| 1 | /* |
| 2 | * This file is part of lanterna (http://code.google.com/p/lanterna/). |
| 3 | * |
| 4 | * lanterna is free software: you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU Lesser General Public License as published by |
| 6 | * the Free Software Foundation, either version 3 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public License |
| 15 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 16 | * |
| 17 | * Copyright (C) 2010-2015 Martin |
| 18 | */ |
| 19 | package com.googlecode.lanterna.gui2; |
| 20 | |
| 21 | import com.googlecode.lanterna.TerminalPosition; |
| 22 | import com.googlecode.lanterna.TerminalSize; |
| 23 | |
| 24 | import java.util.*; |
| 25 | |
| 26 | /** |
| 27 | * BorderLayout imitates the BorderLayout class from AWT, allowing you to add a center component with optional |
| 28 | * components around it in top, bottom, left and right locations. The edge components will be sized at their preferred |
| 29 | * size and the center component will take up whatever remains. |
| 30 | * @author martin |
| 31 | */ |
| 32 | public class BorderLayout implements LayoutManager { |
| 33 | |
| 34 | /** |
| 35 | * This type is what you use as the layout data for components added to a panel using {@code BorderLayout} for its |
| 36 | * layout manager. This values specified where inside the panel the component should be added. |
| 37 | */ |
| 38 | public enum Location implements LayoutData { |
| 39 | /** |
| 40 | * The component with this value as its layout data will occupy the center space, whatever is remaining after |
| 41 | * the other components (if any) have allocated their space. |
| 42 | */ |
| 43 | CENTER, |
| 44 | /** |
| 45 | * The component with this value as its layout data will occupy the left side of the container, attempting to |
| 46 | * allocate the preferred width of the component and at least the preferred height, but could be more depending |
| 47 | * on the other components added. |
| 48 | */ |
| 49 | LEFT, |
| 50 | /** |
| 51 | * The component with this value as its layout data will occupy the right side of the container, attempting to |
| 52 | * allocate the preferred width of the component and at least the preferred height, but could be more depending |
| 53 | * on the other components added. |
| 54 | */ |
| 55 | RIGHT, |
| 56 | /** |
| 57 | * The component with this value as its layout data will occupy the top side of the container, attempting to |
| 58 | * allocate the preferred height of the component and at least the preferred width, but could be more depending |
| 59 | * on the other components added. |
| 60 | */ |
| 61 | TOP, |
| 62 | /** |
| 63 | * The component with this value as its layout data will occupy the bottom side of the container, attempting to |
| 64 | * allocate the preferred height of the component and at least the preferred width, but could be more depending |
| 65 | * on the other components added. |
| 66 | */ |
| 67 | BOTTOM, |
| 68 | ; |
| 69 | } |
| 70 | |
| 71 | //When components don't have a location, we'll assign an available location based on this order |
| 72 | private static final List<Location> AUTO_ASSIGN_ORDER = Collections.unmodifiableList(Arrays.asList( |
| 73 | Location.CENTER, |
| 74 | Location.TOP, |
| 75 | Location.BOTTOM, |
| 76 | Location.LEFT, |
| 77 | Location.RIGHT)); |
| 78 | |
| 79 | @Override |
| 80 | public TerminalSize getPreferredSize(List<Component> components) { |
| 81 | EnumMap<Location, Component> layout = makeLookupMap(components); |
| 82 | int preferredHeight = |
| 83 | (layout.containsKey(Location.TOP) ? layout.get(Location.TOP).getPreferredSize().getRows() : 0) |
| 84 | + |
| 85 | Math.max( |
| 86 | layout.containsKey(Location.LEFT) ? layout.get(Location.LEFT).getPreferredSize().getRows() : 0, |
| 87 | Math.max( |
| 88 | layout.containsKey(Location.CENTER) ? layout.get(Location.CENTER).getPreferredSize().getRows() : 0, |
| 89 | layout.containsKey(Location.RIGHT) ? layout.get(Location.RIGHT).getPreferredSize().getRows() : 0)) |
| 90 | + |
| 91 | (layout.containsKey(Location.BOTTOM) ? layout.get(Location.BOTTOM).getPreferredSize().getRows() : 0); |
| 92 | |
| 93 | int preferredWidth = |
| 94 | Math.max( |
| 95 | (layout.containsKey(Location.LEFT) ? layout.get(Location.LEFT).getPreferredSize().getColumns() : 0) + |
| 96 | (layout.containsKey(Location.CENTER) ? layout.get(Location.CENTER).getPreferredSize().getColumns() : 0) + |
| 97 | (layout.containsKey(Location.RIGHT) ? layout.get(Location.RIGHT).getPreferredSize().getColumns() : 0), |
| 98 | Math.max( |
| 99 | layout.containsKey(Location.TOP) ? layout.get(Location.TOP).getPreferredSize().getColumns() : 0, |
| 100 | layout.containsKey(Location.BOTTOM) ? layout.get(Location.BOTTOM).getPreferredSize().getColumns() : 0)); |
| 101 | return new TerminalSize(preferredWidth, preferredHeight); |
| 102 | } |
| 103 | |
| 104 | @Override |
| 105 | public void doLayout(TerminalSize area, List<Component> components) { |
| 106 | EnumMap<Location, Component> layout = makeLookupMap(components); |
| 107 | int availableHorizontalSpace = area.getColumns(); |
| 108 | int availableVerticalSpace = area.getRows(); |
| 109 | |
| 110 | //We'll need this later on |
| 111 | int topComponentHeight = 0; |
| 112 | int leftComponentWidth = 0; |
| 113 | |
| 114 | //First allocate the top |
| 115 | if(layout.containsKey(Location.TOP)) { |
| 116 | Component topComponent = layout.get(Location.TOP); |
| 117 | topComponentHeight = Math.min(topComponent.getPreferredSize().getRows(), availableVerticalSpace); |
| 118 | topComponent.setPosition(TerminalPosition.TOP_LEFT_CORNER); |
| 119 | topComponent.setSize(new TerminalSize(availableHorizontalSpace, topComponentHeight)); |
| 120 | availableVerticalSpace -= topComponentHeight; |
| 121 | } |
| 122 | |
| 123 | //Next allocate the bottom |
| 124 | if(layout.containsKey(Location.BOTTOM)) { |
| 125 | Component bottomComponent = layout.get(Location.BOTTOM); |
| 126 | int bottomComponentHeight = Math.min(bottomComponent.getPreferredSize().getRows(), availableVerticalSpace); |
| 127 | bottomComponent.setPosition(new TerminalPosition(0, area.getRows() - bottomComponentHeight)); |
| 128 | bottomComponent.setSize(new TerminalSize(availableHorizontalSpace, bottomComponentHeight)); |
| 129 | availableVerticalSpace -= bottomComponentHeight; |
| 130 | } |
| 131 | |
| 132 | //Now divide the remaining space between LEFT, CENTER and RIGHT |
| 133 | if(layout.containsKey(Location.LEFT)) { |
| 134 | Component leftComponent = layout.get(Location.LEFT); |
| 135 | leftComponentWidth = Math.min(leftComponent.getPreferredSize().getColumns(), availableHorizontalSpace); |
| 136 | leftComponent.setPosition(new TerminalPosition(0, topComponentHeight)); |
| 137 | leftComponent.setSize(new TerminalSize(leftComponentWidth, availableVerticalSpace)); |
| 138 | availableHorizontalSpace -= leftComponentWidth; |
| 139 | } |
| 140 | if(layout.containsKey(Location.RIGHT)) { |
| 141 | Component rightComponent = layout.get(Location.RIGHT); |
| 142 | int rightComponentWidth = Math.min(rightComponent.getPreferredSize().getColumns(), availableHorizontalSpace); |
| 143 | rightComponent.setPosition(new TerminalPosition(area.getColumns() - rightComponentWidth, topComponentHeight)); |
| 144 | rightComponent.setSize(new TerminalSize(rightComponentWidth, availableVerticalSpace)); |
| 145 | availableHorizontalSpace -= rightComponentWidth; |
| 146 | } |
| 147 | if(layout.containsKey(Location.CENTER)) { |
| 148 | Component centerComponent = layout.get(Location.CENTER); |
| 149 | centerComponent.setPosition(new TerminalPosition(leftComponentWidth, topComponentHeight)); |
| 150 | centerComponent.setSize(new TerminalSize(availableHorizontalSpace, availableVerticalSpace)); |
| 151 | } |
| 152 | |
| 153 | //Set the remaining components to 0x0 |
| 154 | for(Component component: components) { |
| 155 | if(!layout.values().contains(component)) { |
| 156 | component.setPosition(TerminalPosition.TOP_LEFT_CORNER); |
| 157 | component.setSize(TerminalSize.ZERO); |
| 158 | } |
| 159 | } |
| 160 | } |
| 161 | |
| 162 | private EnumMap<Location, Component> makeLookupMap(List<Component> components) { |
| 163 | EnumMap<Location, Component> map = new EnumMap<BorderLayout.Location, Component>(Location.class); |
| 164 | List<Component> unassignedComponents = new ArrayList<Component>(); |
| 165 | for(Component component: components) { |
| 166 | if(component.getLayoutData() instanceof Location) { |
| 167 | map.put((Location)component.getLayoutData(), component); |
| 168 | } |
| 169 | else { |
| 170 | unassignedComponents.add(component); |
| 171 | } |
| 172 | } |
| 173 | //Try to assign components to available locations |
| 174 | for(Component component: unassignedComponents) { |
| 175 | for(Location location: AUTO_ASSIGN_ORDER) { |
| 176 | if(!map.containsKey(location)) { |
| 177 | map.put(location, component); |
| 178 | break; |
| 179 | } |
| 180 | } |
| 181 | } |
| 182 | return map; |
| 183 | } |
| 184 | |
| 185 | @Override |
| 186 | public boolean hasChanged() { |
| 187 | //No internal state |
| 188 | return false; |
| 189 | } |
| 190 | } |