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Android Build a Blog Reader Android App Using Intents to Display and Share Posts Opening a Webpage Within the App

Posted by Steve Hunter
Steve Hunter
57,712 Points

NullPointerException in BlogWebViewActivity

I'm having trouble with showing the blog contents in the WebView. The program crashes with the above exception.

I've tried to use the debugger but I'm getting nowhere with that - the error is hidden.

I commented out the newly added code that caused the issue and then added the lines back one-by-one whilst adding a Log.e to see where I'm getting up to.

The NullPointerException is thrown by

webView.loadUrl(blogUri.toString());

I've output the contents of blogUri.toString() in the console - this is fine; a valid web address is displayed, i.e. not null.

I've tried this in the emulator and on a device with the same result. I've also amended my doInBackGround method as described in a forum post somewhere - same issue persists.

Any help would be appreciated!

Cheers,

Steve.

3 Answers

Steve Hunter
Steve Hunter
57,712 Points

The URI and WebView are created with:

Uri blogUri = intent.getData();
WebView webView = (WebView) findViewById(R.id.webView1);

I think that's correct?

J Andrew Scott
J Andrew Scott
30,626 Points

In that case, I would verify that you're first loading the correct layout with setContentView() and that it contains a WebView with the id @+id/webView1.

J Andrew Scott
J Andrew Scott
30,626 Points
J Andrew Scott
J Andrew Scott
30,626 Points

The only other pointer in that line is the webView. Are you sure it's properly assigned? Otherwise, I'd have to see the backtrace in your logcat to see what's going wrong.

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

I have 

setContentView(R.layout.activity_blog_web_view);

that's the same name as the .xml file.

However! The webView1 is in a fragment, not the activity - that'll cause problems!

corrects cock-up

tests

THANK YOU!!! :-)

That now works fine.

Steve.