| 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.TerminalSize; |
| 22 | |
| 23 | import java.lang.ref.WeakReference; |
| 24 | import java.util.*; |
| 25 | |
| 26 | /** |
| 27 | * This is a special label that contains not just a single text to display but a number of frames that are cycled |
| 28 | * through. The class will manage a timer on its own and ensure the label is updated and redrawn. There is a static |
| 29 | * helper method available to create the classic "spinning bar": {@code createClassicSpinningLine()} |
| 30 | */ |
| 31 | public class AnimatedLabel extends Label { |
| 32 | private static Timer TIMER = null; |
| 33 | private static final WeakHashMap<AnimatedLabel, TimerTask> SCHEDULED_TASKS = new WeakHashMap<AnimatedLabel, TimerTask>(); |
| 34 | |
| 35 | /** |
| 36 | * Creates a classic spinning bar which can be used to signal to the user that an operation in is process. |
| 37 | * @return {@code AnimatedLabel} instance which is setup to show a spinning bar |
| 38 | */ |
| 39 | public static AnimatedLabel createClassicSpinningLine() { |
| 40 | return createClassicSpinningLine(150); |
| 41 | } |
| 42 | |
| 43 | /** |
| 44 | * Creates a classic spinning bar which can be used to signal to the user that an operation in is process. |
| 45 | * @param speed Delay in between each frame |
| 46 | * @return {@code AnimatedLabel} instance which is setup to show a spinning bar |
| 47 | */ |
| 48 | public static AnimatedLabel createClassicSpinningLine(int speed) { |
| 49 | AnimatedLabel animatedLabel = new AnimatedLabel("-"); |
| 50 | animatedLabel.addFrame("\\"); |
| 51 | animatedLabel.addFrame("|"); |
| 52 | animatedLabel.addFrame("/"); |
| 53 | animatedLabel.startAnimation(speed); |
| 54 | return animatedLabel; |
| 55 | } |
| 56 | |
| 57 | private final List<String[]> frames; |
| 58 | private TerminalSize combinedMaximumPreferredSize; |
| 59 | private int currentFrame; |
| 60 | |
| 61 | /** |
| 62 | * Creates a new animated label, initially set to one frame. You will need to add more frames and call |
| 63 | * {@code startAnimation()} for this to start moving. |
| 64 | * |
| 65 | * @param firstFrameText The content of the label at the first frame |
| 66 | */ |
| 67 | public AnimatedLabel(String firstFrameText) { |
| 68 | super(firstFrameText); |
| 69 | frames = new ArrayList<String[]>(); |
| 70 | currentFrame = 0; |
| 71 | combinedMaximumPreferredSize = TerminalSize.ZERO; |
| 72 | |
| 73 | String[] lines = splitIntoMultipleLines(firstFrameText); |
| 74 | frames.add(lines); |
| 75 | ensurePreferredSize(lines); |
| 76 | } |
| 77 | |
| 78 | /** |
| 79 | * Adds one more frame at the end of the list of frames |
| 80 | * @param text Text to use for the label at this frame |
| 81 | */ |
| 82 | public synchronized void addFrame(String text) { |
| 83 | String[] lines = splitIntoMultipleLines(text); |
| 84 | frames.add(lines); |
| 85 | ensurePreferredSize(lines); |
| 86 | } |
| 87 | |
| 88 | private void ensurePreferredSize(String[] lines) { |
| 89 | combinedMaximumPreferredSize = combinedMaximumPreferredSize.max(getBounds(lines, combinedMaximumPreferredSize)); |
| 90 | } |
| 91 | |
| 92 | /** |
| 93 | * Advances the animated label to the next frame. You normally don't need to call this manually as it will be done |
| 94 | * by the animation thread. |
| 95 | */ |
| 96 | public synchronized void nextFrame() { |
| 97 | currentFrame++; |
| 98 | if(currentFrame >= frames.size()) { |
| 99 | currentFrame = 0; |
| 100 | } |
| 101 | super.setLines(frames.get(currentFrame)); |
| 102 | invalidate(); |
| 103 | } |
| 104 | |
| 105 | @Override |
| 106 | public void onRemoved(Container container) { |
| 107 | stopAnimation(); |
| 108 | } |
| 109 | |
| 110 | /** |
| 111 | * Starts the animation thread which will periodically call {@code nextFrame()} at the interval specified by the |
| 112 | * {@code millisecondsPerFrame} parameter. After all frames have been cycled through, it will start over from the |
| 113 | * first frame again. |
| 114 | * @param millisecondsPerFrame The interval in between every frame |
| 115 | */ |
| 116 | public synchronized void startAnimation(long millisecondsPerFrame) { |
| 117 | if(TIMER == null) { |
| 118 | TIMER = new Timer("AnimatedLabel"); |
| 119 | } |
| 120 | AnimationTimerTask animationTimerTask = new AnimationTimerTask(this); |
| 121 | SCHEDULED_TASKS.put(this, animationTimerTask); |
| 122 | TIMER.scheduleAtFixedRate(animationTimerTask, millisecondsPerFrame, millisecondsPerFrame); |
| 123 | } |
| 124 | |
| 125 | /** |
| 126 | * Halts the animation thread and the label will stop at whatever was the current frame at the time when this was |
| 127 | * called |
| 128 | */ |
| 129 | public synchronized void stopAnimation() { |
| 130 | removeTaskFromTimer(this); |
| 131 | } |
| 132 | |
| 133 | private static synchronized void removeTaskFromTimer(AnimatedLabel animatedLabel) { |
| 134 | SCHEDULED_TASKS.get(animatedLabel).cancel(); |
| 135 | SCHEDULED_TASKS.remove(animatedLabel); |
| 136 | canCloseTimer(); |
| 137 | } |
| 138 | |
| 139 | private static synchronized void canCloseTimer() { |
| 140 | if(SCHEDULED_TASKS.isEmpty()) { |
| 141 | TIMER.cancel(); |
| 142 | TIMER = null; |
| 143 | } |
| 144 | } |
| 145 | |
| 146 | private static class AnimationTimerTask extends TimerTask { |
| 147 | private final WeakReference<AnimatedLabel> labelRef; |
| 148 | |
| 149 | private AnimationTimerTask(AnimatedLabel label) { |
| 150 | this.labelRef = new WeakReference<AnimatedLabel>(label); |
| 151 | } |
| 152 | |
| 153 | @Override |
| 154 | public void run() { |
| 155 | AnimatedLabel animatedLabel = labelRef.get(); |
| 156 | if(animatedLabel == null) { |
| 157 | cancel(); |
| 158 | canCloseTimer(); |
| 159 | } |
| 160 | else { |
| 161 | if(animatedLabel.getBasePane() == null) { |
| 162 | animatedLabel.stopAnimation(); |
| 163 | } |
| 164 | else { |
| 165 | animatedLabel.nextFrame(); |
| 166 | } |
| 167 | } |
| 168 | } |
| 169 | } |
| 170 | } |