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So i know there are other posts addressing the same issue, and I think I've followed them to the letter but alas to no avail. I'm trying to learn how to get my app to interact with javascript. I just want to be able to return a value from my javascript to my activity.
here is my activity:
public class JSExample extends Activity {
WebView mWebView;
String mString;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mWebView = (WebView)findViewById(R.id.mWebView);
mWebView.addJavascriptInterface(new ClsAccessor(), "accessor");
String html = getAssetsContent("jsinterface.html");
mWebView.loadDataWithBaseURL(null, html, "text/html", "UTF-8", null);
// Log.d("YO!", mString);
}
private String getAssetsContent(String filename){
.....
}
private void closeStream(BufferedReader stream) {
.....
}
class ClsAccessor{
public void setValue(String value){
JSExample.this.mString = value;
}
}
Here is the html file loaded by my WebView that contains the javascript i want to run:
<!DOCTYPE html>
<html>
<head>
<script language="javascript">
accessor.setValue('Hello!');
</script>
</head>
<body>
<h1>Testing</h1>
</body>
</html>
This does not work. When i run the code with "Log.d("YO!", mString);" uncommented I get a null pointer exception, which means that the javascript never assigned a value to mString. what am i doing wrong?
497
This may not be correct, I will have to double check but it may be due to the reference being lost..
Try making your ClsAccessor reference a member level one..
public class JSExample extends Activity {
...
ClsAccessor _accessor = new ClsAccessor();
...
public void onCreate(Bundle savedInstanceState) {
...
mWebView.addJavascriptInterface(_accessor, "accessor");
...
Also if you debug line by line does setValue() ever get called in managed code?
For what it is worth, I have code that is doing as I have described above and the script to managed interface works fine, however I am not in a position currently to test and see if not having a reference to the class also works.
91
Try enabling javascript on your webview :
mWebview.getSettings().setJavaScriptEnabled(true);
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