package examples;
import java.awt.*;
import javax.swing.*;
import static java.awt.BorderLayout.*;

public class GUI extends JPanel {
	JButton button;
	JSlider slider;
	JCheckBox box;
	JTextArea text;
	static final GridBagConstraints gbc = new GridBagConstraints();
	static enum LayoutChoice {flow, border, grid, gridbag};
	
	public GUI(LayoutChoice lc) {
		createComponents();
		switch (lc) {
		case flow: addComponentsFlow(); break;
		case border: addComponentsBorder(); break;
		case grid: addComponentsGrid(); break;
		case gridbag: addComponentsGridBag();
		}
	}
	
	void createComponents() {
		button = new JButton("press me");
		slider = new JSlider();
		box = new JCheckBox("useless option");
		text = new JTextArea("abc def");
	}
	
	void addComponentsFlow() {
		setLayout(new FlowLayout());
		add(button);
		add(slider);
		add(box);
		add(new JScrollPane(text));
	}
	
	void addComponentsGrid() {
		setLayout(new GridLayout(2,2));
		add(button);
		add(slider);
		add(box);
		add(new JScrollPane(text));
	}
	
	void addComponentsBorder() {
		setLayout(new BorderLayout());
		add(button,WEST);
		add(slider,SOUTH);
		add(box,NORTH);
		add(new JScrollPane(text),CENTER);
	}
	
	void addComponentsGridBag() {
		setLayout(new GridBagLayout());
		add(button,0,0,1,2);
		add(slider,0,3,2,1);
		add(box,1,0,2,1);
		JScrollPane jsp = new JScrollPane(text);
		jsp.setPreferredSize(new Dimension(300,100));
		add(jsp,0,5,2,2);
		GUI g = new GUI(LayoutChoice.border);
		g.setPreferredSize(new Dimension(300,200));
		add(g,0,7,2,3);
	}
	
	void add(JComponent c, int x, int y, int width, int height) {
		gbc.gridx = x;
		gbc.gridy = y;
		gbc.gridwidth = width;
		gbc.gridheight = height;
		gbc.anchor = GridBagConstraints.EAST;
		add(c, gbc);
	}
	
	public static void main(String[] args) {
		GUI g = new GUI(LayoutChoice.gridbag);
		JFrame f = new JFrame("My GUI");
		f.getContentPane().add(g);
		f.pack();
		f.setVisible(true);
	}
}