Sending Javascript to GWT JSNI

I know how to call Javascript from GWT.But I have a javascript function that returns a string so, how could I when that function is called 开发者_开发技巧send it to GWT.

Hope this makes sense

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This is how you collect strings from JSNI fn

public static native String stringExample() /*-{ return "String1"; }-*/;

This is how you pass a string to JSNI fn

public static native void alert(String msg) /*-{ $wnd.alert(msg); }-*/;

Hope this is what you were looking for.