My main problem is, that i can not send the svg text to the resource. Doing so by request parameters is not an option because the firewall will deny that long cryptic content. Therefor i would like to send the svg content through a form.
So far i have the following: In my page-markup (containing the svg) i have <form method="POST" wicket:id="svgForm" onSubmit="getSvg(this)"> <input type="hidden" value="" wicket:id="svg-data" name="data" /> <input id="chart-export" type="submit" class="button secondary" wicket:message="value:misc.chartExport" /> </form> <script type="text/javascript"> var getSvg = function(element) { var svgHtml = document.querySelector('#chart-container .highcharts-container').innerHTML; element.querySelector('input[name="data"]').value = svgHtml; } </script> In my page i have add( new WebMarkupContainer("svgForm") .add(AttributeModifier.replace("action", PngResourceReference.url().toString()))); I've registered a resource by reference app.mountResource("/svg2png", new PngResourceReference()); ----------- public class PngResourceReference extends ResourceReference { private static final Key KEY = new Key(PngResourceReference.class.getName(), "svg-to-png", null, null, null); public PngResourceReference() { super(KEY); } @Override public IResource getResource() { return new PngResource(); } public static CharSequence url() { PageParameters svgParameters = new PageParameters(); return RequestCycle.get().urlFor(Application.get().getResourceReferenceRegistry().getResourceReference(KEY, false, false), svgParameters); } } public class PngResource extends ByteArrayResource { public PngResource() { super("image/png"); } @Override protected void configureResponse(ResourceResponse response, Attributes attributes) { super.configureResponse(response, attributes); response.setContentDisposition(ContentDisposition.ATTACHMENT); response.setFileName("chart.png"); response.disableCaching(); } @Override protected byte[] getData(Attributes attributes) { ByteArrayOutputStream os; try { PNGTranscoder t = new PNGTranscoder(); // Set the transcoder input and output. String svg = "something"; TranscoderInput input = new TranscoderInput(new StringReader(svg)); os = new ByteArrayOutputStream(); TranscoderOutput output = new TranscoderOutput(os); // Perform the transcoding. t.transcode(input, output); os.close(); } catch (TranscoderException | IOException e) { throw new RuntimeException(e); } return os.toByteArray(); } } > Gesendet: Montag, 17. Juli 2017 um 15:30 Uhr > Von: "Martin Grigorov" <mgrigo...@apache.org> > An: "users@wicket.apache.org" <users@wicket.apache.org> > Betreff: Re: Re: Use Resource to transfer SVG to PNG > > On Mon, Jul 17, 2017 at 3:13 PM, Per Newgro <per.new...@gmx.ch> wrote: > > > Thanks for your response Martin. > > > > I tried to make it work the whole day now. But i can not get it to work > > with IE11. > > There is always a security error. This is a known problem for IE and > > canvas. > > > > I ended up: > > > > $("#chart-export").on("click", function() { > > var svg = document.querySelector( "svg" ); > > var svgData = new XMLSerializer().serializeToString( svg ); > > > > var canvas = document.createElement( "canvas" ); > > document.body.appendChild(canvas); > > var svgSize = svg.getBoundingClientRect(); > > canvas.width = svgSize.width; > > canvas.height = svgSize.height; > > > > var ctx = canvas.getContext( "2d" ); > > ctx.clearRect(0, 0, canvas.width, canvas.height); > > > > var img = document.createElement("img"); > > img.setAttribute("crossOrigin", "anonymous"); > > img.onload = function() { > > ctx.drawImage( img, 0, 0 ); > > var a = document.createElement("a"); > > a.download = "chart.png"; > > a.href = canvas.toDataURL( "image/png" ); > > document.body.appendChild(a); > > a.click(); > > }; > > img.setAttribute("src", "data:image/svg+xml;base64," + > > btoa(unescape(encodeURIComponent(svgData))) > > ); > > }); > > > > So i need to go on the other way. But there my problems still occur. > > > > What exactly are the problems ? > It is not very clear from your first email. > > > > > > Regards > > Per > > > > > Gesendet: Montag, 17. Juli 2017 um 10:42 Uhr > > > Von: "Martin Grigorov" <mgrigo...@apache.org> > > > An: "users@wicket.apache.org" <users@wicket.apache.org> > > > Betreff: Re: Use Resource to transfer SVG to PNG > > > > > > Hi, > > > > > > Wouldn't HTML Canvas API be better solution? > > > See https://stackoverflow.com/a/27232525/497381 > > > > > > > > > Martin Grigorov > > > Wicket Training and Consulting > > > https://twitter.com/mtgrigorov > > > > > > On Mon, Jul 17, 2017 at 10:12 AM, Per Newgro <per.new...@gmx.ch> wrote: > > > > > > > Hello *, > > > > > > > > I would like to generate a png from a svg. The transcoding is done by > > > > using Batik. > > > > So far it works as expected. > > > > > > > > But i'm not sure how to provide the resulting png (a byte[]) to my > > > > frontend. > > > > > > > > The svg is generate in browser by using highcharts. I would like to > > > > provide a button > > > > that downloads the transcoded png by sending a request to the > > "transcoding > > > > resource" > > > > and using the svg-dom from browser. > > > > > > > > Is there someone who did that already once? Can you please give me a > > hint > > > > how this could work? > > > > > > > > Thanks for your support > > > > Per > > > > > > > > --------------------------------------------------------------------- > > > > To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > > > > For additional commands, e-mail: users-h...@wicket.apache.org > > > > > > > > > > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > > For additional commands, e-mail: users-h...@wicket.apache.org > > > > > --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org For additional commands, e-mail: users-h...@wicket.apache.org