Intent it = new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.baidu.com"));

     it.setClassName("com.android.browser", "com.android.browser.BrowserActivity");

     getContext().startActivity(it);  

Intent intent=new Intent();

intent.setAction("android.intent.action.VIEW");

Uri CONTENT_URI_BROWSERS = Uri.parse("content://com.android.htmlfileprovider/sdcard/123.html");

intent.setData(CONTENT_URI_BROWSERS);

intent.setClassName("com.android.browser", "com.android.browser.BrowserActivity");

startActivity(intent);