Android: ANDROID BROWSER

1.Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.google.com"));
startActivity(browserIntent);

2.
if (!url.startsWith("http://") && !url.startsWith("https://"))
   url = "http://" + url;

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http://www.pocketmagic.net/?p=1776

y Radu Motisan Posted on March 18th, 2011

Based on the info in my previous article I'd like to present the steps to create a simple Android Internet Browser application, with a header, a WebView central area and a footer - all dynamical, without using XMLs:

Some details:

In AndroidManifest.xml, you will need to include the INTERNET permissions:

<uses-permission android:name="android.permission.INTERNET" />

The interface: you can learn how to use the nice RelativeLayout control and create the interface, as per my previous article on this topic. The user controls are the top address field and the GO button, the BACK, FORWARD, RELOAD and STOP at the bottom.

The WebView control: will handle all the HTML rendering and other complex function related to internet browsers. The webview is created between the Header and the Footer, and the content is finger-friendly (finger scrollable). By default the zoom level has been configured to fit the pages in the screen's width.

For the WebView control I've enabled JavaScript support and added a WebViewClient class to intercept the various events like page loading events (start/ready):

 
m_web.getSettings().setJavaScriptEnabled(true);
m_web.setWebViewClient(new MyWebViewClient());

Note: The WebView Client class is quite simple:

 
private class MyWebViewClient extends WebViewClient {
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
 Log.d(LOG_TAG, "onPageStarted");
 m_tv.setText("Loading page...");
 //stop button is enabled only when pages are loading
 m_bButStop.setEnabled(true);
}
@Override
public void onPageFinished(WebView view, String url) {
 Log.d(LOG_TAG, "onPageFinished");
 m_tv.setText("Ready ");
 //stop button is disabled when pages are already loaded
 m_bButStop.setEnabled(false);
 // This call inject JavaScript into the page which just finished loading.
 m_web.loadUrl("javascript:window.HTMLOUT.showHTML('<head>'+document.getElementsByTagName('html')[0].innerHTML+'</head>');");
 // adjust prev/next buttons, only if history is available
 m_bButBack.setEnabled(m_web.canGoBack());
 m_bButFwd.setEnabled(m_web.canGoForward());
}
 
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
 view.loadUrl(url);
 return true;
}
 
}

Details:

When the page starts loading (onPageStarted) we set the proper content in the status textview, and we enable the STOP button. This button is enabled when a page is loading, and is disabled when the page is completely loaded, because it doesn't make sense to stop something that has already finished loading, does it?

When the page is loaded (onPageFinished) we show "Ready" in the status textview, we disable the STOP button, and we inject a JavaScript so we would have access to the HTML code of the page we've loaded.
To run the Javascript we need to call :

 
// set java script used to get the HTML code
m_web.addJavascriptInterface(new JavaScriptInterface(), "HTMLOUT");

Where the JavaScriptInterface is a simple HTML reader based on the "showHTML" function (that we call after a page is loaded):

 
// Used with Webview, to get the HTML code
class JavaScriptInterface{
public void showHTML(String html) {
 m_nHTMLSize = 0;
 if (html !=null) {
  //int i = html.lastIndexOf(""); //search for something in the text
  m_nHTMLSize = html.length();
  Log.d(LOG_TAG, "HTML content is: "+html+"\nSize:"+m_nHTMLSize+" bytes");
 
 }
}
}

The Third of the page-related events, is shouldOverrideUrlLoading:

 
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
 view.loadUrl(url);
 return true;
}

Android

Tuesday, May 24, 2011

ANDROID BROWSER

y Radu Motisan Posted on March 18th, 2011

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