Android Calling JavaScript functions in WebView

Question

I am trying to call some javascript functions sitting in an html page running inside an android webview. Pretty simple what the code tries to do below - from the android app, call a javascript function with a test message, which inturn calls a java function back in the android app that displays test message via toast.

The javascript function looks like:

function testEcho(message){      window.JSInterface.doEchoTest(message); } 

From the WebView, I have tried calling the javascript the following ways with no luck:

myWebView.loadUrl("javascript:testEcho(Hello World!)"); mWebView.loadUrl("javascript:(function () { " + "testEcho(Hello World!);" + "})()"); 

I did enable javascript on the WebView

myWebView.getSettings().setJavaScriptEnabled(true); // register class containing methods to be exposed to JavaScript myWebView.addJavascriptInterface(myJSInterface, "JSInterface");  

And heres the Java Class

public class JSInterface{  private WebView mAppView; public JSInterface  (WebView appView) {         this.mAppView = appView;     }      public void doEchoTest(String echo){         Toast toast = Toast.makeText(mAppView.getContext(), echo, Toast.LENGTH_SHORT);         toast.show();     } } 

I've spent a lot of time googling around to see what I may be doing wrong. All examples I have found use this approach. Does anyone see something wrong here?

Edit: There are several other external javascript files being referenced & used in the html, could they be the issue?

Answer 1

I figured out what the issue was : missing quotes in the testEcho() parameter. This is how I got the call to work:

myWebView.loadUrl("javascript:testEcho('Hello World!')");