/*
* This file is part of lanterna (https://github.com/mabe02/lanterna).
*
* lanterna is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright (C) 2010-2020 Martin Berglund
* Copyright (C) 2017 Bruno Eberhard
* Copyright (C) 2017 University of Waikato, Hamilton, NZ
*/
package com.googlecode.lanterna.gui2.menu;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import com.googlecode.lanterna.TerminalPosition;
import com.googlecode.lanterna.TerminalSize;
import com.googlecode.lanterna.gui2.AbstractComponent;
import com.googlecode.lanterna.gui2.Component;
import com.googlecode.lanterna.gui2.ComponentRenderer;
import com.googlecode.lanterna.gui2.Container;
import com.googlecode.lanterna.gui2.Interactable;
import com.googlecode.lanterna.gui2.InteractableLookupMap;
import com.googlecode.lanterna.gui2.TextGUIGraphics;
import com.googlecode.lanterna.gui2.Window;
import com.googlecode.lanterna.input.KeyStroke;
A menu bar offering drop-down menus. You can attach a menu bar to a Window
by using the Window.setMenuBar(MenuBar)
method, then use add(Menu)
to add sub-menus to the menu bar. Author: FracPete (fracpete at waikato dot ac dot nz), Bruno Eberhard, Martin Berglund
/**
* A menu bar offering drop-down menus. You can attach a menu bar to a {@link Window} by using the
* {@link Window#setMenuBar(MenuBar)} method, then use {@link MenuBar#add(Menu)} to add sub-menus to the menu bar.
*
* @author FracPete (fracpete at waikato dot ac dot nz)
* @author Bruno Eberhard
* @author Martin Berglund
*/
@SuppressWarnings("SuspiciousMethodCalls")
public class MenuBar extends AbstractComponent<MenuBar> implements Container {
private static final int EXTRA_PADDING = 0;
private final List<Menu> menus;
Creates a new menu bar
/**
* Creates a new menu bar
*/
public MenuBar() {
this.menus = new CopyOnWriteArrayList<>();
}
Adds a new drop-down menu to the menu bar, at the end
Params: - menu – Menu to add to the menu bar
Returns: Itself
/**
* Adds a new drop-down menu to the menu bar, at the end
* @param menu Menu to add to the menu bar
* @return Itself
*/
public MenuBar add(Menu menu) {
menus.add(menu);
menu.onAdded(this);
return this;
}
@Override
public int getChildCount() {
return getMenuCount();
}
@Override
public List<Component> getChildrenList() {
return new ArrayList<>(menus);
}
@Override
public Collection<Component> getChildren() {
return getChildrenList();
}
@Override
public boolean containsComponent(Component component) {
return menus.contains(component);
}
@Override
public synchronized boolean removeComponent(Component component) {
boolean hadMenu = menus.remove(component);
if (hadMenu) {
component.onRemoved(this);
}
return hadMenu;
}
@Override
public synchronized Interactable nextFocus(Interactable fromThis) {
if (menus.isEmpty()) {
return null;
}
else if (fromThis == null) {
return menus.get(0);
}
else if (!menus.contains(fromThis) || menus.indexOf(fromThis) == menus.size() - 1) {
return null;
}
else {
return menus.get(menus.indexOf(fromThis) + 1);
}
}
@Override
public Interactable previousFocus(Interactable fromThis) {
if (menus.isEmpty()) {
return null;
}
else if (fromThis == null) {
return menus.get(menus.size() - 1);
}
else if (!menus.contains(fromThis) || menus.indexOf(fromThis) == 0) {
return null;
}
else {
return menus.get(menus.indexOf(fromThis) - 1);
}
}
@Override
public boolean handleInput(KeyStroke key) {
return false;
}
Returns the drop-down menu at the specified index. This method will throw an Array
Params: - index – Index of the menu to return
Throws: - IndexOutOfBoundsException – if the index is out of range
Returns: The drop-down menu at the specified index
/**
* Returns the drop-down menu at the specified index. This method will throw an Array
* @param index Index of the menu to return
* @return The drop-down menu at the specified index
* @throws IndexOutOfBoundsException if the index is out of range
*/
public Menu getMenu(int index) {
return menus.get(index);
}
Returns the number of menus this menu bar currently has
Returns: The number of menus this menu bar currently has
/**
* Returns the number of menus this menu bar currently has
* @return The number of menus this menu bar currently has
*/
public int getMenuCount() {
return menus.size();
}
@Override
protected ComponentRenderer<MenuBar> createDefaultRenderer() {
return new DefaultMenuBarRenderer();
}
@Override
public synchronized void updateLookupMap(InteractableLookupMap interactableLookupMap) {
for (Menu menu: menus) {
interactableLookupMap.add(menu);
}
}
@Override
public TerminalPosition toBasePane(TerminalPosition position) {
// Assume the menu is always at the top of the content panel
return position;
}
public boolean isEmptyMenuBar() {
return false;
}
The default implementation for rendering a MenuBar
/**
* The default implementation for rendering a {@link MenuBar}
*/
public class DefaultMenuBarRenderer implements ComponentRenderer<MenuBar> {
@Override
public TerminalSize getPreferredSize(MenuBar menuBar) {
int maxHeight = 1;
int totalWidth = EXTRA_PADDING;
for (int i = 0; i < menuBar.getMenuCount(); i++) {
Menu menu = menuBar.getMenu(i);
TerminalSize preferredSize = menu.getPreferredSize();
maxHeight = Math.max(maxHeight, preferredSize.getRows());
totalWidth += preferredSize.getColumns();
}
totalWidth += EXTRA_PADDING;
return new TerminalSize(totalWidth, maxHeight);
}
@Override
public void drawComponent(TextGUIGraphics graphics, MenuBar menuBar) {
// Reset the area
graphics.applyThemeStyle(getThemeDefinition().getNormal());
graphics.fill(' ');
int leftPosition = EXTRA_PADDING;
TerminalSize size = graphics.getSize();
int remainingSpace = size.getColumns() - EXTRA_PADDING;
for (int i = 0; i < menuBar.getMenuCount() && remainingSpace > 0; i++) {
Menu menu = menuBar.getMenu(i);
TerminalSize preferredSize = menu.getPreferredSize();
menu.setPosition(menu.getPosition()
.withColumn(leftPosition)
.withRow(0));
int finalWidth = Math.min(preferredSize.getColumns(), remainingSpace);
menu.setSize(menu.getSize()
.withColumns(finalWidth)
.withRows(size.getRows()));
remainingSpace -= finalWidth + EXTRA_PADDING;
leftPosition += finalWidth + EXTRA_PADDING;
TextGUIGraphics componentGraphics = graphics.newTextGraphics(menu.getPosition(), menu.getSize());
menu.draw(componentGraphics);
}
}
}
}