I'm trying to get an image of the contents of a UITextView, including the part that is not currently visible on the screen. I do it exactly as pointed out in the first answer here:
Getting a screenshot of a UIScrollView, including offscreen parts, except for using a UITextView instead of a UIScrollView. Unfortunately, no matter what changes I do to the code, I'm always only getting a part of my UITextView, which is about 1024x315 (I test it on the iPad simulator, in landscape orientation). Why is the size so weird and how can I make it as I want to?
That's how I'm saving the image (ResultsView is an instance of UITextView):
UIImage* image = nil;
UIGraphicsBeginImageContext(ResultsView.contentSize);
CGPoint savedContentOffset = ResultsView.contentOffset;
CGRect savedFrame = ResultsView.frame;
ResultsView.contentOffset = CGPointZero;
ResultsView.frame = CGRectMake(0, 0, ResultsView.contentSize.width, ResultsView.contentSize.height);
[ResultsView.layer renderInContext: UIGraphicsGetCurrentContext()];
image = UIGraphicsGetImageFromCurrentImageContext();
ResultsView.contentOffset = savedContentOffset;
ResultsView.frame = savedFrame;
UIGraphicsEndImageContext();
NSData * data = UIImagePNGRepresentation(image);
UIImageWriteToSavedPhotosAlbum([UIImage imageWithData:data], nil, nil, nil);
Related
Am making an iOS application which captures screenshot of a textview filled with some image. The problem is that the screen shot captures the entire screen.
How do I take screen shot of UITextView using Swift?
The following worked for me
UIGraphicsBeginImageContextWithOptions(self.textField.bounds.size, false, 0);
self.textField.drawViewHierarchyInRect(self.textField.bounds, afterScreenUpdates: true)
let copied = UIGraphicsGetImageFromCurrentImageContext();
imageView.image = copied
UIGraphicsEndImageContext();
You can save any view as image by using drawViewHierarchyInRect method
UIGraphicsBeginImageContextWithOptions(self.textView.bounds.size, false, 0);
self.textText.drawViewHierarchyInRect(CGRectMake(0, 0, self.textView.frame.size.width, self.textView.frame.size.height),afterScreenUpdates:true)
var screenShot:UIImage = UIGraphicsGetImageFromCurrentImageContext();
All answers are good but missing is scale which is necessary in context.
Use UIView's drawViewHierarchyInRect mehtod to capture screen.
//Use screen scale for better images
let screenScale = UIScreen.mainScreen().scale;
//create context
UIGraphicsBeginImageContextWithOptions(yourView.bounds.size, false, screenScale);
//use view for drawing
yourView.drawViewHierarchyInRect(yourView.bounds, afterScreenUpdates: true)
//get captured image
let capturedImage = UIGraphicsGetImageFromCurrentImageContext();
//last dump context
UIGraphicsEndImageContext();
Another sloution : use UIView's layer's renderInContext
//Use screen scale for better images
let screenScale = UIScreen.mainScreen().scale;
//create context
UIGraphicsBeginImageContextWithOptions(yourView.bounds.size, false, screenScale);
//use view for drawing
yourView.layer.renderInContext(UIGraphicsGetCurrentContext())
//get captured image
let capturedImage = UIGraphicsGetImageFromCurrentImageContext();
//last dump context
UIGraphicsEndImageContext();
I am able to save the contents of a UIView as an image to the library.
The image i am trying to save is very a good resolution on the app, but saving it to the photo library reduces the resolution significantly. The image i am trying to save, is of the same width as the screen but many times the height of the screen.
The image i save looks like how i want on the UIScrollView in the app but the image it saves has a lower resolution than the actual image. How can i prevent it from doing this?
Thanks in advanced :D
edit: adding the code...
- (void) saveImageToLibrary
{
UIImage* image;// = nil;
UIGraphicsBeginImageContext(scrollview.contentSize);
{
CGPoint savedContentOffset = scrollview.contentOffset;
CGRect savedFrame = scrollview.frame;
scrollview.contentOffset = CGPointZero;
scrollview.frame = CGRectMake(0, 0, scrollview.contentSize.width, scrollview.contentSize.height);
self.view.frame = CGRectMake(0, 0, scrollview.contentSize.width, scrollview.contentSize.height);
[scrollview.layer renderInContext: UIGraphicsGetCurrentContext()];
image = UIGraphicsGetImageFromCurrentImageContext();
scrollview.contentOffset = savedContentOffset;
scrollview.frame = savedFrame;
self.view.frame = savedFrame;
}
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(image, nil,nil,nil);
}
i hope this is helpful.
Are you setting the correct scale when you try to create the image? Could you post the code?
OK guys and goyals... i think i figured out the problem.
the issue is the iPhone simulator. depending on the hardware you are sumulating, image will be optimised for the resolution of the sumilator.
im not entirely conviced by this because i was previously simulating an iPhone 5 (which has retina display), but simulating iphone 6 seems to work fine.
here is a link if you want to follow further details or if you want to add to this thread :D
https://stackoverflow.com/questions/8032528/uiimage-image-loaded-from-appbundle-is-saved-at-lower-resolution-in-app-direct
Use this instead:
UIGraphicsBeginImageContextWithOptions(scrollView.contentSize, scrollView.opaque, [[UIScreen mainScreen] scale]);
EDIT
You can also try setting the scale to zero:
UIGraphicsBeginImageContextWithOptions(scrollView.contentSize, scrollView.opaque, 0.0);
Does that help you?
I am working on iOS application where I need to capture the view and send MMS to particular person.Its all working fine.But I am facing problem to capture which is not visible (For more clarification I attached image).
I am getting the screen shot of the view which is visible.How to solve the problem? Is there any approach to reach my requirement? The image what I am getting is
I used the code to take screenshot is
UIGraphicsBeginImageContext(webview_pdf.bounds.size);
[webview_pdf.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *pdfImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Good suggestions are appreciable.Thanks in advance.!
Finally found the solution to this
+ (UIImage *) imageFromWebView:(UIWebView *)view
{
// tempframe to reset view size after image was created
CGRect tmpFrame = view.frame;
// set new Frame
CGRect aFrame = view.frame;
aFrame.size.height = [view sizeThatFits:[[UIScreen mainScreen] bounds].size].height;
view.frame = aFrame;
// do image magic
UIGraphicsBeginImageContext([view sizeThatFits:[[UIScreen mainScreen] bounds].size]);
CGContextRef resizedContext = UIGraphicsGetCurrentContext();
[view.layer renderInContext:resizedContext];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
// reset Frame of view to origin
view.frame = tmpFrame;
return image;
}
You need to create another view that is the full size of the content. You can add this view off screen and then capture it the same way as you have done here. The reason it is cut off is because the view has only rendered that part of the content.
I am making application related to images. I have multiple images on my screen. I had take screen shot of that. But it should not provide my whole screen.
Little part of the top most & bottom most part need not be shown in that.
I have navigation bar on top. And some buttons at bottom. I don't want to capture that buttons and navigation bar in my screenshot image.
Below is my code for screen shot.
-(UIImage *) screenshot
{
UIGraphicsBeginImageContextWithOptions(self.view.bounds.size, YES, [UIScreen mainScreen].scale);
[self.view drawViewHierarchyInRect:self.view.frame afterScreenUpdates:YES];
image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
After taking screenshot I am using it by below code in facebook share method,
UIImage *image12 =[self screenshot];
[mySLComposerSheet addImage:image12];
the easiest way to achieve this would be to add a UIView which holds all the content you want to take a screenshot of and then call drawViewHierarchyInRect from that UIView instead of the main UIView.
Something like this:
-(UIImage *) screenshot {
UIGraphicsBeginImageContextWithOptions(contentView.bounds.size, YES, [UIScreen mainScreen].scale);
[contentView drawViewHierarchyInRect:contentView.frame afterScreenUpdates:YES];
image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
Hope this helps!
You can use my below code to take screen shot of a view.
I have put the condition to check the size of a screenshot.
With this code image is saved in your documents folder and from there you can use your image to share on Facebook or anywhere you want to share.
CGSize size = self.view.bounds.size;
CGRect cropRect;
if ([self isPad])
{
cropRect = CGRectMake(110 , 70 , 300 , 300);
}
else
{
if (IS_IPHONE_5)
{
cropRect = CGRectMake(55 , 25 , 173 , 152);
}
else
{
cropRect = CGRectMake(30 , 25 , 164 , 141);
}
}
/* Get the entire on screen map as Image */
UIGraphicsBeginImageContext(size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage * mapImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
/* Crop the desired region */
CGImageRef imageRef = CGImageCreateWithImageInRect(mapImage.CGImage, cropRect);
UIImage * cropImage = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
/* Save the cropped image
UIImageWriteToSavedPhotosAlbum(cropImage, nil, nil, nil);*/
//save to document folder
NSData * imageData = UIImageJPEGRepresentation(cropImage, 1.0);
NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString* documentsDirectory = [paths objectAtIndex:0];
NSString *imagename=[NSString stringWithFormat:#"Pic.jpg"];
NSString* fullPathToFile = [documentsDirectory stringByAppendingPathComponent:imagename];
////NSLog(#"full path %#",fullPathToFile);
[imageData writeToFile:fullPathToFile atomically:NO];
Hope it helps you.
use this code
-(IBAction)captureScreen:(id)sender
{
UIGraphicsBeginImageContext(webview.frame.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);
}
sample project www.cocoalibrary.blogspot.com
http://www.bobmccune.com/2011/09/08/screen-capture-in-ios-apps/
snapshotViewAfterScreenUpdates
but it is only Available in iOS 7.0 and later.
- (UIView *)snapshotViewAfterScreenUpdates:(BOOL)afterUpdates
This method captures the current visual contents of the screen from the render server and uses them to build a new snapshot view. You can use the returned snapshot view as a visual stand-in for the screen’s contents in your app. For example, you might use a snapshot view to facilitate a full screen animation. Because the content is captured from the already rendered content, this method reflects the current visual appearance of the screen and is not updated to reflect animations that are scheduled or in progress. However, this method is faster than trying to render the contents of the screen into a bitmap image yourself.
https://developer.apple.com/library/ios/documentation/uikit/reference/UIScreen_Class/Reference/UIScreen.html#//apple_ref/occ/instm/UIScreen/snapshotViewAfterScreenUpdates:
I've a UIImageView *userImage whose size is full screen and UIImageView *imageSquare whose size is 320x320. The user will be able to play with userImage to make it bigger, change position, etc. imageSquare is static and should be seen as the cropping view
The code below can crop userImage as the imageSquare.frame.size. My problem is that it crops it from the top of userImage and not from imageSquare.frame.origin, meaning I need to crop it from X and Y coordinates. It's my first time trying to do this and every things I've tried so far can't make it crop from imageSquare.frame.origin.
How could I crop the current view (the one the user is manipulating) of userImage from imageSquare.frame.origin?
CGSize pageSize = imageSquare.frame.size;
UIGraphicsBeginImageContext(pageSize);
CGContextRef resizedContext = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(resizedContext, userImage.frame.origin.x, userImage.frame.origin.y);
[userImage.layer renderInContext:resizedContext];
image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
if (image != nil) {
NSLog(#"is not nil");
NSData *imgData = UIImagePNGRepresentation(image);
imageSquare.image = [[UIImage alloc]initWithData:imgData];
}
You'll need to translate by negative x and y:
CGContextTranslateCTM(resizedContext,
-userImage.frame.origin.x,
-userImage.frame.origin.y);
[userImage.layer renderInContext:resizedContext];