Is there any way to Convert NSView Contain Subviews into NSImage?

Question

Is there any way to Convert NSView Contain many Subviews with background color into NSImage ? Sample code will be great

    NSBitmapImageRep *rep = [[NSBitmapImageRep alloc] initWithFocusedViewRect:[_collageView bounds]];
        [_collageView unlockFocus];
    //    NSData *exportedData = [rep representationUsingType:NSJPEGFileType properties:nil];
          NSData *exportedData = [rep representationUsingType:NSPNGFileType properties:nil];


        NSSavePanel *savepanel = [NSSavePanel savePanel];
    savepanel.title = @"Save chart";
    [savepanel setAllowedFileTypes:[NSArray arrayWithObject:@"png"]];
    [savepanel beginSheetModalForWindow:self.view.window completionHandler:^(NSInteger result)
     {
         if (NSFileHandlingPanelOKButton == result)
         {
             NSURL* fileURL = [savepanel URL];
             if ([fileURL.pathExtension isEqualToString:@""])
                 fileURL = [fileURL URLByAppendingPathExtension:@"png"];

             [exportedData writeToURL:fileURL atomically:YES];
         }
     }];

i also used the following code to

 [_collageView lockFocus];
    NSBitmapImageRep *bits = [[NSBitmapImageRep alloc]initWithFocusedViewRect: [_collageView bounds]];
    [_collageView unlockFocus];
    NSImage *image1 = [[NSImage alloc] init];
    [image1 addRepresentation: bits];
    [self.ImageView setImage:image1];

but not working

Answer 1

I am able to solve my problem with the following Code

  // Setup the image to render
        NSRect imgRect = _collageView.frame;
        NSSize imgSize = imgRect.size;

        NSBitmapImageRep *rep = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL
                                                                        pixelsWide:imgSize.width
                                                                        pixelsHigh:imgSize.height
                                                                     bitsPerSample:8
                                                                   samplesPerPixel:4
                                                                          hasAlpha:YES
                                                                          isPlanar:NO
                                                                    colorSpaceName:NSDeviceRGBColorSpace
                                                                      bitmapFormat:NSAlphaFirstBitmapFormat
                                                                       bytesPerRow:0
                                                                      bitsPerPixel:0];

        NSGraphicsContext *context = [NSGraphicsContext graphicsContextWithBitmapImageRep:rep];
        [NSGraphicsContext saveGraphicsState];
        [NSGraphicsContext setCurrentContext:context];
        // Render
        CGContextRef zCgContextRef = (CGContextRef) [context graphicsPort];
        [[_collageView layer] renderInContext:zCgContextRef];

        // Get the Data for the image
        NSData *exportedData = [rep representationUsingType:NSJPEGFileType properties:nil];


        // Start the savepanel
        NSSavePanel *savepanel = [NSSavePanel savePanel];
        savepanel.title = @"Save chart";

        [savepanel setAllowedFileTypes:[NSArray arrayWithObject:@"jpg"]];
        [savepanel beginSheetModalForWindow:self.view.window completionHandler:^(NSInteger result)
         {
             if (NSFileHandlingPanelOKButton == result)
             {
                 NSURL* fileURL = [savepanel URL];

                 if ([fileURL.pathExtension isEqualToString:@""])
                     fileURL = [fileURL URLByAppendingPathExtension:@"jpg"];

                 [exportedData writeToURL:fileURL atomically:YES];
             }
         }];