menu1.java.bak

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//: Menu1.java
// Menus work only with Frames.
// Shows submenus, checkbox menu items
// and swapping menus.
import java.awt.*;

public class Menu1 extends Frame {
	String[] flavors = { "Chocolate", "Strawberry",
		"Vanilla Fudge Swirl", "Mint Chip",
		"Mocha Almond Fudge", "Rum Raisin",
		"Praline Cream", "Mud Pie" };
	TextField t = new TextField("No flavor", 30);
	MenuBar mb1 = new MenuBar();
	Menu f = new Menu("File");
	Menu m = new Menu("Flavors");
	Menu s = new Menu("Safety");
	// Alternative approach:
	CheckboxMenuItem[] safety = {
		new CheckboxMenuItem("Guard"),
		new CheckboxMenuItem("Hide")
	};
	MenuItem[] file = {
		new MenuItem("Open"),
		new MenuItem("Exit")
	};
	// A second menu bar to swap to:
	MenuBar mb2 = new MenuBar();
	Menu fooBar = new Menu("fooBar");
	MenuItem[] other = {
		new MenuItem("Foo"),
		new MenuItem("Bar"),
		new MenuItem("Baz"),
	};
	Button b = new Button("Swap Menus");

	public Menu1() {
		for(int i = 0; i < flavors.length; i++) {
			m.add(new MenuItem(flavors[i]));
			// Add separators at intervals:
			if((i+1) % 3 == 0)
				m.addSeparator();
		}
		for(int i = 0; i < safety.length; i++)
			s.add(safety[i]);
		f.add(s);
		for(int i = 0; i < file.length; i++)
			f.add(file[i]);
		mb1.add(f);
		mb1.add(m);
		setMenuBar(mb1);
		t.setEditable(false);
		add("Center", t);
		// Set up the system for swapping menus:
		add("North", b);
		for(int i = 0; i < other.length; i++)
			fooBar.add(other[i]);
		mb2.add(fooBar);
	}

	public boolean handleEvent(Event evt) {
		if(evt.id == Event.WINDOW_DESTROY)
			System.exit(0);
		else
			return super.handleEvent(evt);
		return true;
	}
	
	public boolean action(Event evt, Object arg) {
		if(evt.target.equals(b)) {
			MenuBar m = getMenuBar();
			if(m == mb1) 
				setMenuBar(mb2);
			else if (m == mb2) 
				setMenuBar(mb1);
		}
		else if(evt.target instanceof MenuItem) {
			if(arg.equals("Open")) {
				String s = t.getText();
				boolean chosen = false;
				for(int i = 0; i < flavors.length; i++)
					if(s.equals(flavors[i])) 
						chosen = true;
				if(!chosen)
					t.setText("Choose a flavor first!");
				else
					t.setText("Opening "+ s +". Mmm, mm!");
			}
			else if(evt.target.equals(file[1]))
				System.exit(0);
			// CheckboxMenuItems cannot use String
			// matching; you must match the target:
			else if(evt.target.equals(safety[0]))
				t.setText("Guard the Ice Cream! " +
					"Guarding is " + safety[0].getState());
			else if(evt.target.equals(safety[1]))
				t.setText("Hide the Ice Cream! " +
					"Is it cold? " + safety[1].getState());
			else
				t.setText(arg.toString());
		}
		else
			return super.action(evt, arg);
		return true;
	}
	
	public static void main(String[] args) {
		Menu1 f = new Menu1();
		f.resize(300,200);
		f.show();
	}
} ///:~