B4J Code Snippet [B4J] send string msg from WebView js 2 B4J - and from B4J to WebView javascript

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// JSBridge, executejavascript, setBridge(WebEngine we), we.executeScript("window"), class Bridge, javafx.scene.web.WebEngine


B4X:
 '  B4J  !
#Region  Project Attributes
    #MainFormWidth: 600
    #MainFormHeight: 600
#End Region
' wvtest30  js2B4J2js
' https://www.b4x.com/android/forum/threads/making-upcalls-from-javascript-to-javafx.51794/post-771868
' https://www.b4x.com/android/forum/threads/b4j-jscriptengine-jsbridge-js-webviev-to-b4j-to-js-working-example.123516/post-771874
' http://www.mediafire.com/file/q3x4mabuxhp8981/8_B4J2jsBRIDGE.zip/file
' see https://www.b4x.com/android/forum/threads/jscriptengine.35781/
' see https://www.b4x.com/android/forum/threads/making-upcalls-from-javascript-to-javafx.51794/#post-374183

' lib
' JavaObject 2.06, JCore 7.51, jFX 8.30


Sub Process_Globals
    Private fx As JFX
    Private MainForm As Form

    Dim wv As WebView
    Dim we, wvjo As JavaObject

    'wv js to B4J
    Private TextArea1 As TextArea
    Private Button1 As Button
    Public htmname As String = "wv30.html"
End Sub

Sub AppStart (Form1 As Form, Args() As String)
    MainForm = Form1
    MainForm.RootPane.LoadLayout("1") 'Load the layout file.
    MainForm.Show

    we = asJO(wv).RunMethod("getEngine",Null)
    asJO(Me).RunMethod("setBridge",Array(we))

    wv.LoadUrl("file:///../B4X/" & htmname)  'c:/B4X/wv30.html
    Wait For wv_PageFinished (Url As String)
End Sub

Sub asJO(o As JavaObject) As JavaObject
    Return o
End Sub

Sub teststr(s As String)
    Log("teststr " & s)
    TextArea1.Text = s
End Sub

Sub testint(ii As Int)
    Log("testint " & ii)
    TextArea1.Text = ii
End Sub

'B4J2wv
Sub ExecuteJavaScript (wv2 As WebView, script As String) As Object
    Dim jo As JavaObject = wv2
    Return jo.RunMethodJO("getEngine", Null).RunMethod("executeScript", Array(script))
End Sub

Sub Button1_Click
    Dim jstr As String = TextArea1.Text
    jstr = "B4J2wv("""  &  jstr  & """)"
    Log(jstr)
    ExecuteJavaScript(wv, jstr)
End Sub
'B4J2wv end


#if java
import netscape.javascript.JSObject;
import javafx.scene.web.WebEngine;
import java.lang.RuntimeException;
import java.lang.IllegalAccessException;
import java.lang.reflect.InvocationTargetException;

import java.lang.Enum;
import java.lang.reflect.Method;
import javafx.application.Platform;


public static class Bridge{
    public void link(String sub) {
        try{
            Class<?> c = Class.forName("b4j.wvtest21.main");
            final Method m = c.getDeclaredMethod("_" + sub.toLowerCase());
            final Object dummy = null;
            Platform.runLater(new Runnable(){
                public void run(){
                    try{
                        m.invoke(dummy);
                    }catch (IllegalAccessException e){
                        System.out.println(e);
                    }catch (InvocationTargetException ite){
                        System.out.println(ite);
                    }
                }
            });
        } catch (Exception e){
            System.out.println(e);
        }
    }
    public void link2(String sub,Object arg) {   // for call with  1 param
        boolean isInt = false;
        int ti = 0;
        try{
            Class<?> c = Class.forName("b4j.wvtest21.main");
            Class<?> ac = arg.getClass();
            /*
                    Sub Subname(s As String)
                        Log(s)
                    End Sub
              forum change line: Then it will call the sub with an Object parameter is Sub subname(ob As Object)
                Class<?> ac = Object.class;
                    Sub Subname(ob As Object)
                        Log(ob)
                    End Sub
            */
            if (arg instanceof java.lang.Integer){
                ac = int.class;
            }
            final Method m = c.getDeclaredMethod("_" + sub.toLowerCase(),ac);
            final Object dummy = null;
            final Object xarg = arg;
            Platform.runLater(new Runnable(){
                public void run(){
                    try{
                        m.invoke(dummy,xarg);
                    }catch (IllegalAccessException e){
                        System.out.println(e);
                    }catch (InvocationTargetException ite){
                    }
                }
            });
        } catch (Exception e){
            System.out.println(e);
        }
    }

}
public static void setBridge(WebEngine we){
    JSObject jsobj = (JSObject) we.executeScript("window");
    Bridge b = new Bridge();
    jsobj.setMember("b4j", b);
}
#end if


#Region designer 1.bjl
#If txttxt

    WebView: wv

     ------

    Label1:"in B4J"
    TextArea1:" ", Button1: "send to WebView"

#End If
#End Region


#Region show content of  'c:/B4X/wv30.html
#If txtxt

<!doctype html><html lang="en-US">
<head>
<script type="text/javascript">
    // B4JSub2jsWV
    function B4J2wv(message){
        document.getElementById("inputField").value = message;
    }
    // jsWV2B4JSub
    function wv2B4J(){
       var msg = document.getElementById("inputField").value;
       b4j.link2('teststr',msg)
    }
    function wvInt2B4J(){
       var msg = document.getElementById("inputInt").value;
       msg = parseInt(0 + msg)
       b4j.link2('testint',  msg )
    }
</script>
<style>
    .tit {
        color:#b69221;
        font-size:300%;
        margin-top:-11px;
    }
    body {
       background-color:#fbd7bd;
    }
</style></head>
<body>
<center><h1 class="tit">in WebView </h1></center>
    <input id="inputField"  type="text" value="">
    <input onClick="wv2B4J()"  type="button" value="send str to B4J"/>
    <br>
    <input id="inputInt"  type="text" value="">
    <input onClick="wvInt2B4J()"  type="button" value="send int to B4J"/>
    <!--input id="inputFieldtest"  type="text" value="test">
    <br><button Type="button" onClick="myfunction()">Click myfunc</button-->
</body></html>


#End If
#End Region
 
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