Hi Moa-Code, As you can see by scanning GWT widget library, you won't find a component "ready to use" doing what you want.
But, there is a solution provided by HTML5 canvas element. 1) in GWT designer, choose an HTMLPanel as container. 2) in this container, embed a web page with <!DOCTYPE html> ( standard mode HTML5 for recent browser) 3) in this HTML page insert this : <canvas id="myCanvas" width="400" height="400"></canvas> 4) with javascript, create an image : var myImgToProcess = new Image(); myImgToProcess.src='url of your img'; 5) put the image on the canvas ( see canvas specification<http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html>) : - get the graphic context of the canvas to draw your image - with javascript mouse event handler, allow your end-user to draw cercle etc..on your image - serialize ( save) in a javascript integer array, the strokes that user is drawing 6) send an AJAX request to the server, send the array of strokes in a POST HTTP That's all. Remember that GWT is a framework, allowing you to developp a Ajax web application using java langage in a friendly way. Your code is translated in optimized javascript. But HTML is still omnipresent, and you can still use it. I hope it helps. Regards. Karim Duran. 2011/8/7 moa-code <[email protected]> > Hi, > > I want a component that I can use to allow a user to draw a box or > circle over an image they have previously uploaded. I then want the > component to message the circle or squares dimensions back to the > server, so the server can either perform a crop on image to the size > of the square, or perform some other image manipulation on the area > where the circle was. > > I do not want to have to use Flash or Java Applet for this, as I would > really want this to work without Java installed and on machines > without flash. > > Is GWT able to do this sort of thing? > > Any pointers or example would be most appreciated as I am totally new > to GWT. > > Thanks. > > -- > You received this message because you are subscribed to the Google Groups > "Google Web Toolkit" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/google-web-toolkit?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-web-toolkit?hl=en.
