Java tutorial
/* * Copyright 2014-2016 See AUTHORS file. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.kotcrab.vis.ui.widget; import com.badlogic.gdx.graphics.Color; import com.badlogic.gdx.graphics.g2d.Batch; import com.badlogic.gdx.graphics.g2d.BitmapFont; import com.badlogic.gdx.graphics.g2d.GlyphLayout; import com.badlogic.gdx.scenes.scene2d.ui.ScrollPane; import com.badlogic.gdx.utils.Array; import com.badlogic.gdx.utils.Pool; import com.badlogic.gdx.utils.Pools; import com.kotcrab.vis.ui.util.highlight.BaseHighlighter; import com.kotcrab.vis.ui.util.highlight.Highlight; import com.kotcrab.vis.ui.util.highlight.Highlighter; /** * Text area implementation supporting highlighting words and scrolling in both X and Y directions. * <p> * For best scroll pane settings you should create scroll pane using {@link #createCompatibleScrollPane()}. * <p> * Note about overlapping highlights: this text area can handle overlapping highlights, highlights that starts earlier * have higher priority. If two highlights have the exactly the same start point, then it is undefined which highlight * will be used and depends on how array containing highlights will be sorted. * @author Kotcrab * @see Highlighter * @since 1.1.2 */ public class HighlightTextArea extends ScrollableTextArea { private Array<Highlight> highlights = new Array<Highlight>(); private Array<Chunk> renderChunks = new Array<Chunk>(); private boolean chunkUpdateScheduled = true; private Color defaultColor = Color.WHITE; private BaseHighlighter highlighter; private float maxAreaWidth = 0; private float maxAreaHeight = 0; public HighlightTextArea(String text) { super(text); softwrap = false; } public HighlightTextArea(String text, String styleName) { super(text, styleName); } public HighlightTextArea(String text, VisTextFieldStyle style) { super(text, style); } @Override void updateDisplayText() { super.updateDisplayText(); processHighlighter(); } @Override protected void calculateOffsets() { super.calculateOffsets(); if (chunkUpdateScheduled == false) return; chunkUpdateScheduled = false; highlights.sort(); renderChunks.clear(); String text = getText(); Pool<GlyphLayout> layoutPool = Pools.get(GlyphLayout.class); GlyphLayout layout = layoutPool.obtain(); boolean carryHighlight = false; for (int lineIdx = 0, highlightIdx = 0; lineIdx < linesBreak.size; lineIdx += 2) { int lineStart = linesBreak.items[lineIdx]; int lineEnd = linesBreak.items[lineIdx + 1]; int lineProgress = lineStart; float chunkOffset = 0; for (; highlightIdx < highlights.size;) { Highlight highlight = highlights.get(highlightIdx); if (highlight.getStart() > lineEnd) { break; } if (highlight.getStart() == lineProgress || carryHighlight) { renderChunks.add(new Chunk(text.substring(lineProgress, Math.min(highlight.getEnd(), lineEnd)), highlight.getColor(), chunkOffset, lineIdx)); lineProgress = Math.min(highlight.getEnd(), lineEnd); if (highlight.getEnd() > lineEnd) { carryHighlight = true; } else { carryHighlight = false; highlightIdx++; } } else { //protect against overlapping highlights boolean noMatch = false; while (highlight.getStart() <= lineProgress) { highlightIdx++; if (highlightIdx >= highlights.size) { noMatch = true; break; } highlight = highlights.get(highlightIdx); if (highlight.getStart() > lineEnd) { noMatch = true; break; } } if (noMatch) break; renderChunks.add(new Chunk(text.substring(lineProgress, highlight.getStart()), defaultColor, chunkOffset, lineIdx)); lineProgress = highlight.getStart(); } Chunk chunk = renderChunks.peek(); layout.setText(style.font, chunk.text); chunkOffset += layout.width; //current highlight needs to be applied to next line meaning that there is no other highlights that can be applied to currently parsed line if (carryHighlight) break; } if (lineProgress < lineEnd) { renderChunks .add(new Chunk(text.substring(lineProgress, lineEnd), defaultColor, chunkOffset, lineIdx)); } } maxAreaWidth = 0; for (String line : text.split("\\n")) { layout.setText(style.font, line); maxAreaWidth = Math.max(maxAreaWidth, layout.width + 30); } layoutPool.free(layout); updateScrollLayout(); } @Override protected void drawText(Batch batch, BitmapFont font, float x, float y) { maxAreaHeight = 0; float offsetY = 0; for (int i = firstLineShowing * 2; i < (firstLineShowing + linesShowing) * 2 && i < linesBreak.size; i += 2) { for (Chunk chunk : renderChunks) { if (chunk.lineIndex == i) { font.setColor(chunk.color); font.draw(batch, chunk.text, x + chunk.offsetX, y + offsetY); } } offsetY -= font.getLineHeight(); maxAreaHeight += font.getLineHeight(); } maxAreaHeight += 30; } /** * Processes highlighter rules, collects created highlights and schedules text area displayed text update. This should be called * after highlighter rules has changed to update highlights. */ public void processHighlighter() { if (highlights == null) return; highlights.clear(); if (highlighter != null) highlighter.process(this, highlights); chunkUpdateScheduled = true; } /** * Changes highlighter of text area. Note that you don't have to call {@link #processHighlighter()} after changing * highlighter - you only have to call it when highlighter rules has changed. */ public void setHighlighter(BaseHighlighter highlighter) { this.highlighter = highlighter; processHighlighter(); } public BaseHighlighter getHighlighter() { return highlighter; } @Override public float getPrefWidth() { return maxAreaWidth + 5; } @Override public float getPrefHeight() { return maxAreaHeight + 5; } @Override public ScrollPane createCompatibleScrollPane() { ScrollPane scrollPane = super.createCompatibleScrollPane(); scrollPane.setScrollingDisabled(false, false); return scrollPane; } private static class Chunk { String text; Color color; float offsetX; int lineIndex; public Chunk(String text, Color color, float offsetX, int lineIndex) { this.text = text; this.color = color; this.offsetX = offsetX; this.lineIndex = lineIndex; } } }