| 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.input.KeyStroke; |
| 23 | |
| 24 | /** |
| 25 | * Default implementation of Interactable that extends from AbstractComponent. If you want to write your own component |
| 26 | * that is interactable, i.e. can receive keyboard (and mouse) input, you probably want to extend from this class as |
| 27 | * it contains some common implementations of the methods from {@code Interactable} interface |
| 28 | * @param <T> Should always be itself, see {@code AbstractComponent} |
| 29 | * @author Martin |
| 30 | */ |
| 31 | public abstract class AbstractInteractableComponent<T extends AbstractInteractableComponent<T>> extends AbstractComponent<T> implements Interactable { |
| 32 | |
| 33 | private InputFilter inputFilter; |
| 34 | private boolean inFocus; |
| 35 | |
| 36 | /** |
| 37 | * Default constructor |
| 38 | */ |
| 39 | protected AbstractInteractableComponent() { |
| 40 | inputFilter = null; |
| 41 | inFocus = false; |
| 42 | } |
| 43 | |
| 44 | @Override |
| 45 | public T takeFocus() { |
| 46 | BasePane basePane = getBasePane(); |
| 47 | if(basePane != null) { |
| 48 | basePane.setFocusedInteractable(this); |
| 49 | } |
| 50 | return self(); |
| 51 | } |
| 52 | |
| 53 | /** |
| 54 | * {@inheritDoc} |
| 55 | * <p> |
| 56 | * This method is final in {@code AbstractInteractableComponent}, please override {@code afterEnterFocus} instead |
| 57 | */ |
| 58 | @Override |
| 59 | public final void onEnterFocus(FocusChangeDirection direction, Interactable previouslyInFocus) { |
| 60 | inFocus = true; |
| 61 | afterEnterFocus(direction, previouslyInFocus); |
| 62 | } |
| 63 | |
| 64 | /** |
| 65 | * Called by {@code AbstractInteractableComponent} automatically after this component has received input focus. You |
| 66 | * can override this method if you need to trigger some action based on this. |
| 67 | * @param direction How focus was transferred, keep in mind this is from the previous component's point of view so |
| 68 | * if this parameter has value DOWN, focus came in from above |
| 69 | * @param previouslyInFocus Which interactable component had focus previously |
| 70 | */ |
| 71 | @SuppressWarnings("EmptyMethod") |
| 72 | protected void afterEnterFocus(FocusChangeDirection direction, Interactable previouslyInFocus) { |
| 73 | //By default no action |
| 74 | } |
| 75 | |
| 76 | /** |
| 77 | * {@inheritDoc} |
| 78 | * <p> |
| 79 | * This method is final in {@code AbstractInteractableComponent}, please override {@code afterLeaveFocus} instead |
| 80 | */ |
| 81 | @Override |
| 82 | public final void onLeaveFocus(FocusChangeDirection direction, Interactable nextInFocus) { |
| 83 | inFocus = false; |
| 84 | afterLeaveFocus(direction, nextInFocus); |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * Called by {@code AbstractInteractableComponent} automatically after this component has lost input focus. You |
| 89 | * can override this method if you need to trigger some action based on this. |
| 90 | * @param direction How focus was transferred, keep in mind this is from the this component's point of view so |
| 91 | * if this parameter has value DOWN, focus is moving down to a component below |
| 92 | * @param nextInFocus Which interactable component is going to receive focus |
| 93 | */ |
| 94 | @SuppressWarnings("EmptyMethod") |
| 95 | protected void afterLeaveFocus(FocusChangeDirection direction, Interactable nextInFocus) { |
| 96 | //By default no action |
| 97 | } |
| 98 | |
| 99 | @Override |
| 100 | protected abstract InteractableRenderer<T> createDefaultRenderer(); |
| 101 | |
| 102 | @Override |
| 103 | public InteractableRenderer<T> getRenderer() { |
| 104 | return (InteractableRenderer<T>)super.getRenderer(); |
| 105 | } |
| 106 | |
| 107 | @Override |
| 108 | public boolean isFocused() { |
| 109 | return inFocus; |
| 110 | } |
| 111 | |
| 112 | @Override |
| 113 | public final synchronized Result handleInput(KeyStroke keyStroke) { |
| 114 | if(inputFilter == null || inputFilter.onInput(this, keyStroke)) { |
| 115 | return handleKeyStroke(keyStroke); |
| 116 | } |
| 117 | else { |
| 118 | return Result.UNHANDLED; |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | /** |
| 123 | * This method can be overridden to handle various user input (mostly from the keyboard) when this component is in |
| 124 | * focus. The input method from the interface, {@code handleInput(..)} is final in |
| 125 | * {@code AbstractInteractableComponent} to ensure the input filter is properly handled. If the filter decides that |
| 126 | * this event should be processed, it will call this method. |
| 127 | * @param keyStroke What input was entered by the user |
| 128 | * @return Result of processing the key-stroke |
| 129 | */ |
| 130 | protected Result handleKeyStroke(KeyStroke keyStroke) { |
| 131 | // Skip the keystroke if ctrl, alt or shift was down |
| 132 | if(!keyStroke.isAltDown() && !keyStroke.isCtrlDown() && !keyStroke.isShiftDown()) { |
| 133 | switch(keyStroke.getKeyType()) { |
| 134 | case ArrowDown: |
| 135 | return Result.MOVE_FOCUS_DOWN; |
| 136 | case ArrowLeft: |
| 137 | return Result.MOVE_FOCUS_LEFT; |
| 138 | case ArrowRight: |
| 139 | return Result.MOVE_FOCUS_RIGHT; |
| 140 | case ArrowUp: |
| 141 | return Result.MOVE_FOCUS_UP; |
| 142 | case Tab: |
| 143 | return Result.MOVE_FOCUS_NEXT; |
| 144 | case ReverseTab: |
| 145 | return Result.MOVE_FOCUS_PREVIOUS; |
| 146 | case MouseEvent: |
| 147 | getBasePane().setFocusedInteractable(this); |
| 148 | return Result.HANDLED; |
| 149 | default: |
| 150 | } |
| 151 | } |
| 152 | return Result.UNHANDLED; |
| 153 | } |
| 154 | |
| 155 | @Override |
| 156 | public TerminalPosition getCursorLocation() { |
| 157 | return getRenderer().getCursorLocation(self()); |
| 158 | } |
| 159 | |
| 160 | @Override |
| 161 | public InputFilter getInputFilter() { |
| 162 | return inputFilter; |
| 163 | } |
| 164 | |
| 165 | @Override |
| 166 | public synchronized T setInputFilter(InputFilter inputFilter) { |
| 167 | this.inputFilter = inputFilter; |
| 168 | return self(); |
| 169 | } |
| 170 | } |