How to do if I want blend two different colors using JButton?
<p>I have just started learning GUI in java yesterday.
And I want say sorry with my english because I'm not a native english speaker, but I hope everybody could understand my question. 
I did 3~4 examples about JFrame , JButton, JRadioButton, JComponent,  JToggleButton which were written in my book.</p>

<p>And! Now I'm doing my own example.  First, I thought to create a screen which shows that color which I want using JButton and JLabel. </p>

<pre><code>import javax.swing.*;
import java.awt.event.*; 
import java.awt.*;

public class JButton_Color extends JFrame implements ActionListener{
private JLabel screen = new JLabel("");
private JButton col1 = new JButton("Blue");
private JButton col2 = new JButton("Green");
private JButton col3 = new JButton("Pink");

public JButton_Color(){
setLayout(new GridLayout(2,2));
add(screen); add(col1); add(col2); add(col3);
getContentPane().setBackground(Color.white);
screen.setOpaque(true);
col1.addActionListener(this);
col2.addActionListener(this);
col3.addActionListener(this);
setSize(100,200);
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);

}
public void actionPerformed(ActionEvent e){
Object action = e.getSource();

if(action == col1)
    screen.setBackground(Color.blue);

else if ( action == col2)
    screen.setBackground(Color.green);
else if ( action == col3)
    screen.setBackground(Color.pink);

 }  
 public static void main (String[] args){
 JButton_Color j_c = new JButton_Color();
 }
 }
</code></pre>

<p>It works perfectly, but it is not my final goal. I want to blend two colors which I clicked on. So, just for a test, I changed method actionPerformed little bit like that :</p>

<pre><code>public void actionPerformed(ActionEvent e){
Object action = e.getSource();
for (int i =0; i&lt;2; i++){
if(action == col1)
    screen.setBackground(Color.blue);

else if ( action == col2)
    screen.setBackground(Color.green);
else if ( action == col3)
    screen.setBackground(Color.pink);
else if((action==col1)&amp;&amp;(action==col2))
    screen.setBackground(Color.yellow);

}
}
</code></pre>

<p>But that did not go well. How should I change my code? Actually, I have never learned about actionlistener and events.. but I want to achieve my goal!  </p>