ctx = UIGraphicsGetCurrentContext();
		[[UIColor blackColor] set];
		CGContextFillRect(ctx, screenRect);
		
		[self.window.layer renderInContext:ctx];
		
		UIImage *screenImage = UIGraphicsGetImageFromCurrentImageContext();
		UIImageWriteToSavedPhotosAlbum(screenImage, nil, nil, nil);
		UIGraphicsEndImageContext();

i made a little modification and it is working here

Code:

	CGRect contextRect  = CGRectMake(50, 50, 200, 200);// whatever you need
	UIGraphicsBeginImageContext(contextRect.size);	

	[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
	UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
	UIGraphicsEndImageContext();
	UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);

But the resulting image is starting from origin (0,0) of screen whether I'm giving anything for x and y. But height and width are working as defined.
thanx for the code anyway...

vikysaran · 10-07-2009, 03:34 AM

refer http://www.iphonedevsdk.com/forum/ip...rge-issue.html

and http://www.iphonedevsdk.com/forum/ip...re-iphone.html

hope it helps

peterj · 11-15-2010, 05:58 AM

Quote:

Originally Posted by vikysaran

i made a little modification and it is working here

Code:

	CGRect contextRect  = CGRectMake(50, 50, 200, 200);// whatever you need
	UIGraphicsBeginImageContext(contextRect.size);	

	[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
	UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
	UIGraphicsEndImageContext();
	UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);

But the resulting image is starting from origin (0,0) of screen whether I'm giving anything for x and y. But height and width are working as defined.
thanx for the code anyway...

Did you find a solution about the problem it was starting at 0,0 ? I am looking for the same...