Exercise : 2

To understand Activity, Intent

a. Create sample application with login module.(Check username and password)

b. On successful login, go to next screen. And on failing login, alert user using Toast.

c. Also pass username to next screen

Screen Shot:

XML :

main.xml :

JAVA :

SecondActivity.java :

package kmn.Second;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class SecondActivity extends Activity implements OnClickListener
{
    /** @author GTU MCA PPT, www.gtumcappt.com */
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Button login = (Button)findViewById(R.id.btnlogin);
        Button clear = (Button)findViewById(R.id.btnclear);
        login.setOnClickListener(this);
        clear.setOnClickListener(this);
    }
    public void onClick(View v)
    {
     EditText username = (EditText)findViewById(R.id.txtusername);
     EditText password =(EditText)findViewById(R.id.txtpassword);
     if(v.getId()==R.id.btnlogin)
     {
if(username.getText().toString().equals("keval") && password.getText().toString().equals("nagaria"))
      {
       //Toast.makeText(this, "ok", Toast.LENGTH_LONG).show();
       Intent i = new Intent(this,S2.class);
       i.putExtra("username", username.getText().toString());
       startActivity(i);
      }
      else
      {
       Toast.makeText(this, "Error", Toast.LENGTH_LONG).show();
      }
     }
     if(v.getId()==R.id.btnclear)
     {
      username.setText("");
      password.setText("");
     }
    }
}

S2.java :

package kmn.Second;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;

public class S2 extends Activity 
{
    /** @author GTU MCA PPT, www.gtumcappt.com */
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Intent i = getIntent();
        //Toast.makeText(this, "Welcome",Toast.LENGTH_LONG).show();
        String username=i.getStringExtra("username");       
        TextView tv=new TextView(this);
        Button btnBack = new Button(this);
        btnBack.setText("Back");
        tv.setText("Welcome "+username+" !");
        tv.setTextColor(Color.rgb(255, 255, 100));            
        tv.setTextSize(25);
        LinearLayout ll = new LinearLayout(this);
  ll.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,      LayoutParams.FILL_PARENT));
        ll.setOrientation(LinearLayout.VERTICAL);
        ll.addView(tv);
        ll.addView(btnBack);
        setContentView(ll);
        
        btnBack.setOnClickListener(new Button.OnClickListener()
        {
         public void onClick(View v)
         {
          setContentView(R.layout.main);
         }        
        });
 }

}