Thank you for your answer. This part (calling js from java) is working fine. But my problem is calling generated javascript from hand written javascript... The export trick (see MyUtilityClass) does not seem to expose javamethods to hand written javascript.
How can I call my java code from je javascript ? I have read the syntax in the dev guide with @package.className::methodeName(parameters) but could not make it work. I could neither make the export thing work... I miss something but I cannot see where... 2010/10/6 Y2i <yur...@gmail.com> > I think Boris is correct by using $wnd. I also call my javascript > library functions from a native method through $wnd, as described > here: > http://googlewebtoolkit.blogspot.com/2008/07/getting-to-really-know-gwt-part-1-jsni.html > > Boris' example seems complicated. At the beginning I would simply > create a javascript function that calls alert: > > function sayHello(name) { > alert("Hello from JavaScript, " + name); > } > > and a native method in my Entry Point class: > > native void sayHelloInJava(String name) /*-{ > $wnd.sayHello(name); > }-*/; > > (this is exactly as shown in the reference above) > > I use exactly the same approach, except instead of using HTML file I > place my JS library into a public folder and use <script src='lib.js'/ > > in my module. > This technique is described here: > > http://code.google.com/webtoolkit/doc/latest/DevGuideOrganizingProjects.html#DevGuideModules > > Once this worked I would move further. > > > > On Oct 5, 2:33 pm, Daniel Kurka <kurka.dan...@googlemail.com> wrote: > > if you are in javascript its not $wnd its just window :) > > > > 2010/10/5 Boris Lenzinger <boris.lenzin...@gmail.com> > > > > > > > > > Sorry for the javascript : there is a mistake : variable name is not > > > buttonnode but button at return step of the method... > > > Anyway the problem still stands ;-) > > > > > Boris > > > > > 2010/10/5 Boris Lenzinger <boris.lenzin...@gmail.com> > > > > >> Hi, > > > > >> I'm currently trying to call a "java" method from a javascript that > lives > > >> outside of the generated javascript from GWT. > > > > >> What I want to do is the following : > > >> make the gwt component communicates with a javascript component (in > both > > >> ways). > > >> I have to say that I don't know at all javascript...... > > > > >> The problem I encounter is the following : > > >> * call to javascript method (generated by GWT) from my handwritten > > >> javascript does not work : firebug says : $wnd does not exist. > > >> I thought this variable was always existing in javascript but this > > >> assumption is may be false. > > > > >> I think it is quite basic (probably a problem of understanding in > > >> javascript). I have read the following (this is where I found most of > the > > >> code for doing the stuff) : > > > > >>http://www.gwtapps.com/doc/html/com.google.gwt.doc.DeveloperGuide.Jav. > .. > > >> plus others (like > > >> > http://www.mail-archive.com/google-web-toolkit@googlegroups.com/msg38...) > but I'm stuck there. > > > > >> Here the very basic code to test the feature : > > > > >> ============================ > > >> The GWT Component > > >> ============================ > > >> package test.app.client; > > > > >> import com.google.gwt.core.client.EntryPoint; > > >> import com.google.gwt.dom.client.DivElement; > > >> import com.google.gwt.dom.client.Document; > > >> import com.google.gwt.event.dom.client.ClickEvent; > > >> import com.google.gwt.event.dom.client.ClickHandler; > > >> import com.google.gwt.user.client.ui.Button; > > >> import com.google.gwt.user.client.ui.DialogBox; > > >> import com.google.gwt.user.client.ui.HTML; > > >> import com.google.gwt.user.client.ui.RootPanel; > > >> import com.google.gwt.user.client.ui.VerticalPanel; > > >> import com.google.gwt.user.client.ui.Widget; > > > > >> /** > > >> * Entry point classes define <code>onModuleLoad()</code>. > > >> */ > > >> public class GwtAndJavascript implements EntryPoint { > > > > >> JsButton jsButton; > > > > >> public void onModuleLoad() { > > >> final Button gwtButton = new Button("Add item to JS !"); > > > > >> final VerticalPanel panel = new VerticalPanel(); > > >> panel.add(gwtButton); > > > > >> RootPanel.get("sendButtonContainer").add(panel); > > >> MyUtilityClass.exportStaticMethod(); > > > > >> final ClickHandler handler = new ClickHandler() { > > > > >> public void onClick(ClickEvent event) { > > >> jsButton.callSayHello("User"); > > >> } > > >> }; > > >> gwtButton.addClickHandler(handler); > > > > >> // Now I want to add javascript button that lives in a js > script... > > >> jsButton = new JsButton(); > > >> panel.add(jsButton); > > > > >> } > > > > >> private class JsButton extends Widget { > > > > >> public JsButton() { > > >> DivElement element = Document.get().createDivElement(); > > >> makeMyGraphicalObject(element); > > >> setElement(element); > > >> } > > > > >> private native void makeMyGraphicalObject(DivElement element) /*-{ > > >> $wnd.createButton(element); > > >> }-*/; > > > > >> public native void callSayHello(String name) /*-{ > > >> $wnd.javascriptSayHello(name); > > >> }-*/; > > > > >> } > > > > >> } > > > > >> ======================= > > >> The class that should help to trigger the java method from javascript > > >> ======================= > > >> package test.app.client; > > > > >> import com.google.gwt.user.client.Window; > > > > >> public class MyUtilityClass { > > > > >> public static void sayHello() { > > >> Window.alert("Say Hello !"); > > >> } > > > > >> public static native void exportStaticMethod() /*-{ > > >> $wnd.sayHello = @test.app.client.MyUtilityClass::sayHello(); > > >> }-*/; > > > > >> } > > > > >> ==================== > > >> The HTML page > > >> ==================== > > > > >> <html> > > >> <head> > > >> <meta http-equiv="content-type" content="text/html; > charset=UTF-8"> > > > > >> <!-- > --> > > >> <!-- Consider inlining CSS to reduce the number of requested files > --> > > >> <!-- > --> > > >> <link type="text/css" rel="stylesheet" > href="GwtAndJavascript.css"> > > > > >> <!-- --> > > >> <!-- Any title is fine --> > > >> <!-- --> > > >> <title>Web Application Starter Project</title> > > > > >> <!-- --> > > >> <!-- This script loads your compiled module. --> > > >> <!-- If you add any GWT meta tags, they must --> > > >> <!-- be added before this line. --> > > >> <!-- --> > > >> <script type="text/javascript" language="javascript" > > >> src="gwtandjavascript/gwtandjavascript.nocache.js"></script> > > >> <script type="text/javascript" language="javascript" > > >> src="button.js"></script> > > >> </head> > > > > >> <!-- --> > > >> <!-- The body can have arbitrary html, or --> > > >> <!-- you can leave the body empty if you want --> > > >> <!-- to create a completely dynamic UI. --> > > >> <!-- --> > > >> <body> > > > > >> <!-- OPTIONAL: include this if you want history support --> > > >> <iframe src="javascript:''" id="__gwt_historyFrame" tabIndex='-1' > > >> style="position:absolute;width:0;height:0;border:0"></iframe> > > > > >> <!-- RECOMMENDED if your web app will not function without > JavaScript > > >> enabled --> > > >> <noscript> > > >> <div style="width: 22em; position: absolute; left: 50%; > margin-left: > > >> -11em; color: red; background-color: white; border: 1px solid red; > padding: > > >> 4px; font-family: sans-serif"> > > >> Your web browser must have JavaScript enabled > > >> in order for this application to display correctly. > > >> </div> > > >> </noscript> > > > > >> <table align="center"> > > >> <tr> > > >> <td id="sendButtonContainer"></td> > > >> </tr> > > >> <tr> > > >> <td colspan="2" style="color:red;" > id="errorLabelContainer"></td> > > >> </tr> > > >> </table> > > >> </body> > > >> </html> > > > > >> ==================== > > >> The javascript code > > >> ==================== > > > > >> function createButton(divElement) { > > >> var button= document.createElement('input'); > > >> button.setAttribute('type','button'); > > >> button.setAttribute('name','button'); > > >> button.setAttribute('value','JS Button'); > > >> divElement.appendChild(button); > > >> button.onclick = function() { $wnd.sayHello; }; > > > > >> return button; > > > > >> } > > > > >> // This is called from java > > >> function javascriptSayHello(name) { > > >> alert("Hello " + name); > > >> } > > > > >> ============ > > > > >> Any help would be highly appreciated :-) > > > > >> thanks in advance > > > > >> Boris > > > > > -- > > > You received this message because you are subscribed to the Google > Groups > > > "Google Web Toolkit" group. > > > To post to this group, send email to > google-web-tool...@googlegroups.com. > > > To unsubscribe from this group, send email to > > > google-web-toolkit+unsubscr...@googlegroups.com<google-web-toolkit%2bunsubscr...@googlegroups.com><google-web-toolkit%2Bunsubs > cr...@googlegroups.com> > > > . > > > 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 google-web-tool...@googlegroups.com. > To unsubscribe from this group, send email to > google-web-toolkit+unsubscr...@googlegroups.com<google-web-toolkit%2bunsubscr...@googlegroups.com> > . > 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. 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