GWT/JS Bridging with JSNI
ahhughes
I'm trying to get a native JS bridge working. For those of you who
don't understand this is providing native JS constructors/functions to
your GWT objects/classes. When trying to access these functions from
js it always says that "Employee is not defined" in the example
below...
Obviously the export() has either not been executed, or there is
something wrong with my JSNI code.
----------------------------------------------------
package jsni.export.test;
public class Employee {
private String name;
public Employee(String name) {
this.name = name;
}
public String getName() {
return name;
}
public static Employee createEmployee(String name) {
return new Employee(name);
}
public native void export() /*-{
$wnd.Employee = function(name) {
// call factory method and store GWT reference
this.instance = @jsni.export.test.Employee::createEmployee(Ljava/
lang/String;)(name);
}
var _= $wnd.Employee.prototype;
_.getNameName = function() {
this.instance.@jsni.export.test.Employee::getName()();
}
}-*/;
}
--------------------------------------
js.....
var employee = new Employee('James Bond');
alert('Welcome '+employee.getName());
---------------
Can anyone confirm:
+ My JSNI/Code above looks ok... particularly..
this.instance = @jsni.export.test.Employee::createEmployee(Ljava/lang/
String;)(name);
+ Do I need to exclusively call Employee.export() from somewhere to
get method this to run? I have tried this, but it still doesn't seem
to matter.
+ Is there a problem with this not being in the *.client.Employee
package? I tried both inside and out without success.
thanks y`all
David Clément
Try to call it from a button, you may have more success.
ahhughes
problem.
is there a way around this... onLoad() could be used on the page?
On Oct 30, 7:10 pm, "David Clément" <dav.clem...@gmail.com> wrote:
> You cannot call it directly in JS, GWT is not loaded when this code is running.
>
> Try to call it from a button, you may have more success.
>
> > this.instan...@jsni.export.test.Employee::getName()();
David Clément
The only solution I have found is to create some "configurations" in
the JS and to retrieve these configurations in the GWT onModuleLoad().
Another option is to add a JSNI method call at the end of your GWT onModuleLoad.
As example a JSNI method like
if($wnd.onGWTLoaded){
$wnd.onGWTLoaded();
}
On 10/30/07, ahhughes <ahhu...@gmail.com> wrote:
>
ahhughes
will pole the exported gwt function until it succeeds.. but yeah, its
dodgy!
var gwtApplication = false;
while(!gwtApplication){
try {
gwtApplication = exportedGWTFunction();
} catch (e){
//pause for a micro second or so...
David Clément
On 10/30/07, ahhughes <ahhu...@gmail.com> wrote:
>
TrashHalo
methods in JS then call it at the end of onModuleLoad
or did I miss something?
David Clément
ahhughes
within the GWT app. I am looking to expose the constructor & methods
of my GWT application to native JS programmers. So the only way I
think this would work would be if I expected the js programmer to
provide a specifically named method to be called from inside the GWT
onLoadModule, or even at the end of the the native export() code....
public native void export() /*-{
$wnd.Employee = function(name) {
// call factory method and store GWT reference
this.instance =
@jsni.export.test.Employee::createEmployee(Ljava/
lang/String;)(name);
}
var _= $wnd.Employee.prototype;
_.getNameName = function() {
this.instan...@jsni.export.test.Employee::getName()();
}
//call the known function the js programmer must
provide
$wnd.initEmployee();
}-*/;
David Clément
GWT is loaded (from user interaction, as example)
On 10/30/07, ahhughes <ahhu...@gmail.com> wrote:
>
ahhughes
On Oct 30, 11:34 pm, "David Clément" <dav.clem...@gmail.com> wrote:
> Yes, that's what you need to do unless these methods are called once
> GWT is loaded (from user interaction, as example)
>
ahhughes
I've this but I just get employee.getName() being 'undefined'....
----HTML/JS----
<html>
......
<button onclick="runJSNI()">Run JSNI</button>
<script type="text/javascript">
runJSNI = function(){
var employee = new Employee('James Bond');
alert('The new employee is: '+employee.getName());
}
</script>
....
</html>
----Export of GWT via JSNI----
package mygwtapp.client;
public class Employee {
private String name;
public Employee(String name) {
this.name = name;
}
public String getName() {
return name;
}
public static Employee createEmployee(String name) {
return new Employee(name);
}
public native void export() /*-{
$wnd.Employee = function(name) {
// call factory method and store GWT reference
this.instance =
@mygwtapp.client.Employee::createEmployee(Ljava/lang/String)(name);
}
var _= $wnd.Employee.prototype;
_.getName = function() {
this.instance.@mygwtappclient.Employee::getName()
();
}
}-*/;
}
----Entry Point that triggers the Empoyee JSNI export()----
package myelders.demand.broadband.client;
import mygwtapp.client.contribute.ContributeWidget;
import com.google.gwt.core.client.EntryPoint;
public class Application implements EntryPoint {
public void onModuleLoad() {
Employee employee = new Employee("BLAH");
employee.export();
}
}
------
My head hurts :'( debugging native JS, calling JSNI, from GWT driven
JS...
stuckagain
Did you get it working yet ? I tried your example code and while the
Javascript does not compile through GWT (some ; missing and such).
Here is code that works for me: (assuming groups does not modify it
like it apparently did to your post). (email me if you need the
working code)
The only thing that will not work is if you try to click the button
before the GWT application is fully loaded. For that you need to call
back into the
HTML/Javascript to signal when the app is ready for action.
Here are my changes:
Export test:
<html>
<head>
<script type="text/javascript" src="mygwtapp.App.nocache.js"></
script>
<title>JSExport test</title>
</head>
<body>
<script type="text/javascript">
runJSNI = function(){
var employee = new Employee('James Bond');
alert('The new employee is:
'+employee.getName());
}
</script>
</body>
</html>
// GWT EntryPoint
public void onModuleLoad() {
}
}
// Employee class
public class Employee {
private final String name;
public Employee(final String name) {
public static native void export() /*-{
$wnd.Employee = function( pName ) {
this.instance = @mygwtapp.client.Employee::createEmployee(Ljava/
lang/String;)(pName);
};
_.getName = function() {
};
}-*/;
public static Employee createEmployee(final String name) {
return new Employee(name);
}
On Oct 31, 12:27 am, ahhughes <ahhug...@gmail.com> wrote:
> Hmmm this still does not work...
>
> I've this but I just get employee.getName() being 'undefined'....
>
> ----HTML/JS----
> <html>
> ......
> <button onclick="runJSNI()">Run JSNI</button>
> <script type="text/javascript">
> runJSNI = function(){
> var employee = new Employee('James Bond');
> alert('The new employee is: '+employee.getName());
> }
>
> </script>
> ....
> </html>
>
>
> public class Employee {
>
> private String name;
>
> public Employee(String name) {
> this.name = name;
> }
>
> public String getName() {
> return name;
> }
>
> public static Employee createEmployee(String name) {
> return new Employee(name);
> }
>
> // call factory method and store GWT reference
> this.instance =
> @mygwtapp.client.Employee::createEmployee(Ljava/lang/String)(name);
>
> }
> var _= $wnd.Employee.prototype;
> _.getName = function() {
> }
> }-*/;
>
> }
>
> ----Entry Point that triggers the Empoyee JSNIexport()----
> package myelders.demand.broadband.client;
>
> import mygwtapp.client.contribute.ContributeWidget;
>
> import com.google.gwt.core.client.EntryPoint;
>
> public class Application implements EntryPoint {
>
> public void onModuleLoad() {
> Employee employee = new Employee("BLAH");
> employee.export();
> }
>
> }
>
> ------
>
> My head hurts :'( debugging nativeJS, calling JSNI, from GWT drivenJS...
>
>
>
>
> > Thanks everyone for your help.
>
> > On Oct 30, 11:34 pm, "David Clément" <dav.clem...@gmail.com> wrote:
>
> > > Yes, that's what you need to do unless these methods are called once
> > > GWT is loaded (from user interaction, as example)
>
> > > On 10/30/07, ahhughes <ahhug...@gmail.com> wrote:
>
> > > > We'll I'm not 100% of how that would work... the onLoadModule() is
> > > > within the GWT app. I am looking to expose the constructor & methods
> > > > think this would work would be if I expected thejsprogrammer to
> > > > onLoadModule, or even at the end of the the nativeexport() code....
>
> > > > // call factory method and store GWT reference
> > > > this.instance =
> > > > @jsni.export.test.Employee::createEmployee(Ljava/
> > > > lang/String;)(name);
>
> > > > }
> > > > var _= $wnd.Employee.prototype;
> > > > _.getNameName = function() {
>
> > > > this.instan...@jsni.export.test.Employee::getName()();
> > > > }
> > > > $wnd.initEmployee();
> > > > }-*/;
>
> > > > }
>
> > > > On Oct 30, 10:49 pm, TrashHalo <TrashH...@gmail.com> wrote:
> > > > > Why not use onModuleLoad? Create a method that forms all your exported
> > > > > or did I miss something?
>
> > > > > On Oct 30, 8:21 am, ahhughes <ahhug...@gmail.com> wrote:
>
> > > > > > dodgy!
>
> > > > > > var gwtApplication = false;
> > > > > > while(!gwtApplication){
> > > > > > try {
> > > > > > gwtApplication = exportedGWTFunction();
> > > > > > } catch (e){
> > > > > > //pause for a micro second or so...
> > > > > > }
>
> > > > > > }
>
> > > > > > On Oct 30, 9:21 pm, "David Cl?ment" <dav.clem...@gmail.com> wrote:
>
> > > > > > > If you find the solution, I would really like to have it.
> > > > > > > The only solution I have found is to create some "configurations" in
> > > > > > > Another option is to add a JSNI method call at the end of your GWT onModuleLoad.
> > > > > > > As example a JSNI method like
> > > > > > > if($wnd.onGWTLoaded){
> > > > > > > $wnd.onGWTLoaded();
>
> > > > > > > }
>
> > > > > > > On 10/30/07, ahhughes <ahhug...@gmail.com> wrote:
>
> > > > > > > > hmmm that is disappointing, but would be a fitting reason for my
> > > > > > > > problem.
>
>
> - Show quoted text -