Skip to main content

Android - The radio group creation and event handler mechanism

 This is very simple example for creating check box in android application. Here I have created the new android project and I have modified the main.xml file with following code.
 Here I have created the one radio grop and I have added some games names as option. Now I am going to display the selected game with using TextView. For getting this effect I have modified the main activity java file with following code.

import android.app.Activity;
import android.os.Bundle;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;
import android.widget.TextView;

public class RadioBoxActivity extends Activity implements OnCheckedChangeListener{
    /** Called when the activity is first created. */
       RadioGroup radioGroup;
       TextView textView;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        radioGroup = (RadioGroup)findViewById(R.id.radioGroup1);
        textView = (TextView)findViewById(R.id.textView1);
        radioGroup.setOnCheckedChangeListener(this);
    }

       @Override
       public void onCheckedChanged(RadioGroup group, int checkedId) {
              // TODO Auto-generated method stub
              int myCheckedRadioId = radioGroup.getCheckedRadioButtonId();
              String displayStr = "";
              if(myCheckedRadioId == R.id.radio0) {
                     displayStr = "My favorite game is Cricket" ;
              }
              else if(myCheckedRadioId == R.id.radio1) {
                     displayStr = "My favorite game is Hockey" ;
              }
              else {
                     displayStr = "My favorite game is Football" ;
              }
              textView.setText(displayStr);
       }
}
 Here I have taken the radio group handle and text view handle through using findViewById method. For adding action listener to radio group, I have implemented the OnCheckedChangeListener interface and I have override the onCheckedChanged() method. In this method I have get the selected radio id using getCheckedRadioButtonId() method. After that I have used this selected id value for finding selected game through comparing this selected id value with all the radio id value. At last I have changed the text view value with computed string. The filnal result should be like this only.






Labels:

Comments

Post a Comment

Popular posts from this blog

Ext JS 4 – Creating web page using Ext.container.Viewport class and region propery

The Ext.container.Viewport is used for creating general web page and region property is used for splitting web page into different parts. Ext.container.Viewport is a specialized container represents the viewable area of the application (the browser area). It render itself to the document body, there is no need for providing renderTo property and it automatically sizes itself to size of the browser viewport. The viewport also re-size the child elements based on view area(based on browser width and height). The default layout of the viewport is border layout and we can customize this property according to our requirements. The viewport does not provide any scrolling. If necessary, the child elements(generally panels) within viewport needs to provide a scroll feature by using autoScroll property. See the below example for better understanding. This is Home.js file placed into app/view folder. Ext.define('MyApp.view.Home', { extend : 'Ext.container.Viewport&#
4 comments
Read more

Getting servlet init parameter that is defined in web.xml

1. Create a new dynamic web project using eclipse. 2. Create a one new servlet and include the following code. package com.controller ; import java.io.IOException; import javax.servlet .ServletConfig; import javax.servlet .ServletException; import javax.servlet .annotation.WebServlet; import javax.servlet .http.HttpServlet; import javax.servlet .http.HttpServletRequest; import javax.servlet .http.HttpServletResponse; @ WebServlet ( "/LoginController" ) public class LoginController extends HttpServlet {                 private static final long serialVersionUID = 1L;                 public LoginController() {         super ();     }     protected void doPost( HttpServletRequest request, HttpServletResponse response) throws ServletException , IOException {                                 ServletConfig config = getServletConfig ();                                 System.out.println( "Init parameter user nam
1 comment
Read more

Simple Login Application Using Spring MVC and Hibernate – Part 1

 I hope developers working in web application development might hear about MVC architecture. Almost all technologies provide support for MVC based web application development, but the success is based on many factors like reusable of the code, maintenance of the code, future adaption of the code, etc..,  The success of the Spring MVC is “ Open for extension and closed for modification ” principle. Using Spring MVC the developers can easily develop MVC based web application. We don’t need any steep learning curve at the same time we need to know the basics of spring framework and MVC architecture. The Spring MVC consists of following important components. 1. Dispatcher servlet 2. Controller 3. View Resolver 4. Model Spring MVC - Overview  The overall architecture of Spring MVC is shown here.  1. When “Dispatcher Servlet” gets any request from client, it finds the corresponding mapped controller for the request and just dispatches the request to the corresponding contro
60 comments
Read more