1 /*
2 * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package javafx.scene.text;
27
28 import java.util.ArrayList;
29 import java.util.Collections;
30 import java.util.List;
31 import javafx.beans.property.DoubleProperty;
32 import javafx.beans.property.ObjectProperty;
33 import javafx.geometry.HPos;
34 import javafx.geometry.Insets;
35 import javafx.geometry.NodeOrientation;
36 import javafx.geometry.Orientation;
37 import javafx.geometry.VPos;
38 import javafx.scene.AccessibleAttribute;
39 import javafx.scene.AccessibleRole;
40 import javafx.scene.Node;
41 import javafx.scene.layout.Pane;
42 import javafx.scene.shape.PathElement;
43 import javafx.css.StyleableDoubleProperty;
44 import javafx.css.StyleableObjectProperty;
45 import javafx.css.CssMetaData;
46 import javafx.css.converter.EnumConverter;
47 import javafx.css.converter.SizeConverter;
48 import com.sun.javafx.geom.BaseBounds;
49 import com.sun.javafx.geom.Point2D;
50 import com.sun.javafx.geom.RectBounds;
51 import com.sun.javafx.scene.text.GlyphList;
52 import com.sun.javafx.scene.text.TextLayout;
53 import com.sun.javafx.scene.text.TextLayoutFactory;
54 import com.sun.javafx.scene.text.TextSpan;
55 import com.sun.javafx.tk.Toolkit;
56 import javafx.css.Styleable;
57 import javafx.css.StyleableProperty;
58
59 /**
60 * TextFlow is special layout designed to lay out rich text.
61 * It can be used to layout several {@link Text} nodes in a single text flow.
62 * The TextFlow uses the text and the font of each {@link Text} node inside of it
63 * plus it own width and text alignment to determine the location for each child.
64 * A single {@link Text} node can span over several lines due to wrapping and
65 * the visual location of {@link Text} node can differ from the logical location
66 * due to bidi reordering.
67 *
68 * <p>
69 * Any other Node, rather than Text, will be treated as embedded object in the
70 * text layout. It will be inserted in the content using its preferred width,
71 * height, and baseline offset.
72 *
73 * <p>
74 * When a {@link Text} node is inside of a TextFlow some its properties are ignored.
75 * For example, the x and y properties of the {@link Text} node are ignored since
76 * the location of the node is determined by the parent. Likewise, the wrapping
77 * width in the {@link Text} node is ignored since the width used for wrapping
78 * is the TextFlow's width. The value of the <code>pickOnBounds</code> property
79 * of a {@link Text} is set to <code>false</code> when it is laid out by the
80 * TextFlow. This happens because the content of a single {@link Text} node can
81 * divided and placed in the different locations on the TextFlow (usually due to
82 * line breaking and bidi reordering).
83 *
84 * <p>
85 * The wrapping width of the layout is determined by the region's current width.
86 * It can be specified by the application by setting the textflow's preferred
87 * width. If no wrapping is desired, the application can either set the preferred
88 * with to Double.MAX_VALUE or Region.USE_COMPUTED_SIZE.
89 *
90 * <p>
91 * Paragraphs are separated by {@code '\n'} present in any Text child.
92 *
93 * <p>
94 * Example of a TextFlow:
95 * <pre><code>
96 * Text text1 = new Text("Big italic red text");
97 * text1.setFill(Color.RED);
98 * text1.setFont(Font.font("Helvetica", FontPosture.ITALIC, 40));
99 * Text text2 = new Text(" little bold blue text");
100 * text2.setFill(Color.BLUE);
101 * text2.setFont(Font.font("Helvetica", FontWeight.BOLD, 10));
102 * TextFlow textFlow = new TextFlow(text1, text2);
103 * </code></pre>
104 *
105 * <p>
106 * TextFlow lays out each managed child regardless of the child's visible property value;
107 * unmanaged children are ignored for all layout calculations.</p>
108 *
109 * <p>
110 * TextFlow may be styled with backgrounds and borders using CSS. See
111 * {@link javafx.scene.layout.Region Region} superclass for details.</p>
112 *
113 * <h4>Resizable Range</h4>
114 *
115 * A textflow's parent will resize the textflow within the textflow's range
116 * during layout. By default the textflow computes this range based on its content
117 * as outlined in the tables below.
118 * <p>
119 * <table border="1">
120 * <tr><td></td><th>width</th><th>height</th></tr>
121 * <tr><th>minimum</th>
122 * <td>left/right insets</td>
123 * <td>top/bottom insets plus the height of the text content</td></tr>
124 * <tr><th>preferred</th>
125 * <td>left/right insets plus the width of the text content</td>
126 * <td>top/bottom insets plus the height of the text content</td></tr>
127 * <tr><th>maximum</th>
128 * <td>Double.MAX_VALUE</td><td>Double.MAX_VALUE</td></tr>
129 * </table>
130 * <p>
131 * A textflow's unbounded maximum width and height are an indication to the parent that
132 * it may be resized beyond its preferred size to fill whatever space is assigned to it.
133 * <p>
134 * TextFlow provides properties for setting the size range directly. These
135 * properties default to the sentinel value Region.USE_COMPUTED_SIZE, however the
136 * application may set them to other values as needed:
137 * <pre><code>
138 * <b>textflow.setMaxWidth(500);</b>
139 * </code></pre>
140 * Applications may restore the computed values by setting these properties back
141 * to Region.USE_COMPUTED_SIZE.
142 * <p>
143 * TextFlow does not clip its content by default, so it is possible that childrens'
144 * bounds may extend outside its own bounds if a child's pref size is larger than
145 * the space textflow has to allocate for it.</p>
146 *
147 * @since JavaFX 8.0
148 */
149 public class TextFlow extends Pane {
150
151 private TextLayout layout;
152 private boolean needsContent;
153 private boolean inLayout;
154 // private static final PathElement[] EMPTY_PATH_ELEMENT_ARRAY = new PathElement[0];
155
156 /**
157 * Creates an empty TextFlow layout.
158 */
159 public TextFlow() {
160 super();
161 effectiveNodeOrientationProperty().addListener(observable -> checkOrientation());
162 setAccessibleRole(AccessibleRole.TEXT);
163 }
164
165 /**
166 * Creates a TextFlow layout with the given children.
167 *
168 * @param children children.
169 */
170 public TextFlow(Node... children) {
171 this();
172 getChildren().addAll(children);
173 }
174
175 private void checkOrientation() {
176 NodeOrientation orientation = getEffectiveNodeOrientation();
177 boolean rtl = orientation == NodeOrientation.RIGHT_TO_LEFT;
178 int dir = rtl ? TextLayout.DIRECTION_RTL : TextLayout.DIRECTION_LTR;
179 TextLayout layout = getTextLayout();
180 if (layout.setDirection(dir)) {
181 requestLayout();
182 }
183 }
184
185 /**
186 * Maps local point to index in the content.
187 *
188 * @since 9
189 */
190 public final HitInfo hitTest(javafx.geometry.Point2D point) {
191 if (point != null) {
192 TextLayout layout = getTextLayout();
193 double x = point.getX()/* - getX()*/;
194 double y = point.getY()/* - getY()/* + getYRendering()*/;
195 TextLayout.Hit layoutHit = layout.getHitInfo((float)x, (float)y);
196 return new HitInfo(layoutHit.getCharIndex(), layoutHit.getInsertionIndex(),
197 layoutHit.isLeading(), null/*getText()*/);
198 } else {
199 return null;
200 }
201 }
202
203 /**
204 * Returns shape of caret in local coordinates.
205 *
206 * @since 9
207 */
208 public PathElement[] caretShape(int charIndex, boolean leading) {
209 return getTextLayout().getCaretShape(charIndex, leading, 0, 0);
210 }
211
212 /**
213 * Returns shape for the range of the text in local coordinates.
214 *
215 * @since 9
216 */
217 public final PathElement[] rangeShape(int start, int end) {
218 return getRange(start, end, TextLayout.TYPE_TEXT);
219 }
220
221 @Override
222 public boolean usesMirroring() {
223 return false;
224 }
225
226 @Override protected void setWidth(double value) {
227 if (value != getWidth()) {
228 TextLayout layout = getTextLayout();
229 Insets insets = getInsets();
230 double left = snapSpace(insets.getLeft());
231 double right = snapSpace(insets.getRight());
232 double width = Math.max(1, value - left - right);
233 layout.setWrapWidth((float)width);
234 super.setWidth(value);
235 }
236 }
237
238 @Override protected double computePrefWidth(double height) {
239 TextLayout layout = getTextLayout();
240 layout.setWrapWidth(0);
241 double width = layout.getBounds().getWidth();
242 Insets insets = getInsets();
243 double left = snapSpace(insets.getLeft());
244 double right = snapSpace(insets.getRight());
245 double wrappingWidth = Math.max(1, getWidth() - left - right);
246 layout.setWrapWidth((float)wrappingWidth);
247 return left + width + right;
248 }
249
250 @Override protected double computePrefHeight(double width) {
251 TextLayout layout = getTextLayout();
252 Insets insets = getInsets();
253 double left = snapSpace(insets.getLeft());
254 double right = snapSpace(insets.getRight());
255 if (width == USE_COMPUTED_SIZE) {
256 layout.setWrapWidth(0);
257 } else {
258 double wrappingWidth = Math.max(1, width - left - right);
259 layout.setWrapWidth((float)wrappingWidth);
260 }
261 double height = layout.getBounds().getHeight();
262 double wrappingWidth = Math.max(1, getWidth() - left - right);
263 layout.setWrapWidth((float)wrappingWidth);
264 double top = snapSpace(insets.getTop());
265 double bottom = snapSpace(insets.getBottom());
266 return top + height + bottom;
267 }
268
269 @Override protected double computeMinHeight(double width) {
270 return computePrefHeight(width);
271 }
272
273 @Override public void requestLayout() {
274 /* The geometry of text nodes can be changed during layout children.
275 * For that reason it has to call impl_geomChanged() causing
276 * requestLayout() to happen during layoutChildren().
277 * The inLayout flag prevents this call to cause any extra work.
278 */
279 if (inLayout) return;
280
281 /*
282 * There is no need to reset the text layout's content every time
283 * requestLayout() is called. For example, the content needs
284 * to be set when:
285 * children add or removed
286 * children managed state changes
287 * children geomChanged (width/height of embedded node)
288 * children content changes (text/font of text node)
289 * The content does not need to set when:
290 * the width/height changes in the region
291 * the insets changes in the region
292 *
293 * Unfortunately, it is not possible to know what change invoked request
294 * layout. The solution is to always reset the content in the text
295 * layout and rely on it to preserve itself if the new content equals to
296 * the old one. The cost to generate the new content is not avoid.
297 */
298 needsContent = true;
299 super.requestLayout();
300 }
301
302 @Override public Orientation getContentBias() {
303 return Orientation.HORIZONTAL;
304 }
305
306 @Override protected void layoutChildren() {
307 inLayout = true;
308 Insets insets = getInsets();
309 double top = snapSpace(insets.getTop());
310 double left = snapSpace(insets.getLeft());
311
312 GlyphList[] runs = getTextLayout().getRuns();
313 for (int j = 0; j < runs.length; j++) {
314 GlyphList run = runs[j];
315 TextSpan span = run.getTextSpan();
316 if (span instanceof EmbeddedSpan) {
317 Node child = ((EmbeddedSpan)span).getNode();
318 Point2D location = run.getLocation();
319 double baselineOffset = -run.getLineBounds().getMinY();
320
321 layoutInArea(child, left + location.x, top + location.y,
322 run.getWidth(), run.getHeight(),
323 baselineOffset, null, true, true,
324 HPos.CENTER, VPos.BASELINE);
325 }
326 }
327
328 List<Node> managed = getManagedChildren();
329 for (Node node: managed) {
330 if (node instanceof Text) {
331 Text text = (Text)node;
332 text.layoutSpan(runs);
333 BaseBounds spanBounds = text.getSpanBounds();
334 text.relocate(left + spanBounds.getMinX(),
335 top + spanBounds.getMinY());
336 }
337 }
338 inLayout = false;
339 }
340
341 private PathElement[] getRange(int start, int end, int type) {
342 TextLayout layout = getTextLayout();
343 // int length = textLayout().getCharCount();
344 // if (0 <= start && start < end && end <= length) {
345 return layout.getRange(start, end, type, 0, 0);
346 // }
347 // return EMPTY_PATH_ELEMENT_ARRAY;
348 }
349
350 private static class EmbeddedSpan implements TextSpan {
351 RectBounds bounds;
352 Node node;
353 public EmbeddedSpan(Node node, double baseline, double width, double height) {
354 this.node = node;
355 bounds = new RectBounds(0, (float)-baseline,
356 (float)width, (float)(height - baseline));
357 }
358
359 @Override public String getText() {
360 return "\uFFFC";
361 }
362
363 @Override public Object getFont() {
364 return null;
365 }
366
367 @Override public RectBounds getBounds() {
368 return bounds;
369 }
370
371 public Node getNode() {
372 return node;
373 }
374 }
375
376 TextLayout getTextLayout() {
377 if (layout == null) {
378 TextLayoutFactory factory = Toolkit.getToolkit().getTextLayoutFactory();
379 layout = factory.createLayout();
380 needsContent = true;
381 }
382 if (needsContent) {
383 List<Node> children = getManagedChildren();
384 TextSpan[] spans = new TextSpan[children.size()];
385 for (int i = 0; i < spans.length; i++) {
386 Node node = children.get(i);
387 if (node instanceof Text) {
388 spans[i] = ((Text)node).getTextSpan();
389 } else {
390 /* Creating a text span every time forces text layout
391 * to run a full text analysis in the new content.
392 */
393 double baseline = node.getBaselineOffset();
394 if (baseline == BASELINE_OFFSET_SAME_AS_HEIGHT) {
395 baseline = node.getLayoutBounds().getHeight();
396 }
397 double width = computeChildPrefAreaWidth(node, null);
398 double height = computeChildPrefAreaHeight(node, null);
399 spans[i] = new EmbeddedSpan(node, baseline, width, height);
400 }
401 }
402 layout.setContent(spans);
403 needsContent = false;
404 }
405 return layout;
406 }
407
408 /**
409 * Defines horizontal text alignment.
410 *
411 * @defaultValue TextAlignment.LEFT
412 */
413 private ObjectProperty<TextAlignment> textAlignment;
414
415 public final void setTextAlignment(TextAlignment value) {
416 textAlignmentProperty().set(value);
417 }
418
419 public final TextAlignment getTextAlignment() {
420 return textAlignment == null ? TextAlignment.LEFT : textAlignment.get();
421 }
422
423 public final ObjectProperty<TextAlignment> textAlignmentProperty() {
424 if (textAlignment == null) {
425 textAlignment =
426 new StyleableObjectProperty<TextAlignment>(TextAlignment.LEFT) {
427 @Override public Object getBean() { return TextFlow.this; }
428 @Override public String getName() { return "textAlignment"; }
429 @Override public CssMetaData<TextFlow, TextAlignment> getCssMetaData() {
430 return StyleableProperties.TEXT_ALIGNMENT;
431 }
432 @Override public void invalidated() {
433 TextAlignment align = get();
434 if (align == null) align = TextAlignment.LEFT;
435 TextLayout layout = getTextLayout();
436 layout.setAlignment(align.ordinal());
437 requestLayout();
438 }
439 };
440 }
441 return textAlignment;
442 }
443
444 /**
445 * Defines the vertical space in pixel between lines.
446 *
447 * @defaultValue 0
448 *
449 * @since JavaFX 8.0
450 */
451 private DoubleProperty lineSpacing;
452
453 public final void setLineSpacing(double spacing) {
454 lineSpacingProperty().set(spacing);
455 }
456
457 public final double getLineSpacing() {
458 return lineSpacing == null ? 0 : lineSpacing.get();
459 }
460
461 public final DoubleProperty lineSpacingProperty() {
462 if (lineSpacing == null) {
463 lineSpacing =
464 new StyleableDoubleProperty(0) {
465 @Override public Object getBean() { return TextFlow.this; }
466 @Override public String getName() { return "lineSpacing"; }
467 @Override public CssMetaData<TextFlow, Number> getCssMetaData() {
468 return StyleableProperties.LINE_SPACING;
469 }
470 @Override public void invalidated() {
471 TextLayout layout = getTextLayout();
472 if (layout.setLineSpacing((float)get())) {
473 requestLayout();
474 }
475 }
476 };
477 }
478 return lineSpacing;
479 }
480
481 @Override public final double getBaselineOffset() {
482 Insets insets = getInsets();
483 double top = snapSpace(insets.getTop());
484 return top - getTextLayout().getBounds().getMinY();
485 }
486
487 /***************************************************************************
488 * *
489 * Stylesheet Handling *
490 * *
491 **************************************************************************/
492
493 /**
494 * Super-lazy instantiation pattern from Bill Pugh.
495 * @treatAsPrivate implementation detail
496 */
497 private static class StyleableProperties {
498
499 private static final
500 CssMetaData<TextFlow, TextAlignment> TEXT_ALIGNMENT =
501 new CssMetaData<TextFlow,TextAlignment>("-fx-text-alignment",
502 new EnumConverter<TextAlignment>(TextAlignment.class),
503 TextAlignment.LEFT) {
504
505 @Override public boolean isSettable(TextFlow node) {
506 return node.textAlignment == null || !node.textAlignment.isBound();
507 }
508
509 @Override public StyleableProperty<TextAlignment> getStyleableProperty(TextFlow node) {
510 return (StyleableProperty<TextAlignment>)node.textAlignmentProperty();
511 }
512 };
513
514 private static final
515 CssMetaData<TextFlow,Number> LINE_SPACING =
516 new CssMetaData<TextFlow,Number>("-fx-line-spacing",
517 SizeConverter.getInstance(), 0) {
518
519 @Override public boolean isSettable(TextFlow node) {
520 return node.lineSpacing == null || !node.lineSpacing.isBound();
521 }
522
523 @Override public StyleableProperty<Number> getStyleableProperty(TextFlow node) {
524 return (StyleableProperty<Number>)node.lineSpacingProperty();
525 }
526 };
527
528 private static final List<CssMetaData<? extends Styleable, ?>> STYLEABLES;
529 static {
530 final List<CssMetaData<? extends Styleable, ?>> styleables =
531 new ArrayList<CssMetaData<? extends Styleable, ?>>(Pane.getClassCssMetaData());
532 styleables.add(TEXT_ALIGNMENT);
533 styleables.add(LINE_SPACING);
534 STYLEABLES = Collections.unmodifiableList(styleables);
535 }
536 }
537
538 /**
539 * @return The CssMetaData associated with this class, which may include the
540 * CssMetaData of its super classes.
541 */
542 public static List<CssMetaData<? extends Styleable, ?>> getClassCssMetaData() {
543 return StyleableProperties.STYLEABLES;
544 }
545
546 @Override
547 public List<CssMetaData<? extends Styleable, ?>> getCssMetaData() {
548 return getClassCssMetaData();
549 }
550
551 /* The methods in this section are copied from Region due to package visibility restriction */
552 private static double snapSpace(double value, boolean snapToPixel) {
553 return snapToPixel ? Math.round(value) : value;
554 }
555
556 static double boundedSize(double min, double pref, double max) {
557 double a = pref >= min ? pref : min;
558 double b = min >= max ? min : max;
559 return a <= b ? a : b;
560 }
561
562 double computeChildPrefAreaWidth(Node child, Insets margin) {
563 return computeChildPrefAreaWidth(child, margin, -1);
564 }
565
566 double computeChildPrefAreaWidth(Node child, Insets margin, double height) {
567 final boolean snap = isSnapToPixel();
568 double top = margin != null? snapSpace(margin.getTop(), snap) : 0;
569 double bottom = margin != null? snapSpace(margin.getBottom(), snap) : 0;
570 double left = margin != null? snapSpace(margin.getLeft(), snap) : 0;
571 double right = margin != null? snapSpace(margin.getRight(), snap) : 0;
572 double alt = -1;
573 if (child.getContentBias() == Orientation.VERTICAL) { // width depends on height
574 alt = snapSize(boundedSize(
575 child.minHeight(-1), height != -1? height - top - bottom :
576 child.prefHeight(-1), child.maxHeight(-1)));
577 }
578 return left + snapSize(boundedSize(child.minWidth(alt), child.prefWidth(alt), child.maxWidth(alt))) + right;
579 }
580
581 double computeChildPrefAreaHeight(Node child, Insets margin) {
582 return computeChildPrefAreaHeight(child, margin, -1);
583 }
584
585 double computeChildPrefAreaHeight(Node child, Insets margin, double width) {
586 final boolean snap = isSnapToPixel();
587 double top = margin != null? snapSpace(margin.getTop(), snap) : 0;
588 double bottom = margin != null? snapSpace(margin.getBottom(), snap) : 0;
589 double left = margin != null? snapSpace(margin.getLeft(), snap) : 0;
590 double right = margin != null? snapSpace(margin.getRight(), snap) : 0;
591 double alt = -1;
592 if (child.getContentBias() == Orientation.HORIZONTAL) { // height depends on width
593 alt = snapSize(boundedSize(
594 child.minWidth(-1), width != -1? width - left - right :
595 child.prefWidth(-1), child.maxWidth(-1)));
596 }
597 return top + snapSize(boundedSize(child.minHeight(alt), child.prefHeight(alt), child.maxHeight(alt))) + bottom;
598 }
599 /* end of copied code */
600
601 @Override
602 public Object queryAccessibleAttribute(AccessibleAttribute attribute, Object... parameters) {
603 switch (attribute) {
604 case TEXT: {
605 String accText = getAccessibleText();
606 if (accText != null && !accText.isEmpty()) return accText;
607
608 StringBuilder title = new StringBuilder();
609 for (Node node: getChildren()) {
610 Object text = node.queryAccessibleAttribute(AccessibleAttribute.TEXT, parameters);
611 if (text != null) {
612 title.append(text.toString());
613 }
614 }
615 return title.toString();
616 }
617 default: return super.queryAccessibleAttribute(attribute, parameters);
618 }
619 }
620 }