/*
* This file is part of lanterna (http://code.google.com/p/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) 2010-2017 Martin Berglund
*/
package com.googlecode.lanterna.gui2;
import com.googlecode.lanterna.TerminalSize;
import com.googlecode.lanterna.graphics.ThemeDefinition;
import com.googlecode.lanterna.graphics.ThemeStyle;
import com.googlecode.lanterna.input.KeyStroke;
import com.googlecode.lanterna.input.KeyType;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
/**
* This is a list box implementation where each item has its own checked state that can be toggled on and off
* @author Martin
*/
public class CheckBoxList<V> extends AbstractListBox<V, CheckBoxList<V>> {
/**
* Listener interface that can be attached to the {@code CheckBoxList} in order to be notified on user actions
*/
public interface Listener {
/**
* Called by the {@code CheckBoxList} when the user changes the toggle state of one item
* @param itemIndex Index of the item that was toggled
* @param checked If the state of the item is now checked, this will be {@code true}, otherwise {@code false}
*/
void onStatusChanged(int itemIndex, boolean checked);
}
private final List<Listener> listeners;
private final List<Boolean> itemStatus;
/**
* Creates a new {@code CheckBoxList} that is initially empty and has no hardcoded preferred size, so it will
* attempt to be as big as necessary to draw all items.
*/
public CheckBoxList() {
this(null);
}
/**
* Creates a new {@code CheckBoxList} that is initially empty and has a pre-defined size that it will request. If
* there are more items that can fit in this size, the list box will use scrollbars.
* @param preferredSize Size the list box should request, no matter how many items it contains
*/
public CheckBoxList(TerminalSize preferredSize) {
super(preferredSize);
this.listeners = new CopyOnWriteArrayList<Listener>();
this.itemStatus = new ArrayList<Boolean>();
}
@Override
protected ListItemRenderer<V,CheckBoxList<V>> createDefaultListItemRenderer() {
return new CheckBoxListItemRenderer<V>();
}
@Override
public synchronized CheckBoxList<V> clearItems() {
itemStatus.clear();
return super.clearItems();
}
@Override
public CheckBoxList<V> addItem(V object) {
return addItem(object, false);
}
@Override
public synchronized V removeItem(int index) {
V item = super.removeItem(index);
itemStatus.remove(index);
return item;
}
/**
* Adds an item to the checkbox list with an explicit checked status
* @param object Object to add to the list
* @param checkedState If <code>true</code>, the new item will be initially checked
* @return Itself
*/
public synchronized CheckBoxList<V> addItem(V object, boolean checkedState) {
itemStatus.add(checkedState);
return super.addItem(object);
}
/**
* Checks if a particular item is part of the check box list and returns a boolean value depending on the toggle
* state of the item.
* @param object Object to check the status of
* @return If the item wasn't found in the list box, {@code null} is returned, otherwise {@code true} or
* {@code false} depending on checked state of the item
*/
public synchronized Boolean isChecked(V object) {
if(indexOf(object) == -1)
return null;
return itemStatus.get(indexOf(object));
}
/**
* Checks if a particular item is part of the check box list and returns a boolean value depending on the toggle
* state of the item.
* @param index Index of the item to check the status of
* @return If the index was not valid in the list box, {@code null} is returned, otherwise {@code true} or
* {@code false} depending on checked state of the item at that index
*/
public synchronized Boolean isChecked(int index) {
if(index < 0 || index >= itemStatus.size())
return null;
return itemStatus.get(index);
}
/**
* Programmatically sets the checked state of an item in the list box
* @param object Object to set the checked state of
* @param checked If {@code true}, then the item is set to checked, otherwise not
* @return Itself
*/
public synchronized CheckBoxList<V> setChecked(V object, boolean checked) {
int index = indexOf(object);
if(index != -1) {
setChecked(index, checked);
}
return self();
}
private void setChecked(final int index, final boolean checked) {
itemStatus.set(index, checked);
runOnGUIThreadIfExistsOtherwiseRunDirect(new Runnable() {
@Override
public void run() {
for(Listener listener: listeners) {
listener.onStatusChanged(index, checked);
}
}
});
}
/**
* Returns all the items in the list box that have checked state, as a list
* @return List of all items in the list box that has checked state on
*/
public synchronized List<V> getCheckedItems() {
List<V> result = new ArrayList<V>();
for(int i = 0; i < itemStatus.size(); i++) {
if(itemStatus.get(i)) {
result.add(getItemAt(i));
}
}
return result;
}
/**
* Adds a new listener to the {@code CheckBoxList} that will be called on certain user actions
* @param listener Listener to attach to this {@code CheckBoxList}
* @return Itself
*/
public synchronized CheckBoxList<V> addListener(Listener listener) {
if(listener != null && !listeners.contains(listener)) {
listeners.add(listener);
}
return this;
}
/**
* Removes a listener from this {@code CheckBoxList} so that if it had been added earlier, it will no longer be
* called on user actions
* @param listener Listener to remove from this {@code CheckBoxList}
* @return Itself
*/
public CheckBoxList<V> removeListener(Listener listener) {
listeners.remove(listener);
return this;
}
@Override
public synchronized Result handleKeyStroke(KeyStroke keyStroke) {
if(keyStroke.getKeyType() == KeyType.Enter ||
(keyStroke.getKeyType() == KeyType.Character && keyStroke.getCharacter() == ' ')) {
if(itemStatus.get(getSelectedIndex()))
setChecked(getSelectedIndex(), Boolean.FALSE);
else
setChecked(getSelectedIndex(), Boolean.TRUE);
return Result.HANDLED;
}
return super.handleKeyStroke(keyStroke);
}
/**
* Default renderer for this component which is used unless overridden. The checked state is drawn on the left side
* of the item label using a "[ ]" block filled with an X if the item has checked state on
* @param <V> Type of items in the {@link CheckBoxList}
*/
public static class CheckBoxListItemRenderer<V> extends ListItemRenderer<V,CheckBoxList<V>> {
@Override
public int getHotSpotPositionOnLine(int selectedIndex) {
return 1;
}
@Override
public String getLabel(CheckBoxList<V> listBox, int index, V item) {
String check = " ";
List<Boolean> itemStatus = listBox.itemStatus;
if(itemStatus.get(index))
check = "x";
String text = item.toString();
return "[" + check + "] " + text;
}
@Override
public void drawItem(TextGUIGraphics graphics, CheckBoxList<V> listBox, int index, V item, boolean selected, boolean focused) {
ThemeDefinition themeDefinition = listBox.getTheme().getDefinition(CheckBoxList.class);
ThemeStyle itemStyle;
if(selected && !focused) {
itemStyle = themeDefinition.getSelected();
}
else if(selected) {
itemStyle = themeDefinition.getActive();
}
else if(focused) {
itemStyle = themeDefinition.getInsensitive();
}
else {
itemStyle = themeDefinition.getNormal();
}
if(themeDefinition.getBooleanProperty("CLEAR_WITH_NORMAL", false)) {
graphics.applyThemeStyle(themeDefinition.getNormal());
graphics.fill(' ');
graphics.applyThemeStyle(itemStyle);
}
else {
graphics.applyThemeStyle(itemStyle);
graphics.fill(' ');
}
String brackets = themeDefinition.getCharacter("LEFT_BRACKET", '[') +
" " +
themeDefinition.getCharacter("RIGHT_BRACKET", ']');
if(themeDefinition.getBooleanProperty("FIXED_BRACKET_COLOR", false)) {
graphics.applyThemeStyle(themeDefinition.getPreLight());
graphics.putString(0, 0, brackets);
graphics.applyThemeStyle(itemStyle);
}
else {
graphics.putString(0, 0, brackets);
}
String text = (item != null ? item : "<null>").toString();
graphics.putString(4, 0, text);
boolean itemChecked = listBox.isChecked(index);
char marker = themeDefinition.getCharacter("MARKER", 'x');
if(themeDefinition.getBooleanProperty("MARKER_WITH_NORMAL", false)) {
graphics.applyThemeStyle(themeDefinition.getNormal());
}
if(selected && focused && themeDefinition.getBooleanProperty("HOTSPOT_PRELIGHT", false)) {
graphics.applyThemeStyle(themeDefinition.getPreLight());
}
graphics.setCharacter(1, 0, (itemChecked ? marker : ' '));
}
}
}