I have a android program (Java + html in a webview). I can call from the javascript to the Java code. But the other way around stopped working (after updating in eclipse).
So this is what I'm trying to do
I tried to let it work with the WebView in the MainActivity, but it didnt work.
MainActivity.java
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final WebView webView = (WebView)findViewById(R.id.webView);
webView.getSettings().setJavaScriptEnabled(true);
webView.setWebChromeClient(new WebChromeClient());
WebSettings webSettings = webView.getSettings();
webSettings.setJavaScriptEnabled(true);
javascr = new Javascript(this, webView);
webView.addJavascriptInterface(javascr, "AndroidFunction");
webView.loadUrl("file:///android_asset/www/index.html");
....
}
Javascript.java
public class Javascript {
Context cont;
WebView webView;
Javascript(Context c, WebView w) {
cont = c;
webView = w;
}
// function called in the javascript by AndroidFunction.test();
public void test() {
// Breaking point!!!
webView.loadUrl("javascript:helloBack()");
}
Error:
03-24 11:47:50.103: W/WebView(21026): at com.android.org.chromium.base.SystemMessageHandler.handleMessage(SystemMessageHandler.java:27)
03-24 11:47:50.103: W/WebView(21026): java.lang.Throwable: A WebView method was called on thread 'JavaBridge'. All WebView methods must be called on the same thread. (Expected Looper Looper{41ab68f8} called on Looper{41bb70a8}, FYI main Looper is Looper{41ab68f8})
03-24 11:47:50.103: W/WebView(21026): at android.webkit.WebView.checkThread(WebView.java:2063)
03-24 11:47:50.103: W/WebView(21026): at android.webkit.WebView.loadUrl(WebView.java:794)
03-24 11:47:50.103: W/WebView(21026): at com.example.hellobt.Javascript.test(Javascript.java:24)
03-24 11:47:50.103: W/WebView(21026): at com.android.org.chromium.base.SystemMessageHandler.nativeDoRunLoopOnce(Native Method)
03-24 11:47:50.103: W/WebView(21026): at com.android.org.chromium.base.SystemMessageHandler.handleMessage(SystemMessageHandler.java:27)
03-24 11:47:50.103: W/WebView(21026): at android.os.Handler.dispatchMessage(Handler.java:102)
03-24 11:47:50.103: W/WebView(21026): at android.os.Looper.loop(Looper.java:137)
03-24 11:47:50.103: W/WebView(21026): at android.os.HandlerThread.run(HandlerThread.java:61)
Thanks for the answer. I edited the function in my Javascript file like this:
private void test(final String s) {
webView.post(new Runnable() {
public void run() {
webView.loadUrl("javascript:" + s + ";");
}
});
System.out.println("javscript done..");
}
The JavaScript method is executed on a background (i.e. non-UI) thread. You need to call all Android View related methods on the UI thread. You can achieve what you need with:
mWebView.post(new Runnable() {
@Override
public void run() {
mWebView.loadUrl(...).
}
});
Which will post the task to run on the UI thread.