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
155 /**
156 * Creates an empty TextFlow layout.
157 */
158 public TextFlow() {
159 super();
160 effectiveNodeOrientationProperty().addListener(observable -> checkOrientation());
161 setAccessibleRole(AccessibleRole.TEXT);
162 }
163
164 /**
165 * Creates a TextFlow layout with the given children.
166 *
167 * @param children children.
168 */
169 public TextFlow(Node... children) {
170 this();
171 getChildren().addAll(children);
172 }
173
174 private void checkOrientation() {
175 NodeOrientation orientation = getEffectiveNodeOrientation();
176 boolean rtl = orientation == NodeOrientation.RIGHT_TO_LEFT;
177 int dir = rtl ? TextLayout.DIRECTION_RTL : TextLayout.DIRECTION_LTR;
178 TextLayout layout = getTextLayout();
179 if (layout.setDirection(dir)) {
180 requestLayout();
181 }
182 }
183
184 /**
185 * Maps local point to index in the content.
186 *
187 * @param point the specified point to be tested
188 * @return a {@code HitInfo} representing the character index found
189 * @since 9
190 */
191 public final HitInfo hitTest(javafx.geometry.Point2D point) {
192 if (point != null) {
193 TextLayout layout = getTextLayout();
194 double x = point.getX()/* - getX()*/;
195 double y = point.getY()/* - getY()/* + getYRendering()*/;
196 TextLayout.Hit layoutHit = layout.getHitInfo((float)x, (float)y);
197 return new HitInfo(layoutHit.getCharIndex(), layoutHit.getInsertionIndex(),
198 layoutHit.isLeading(), null/*getText()*/);
199 } else {
200 return null;
201 }
202 }
203
204 /**
205 * Returns shape of caret in local coordinates.
206 *
207 * @param charIndex the character index for the caret
208 * @param caretBias whether the caret is biased on the leading edge of the character
209 * @return an array of {@code PathElement} which can be used to create a {@code Shape}
210 * @since 9
211 */
212 public PathElement[] caretShape(int charIndex, boolean leading) {
213 return getTextLayout().getCaretShape(charIndex, leading, 0, 0);
214 }
215
216 /**
217 * Returns shape for the range of the text in local coordinates.
218 *
219 * @param start the beginning character index for the range
220 * @param start the end character index (non-inclusive) for the range
221 * @return an array of {@code PathElement} which can be used to create a {@code Shape}
222 * @since 9
223 */
224 public final PathElement[] rangeShape(int start, int end) {
225 return getRange(start, end, TextLayout.TYPE_TEXT);
226 }
227
228 @Override
229 public boolean usesMirroring() {
230 return false;
231 }
232
233 @Override protected void setWidth(double value) {
234 if (value != getWidth()) {
235 TextLayout layout = getTextLayout();
236 Insets insets = getInsets();
237 double left = snapSpaceX(insets.getLeft());
238 double right = snapSpaceX(insets.getRight());
239 double width = Math.max(1, value - left - right);
240 layout.setWrapWidth((float)width);
241 super.setWidth(value);
242 }
243 }
244
245 @Override protected double computePrefWidth(double height) {
246 TextLayout layout = getTextLayout();
247 layout.setWrapWidth(0);
248 double width = layout.getBounds().getWidth();
249 Insets insets = getInsets();
250 double left = snapSpaceX(insets.getLeft());
251 double right = snapSpaceX(insets.getRight());
252 double wrappingWidth = Math.max(1, getWidth() - left - right);
253 layout.setWrapWidth((float)wrappingWidth);
254 return left + width + right;
255 }
256
257 @Override protected double computePrefHeight(double width) {
258 TextLayout layout = getTextLayout();
259 Insets insets = getInsets();
260 double left = snapSpaceX(insets.getLeft());
261 double right = snapSpaceX(insets.getRight());
262 if (width == USE_COMPUTED_SIZE) {
263 layout.setWrapWidth(0);
264 } else {
265 double wrappingWidth = Math.max(1, width - left - right);
266 layout.setWrapWidth((float)wrappingWidth);
267 }
268 double height = layout.getBounds().getHeight();
269 double wrappingWidth = Math.max(1, getWidth() - left - right);
270 layout.setWrapWidth((float)wrappingWidth);
271 double top = snapSpaceY(insets.getTop());
272 double bottom = snapSpaceY(insets.getBottom());
273 return top + height + bottom;
274 }
275
276 @Override protected double computeMinHeight(double width) {
277 return computePrefHeight(width);
278 }
279
280 @Override public void requestLayout() {
281 /* The geometry of text nodes can be changed during layout children.
282 * For that reason it has to call NodeHelper.geomChanged(this) causing
283 * requestLayout() to happen during layoutChildren().
284 * The inLayout flag prevents this call to cause any extra work.
285 */
286 if (inLayout) return;
287
288 /*
289 * There is no need to reset the text layout's content every time
290 * requestLayout() is called. For example, the content needs
291 * to be set when:
292 * children add or removed
293 * children managed state changes
294 * children geomChanged (width/height of embedded node)
295 * children content changes (text/font of text node)
296 * The content does not need to set when:
297 * the width/height changes in the region
298 * the insets changes in the region
299 *
300 * Unfortunately, it is not possible to know what change invoked request
301 * layout. The solution is to always reset the content in the text
302 * layout and rely on it to preserve itself if the new content equals to
303 * the old one. The cost to generate the new content is not avoid.
304 */
305 needsContent = true;
306 super.requestLayout();
307 }
308
309 @Override public Orientation getContentBias() {
310 return Orientation.HORIZONTAL;
311 }
312
313 @Override protected void layoutChildren() {
314 inLayout = true;
315 Insets insets = getInsets();
316 double top = snapSpaceY(insets.getTop());
317 double left = snapSpaceX(insets.getLeft());
318
319 GlyphList[] runs = getTextLayout().getRuns();
320 for (int j = 0; j < runs.length; j++) {
321 GlyphList run = runs[j];
322 TextSpan span = run.getTextSpan();
323 if (span instanceof EmbeddedSpan) {
324 Node child = ((EmbeddedSpan)span).getNode();
325 Point2D location = run.getLocation();
326 double baselineOffset = -run.getLineBounds().getMinY();
327
328 layoutInArea(child, left + location.x, top + location.y,
329 run.getWidth(), run.getHeight(),
330 baselineOffset, null, true, true,
331 HPos.CENTER, VPos.BASELINE);
332 }
333 }
334
335 List<Node> managed = getManagedChildren();
336 for (Node node: managed) {
337 if (node instanceof Text) {
338 Text text = (Text)node;
339 text.layoutSpan(runs);
340 BaseBounds spanBounds = text.getSpanBounds();
341 text.relocate(left + spanBounds.getMinX(),
342 top + spanBounds.getMinY());
343 }
344 }
345 inLayout = false;
346 }
347
348 private PathElement[] getRange(int start, int end, int type) {
349 TextLayout layout = getTextLayout();
350 return layout.getRange(start, end, type, 0, 0);
351 }
352
353 private static class EmbeddedSpan implements TextSpan {
354 RectBounds bounds;
355 Node node;
356 public EmbeddedSpan(Node node, double baseline, double width, double height) {
357 this.node = node;
358 bounds = new RectBounds(0, (float)-baseline,
359 (float)width, (float)(height - baseline));
360 }
361
362 @Override public String getText() {
363 return "\uFFFC";
364 }
365
366 @Override public Object getFont() {
367 return null;
368 }
369
370 @Override public RectBounds getBounds() {
371 return bounds;
372 }
373
374 public Node getNode() {
375 return node;
376 }
377 }
378
379 TextLayout getTextLayout() {
380 if (layout == null) {
381 TextLayoutFactory factory = Toolkit.getToolkit().getTextLayoutFactory();
382 layout = factory.createLayout();
383 needsContent = true;
384 }
385 if (needsContent) {
386 List<Node> children = getManagedChildren();
387 TextSpan[] spans = new TextSpan[children.size()];
388 for (int i = 0; i < spans.length; i++) {
389 Node node = children.get(i);
390 if (node instanceof Text) {
391 spans[i] = ((Text)node).getTextSpan();
392 } else {
393 /* Creating a text span every time forces text layout
394 * to run a full text analysis in the new content.
395 */
396 double baseline = node.getBaselineOffset();
397 if (baseline == BASELINE_OFFSET_SAME_AS_HEIGHT) {
398 baseline = node.getLayoutBounds().getHeight();
399 }
400 double width = computeChildPrefAreaWidth(node, null);
401 double height = computeChildPrefAreaHeight(node, null);
402 spans[i] = new EmbeddedSpan(node, baseline, width, height);
403 }
404 }
405 layout.setContent(spans);
406 needsContent = false;
407 }
408 return layout;
409 }
410
411 /**
412 * Defines horizontal text alignment.
413 *
414 * @defaultValue TextAlignment.LEFT
415 */
416 private ObjectProperty<TextAlignment> textAlignment;
417
418 public final void setTextAlignment(TextAlignment value) {
419 textAlignmentProperty().set(value);
420 }
421
422 public final TextAlignment getTextAlignment() {
423 return textAlignment == null ? TextAlignment.LEFT : textAlignment.get();
424 }
425
426 public final ObjectProperty<TextAlignment> textAlignmentProperty() {
427 if (textAlignment == null) {
428 textAlignment =
429 new StyleableObjectProperty<TextAlignment>(TextAlignment.LEFT) {
430 @Override public Object getBean() { return TextFlow.this; }
431 @Override public String getName() { return "textAlignment"; }
432 @Override public CssMetaData<TextFlow, TextAlignment> getCssMetaData() {
433 return StyleableProperties.TEXT_ALIGNMENT;
434 }
435 @Override public void invalidated() {
436 TextAlignment align = get();
437 if (align == null) align = TextAlignment.LEFT;
438 TextLayout layout = getTextLayout();
439 layout.setAlignment(align.ordinal());
440 requestLayout();
441 }
442 };
443 }
444 return textAlignment;
445 }
446
447 /**
448 * Defines the vertical space in pixel between lines.
449 *
450 * @defaultValue 0
451 *
452 * @since JavaFX 8.0
453 */
454 private DoubleProperty lineSpacing;
455
456 public final void setLineSpacing(double spacing) {
457 lineSpacingProperty().set(spacing);
458 }
459
460 public final double getLineSpacing() {
461 return lineSpacing == null ? 0 : lineSpacing.get();
462 }
463
464 public final DoubleProperty lineSpacingProperty() {
465 if (lineSpacing == null) {
466 lineSpacing =
467 new StyleableDoubleProperty(0) {
468 @Override public Object getBean() { return TextFlow.this; }
469 @Override public String getName() { return "lineSpacing"; }
470 @Override public CssMetaData<TextFlow, Number> getCssMetaData() {
471 return StyleableProperties.LINE_SPACING;
472 }
473 @Override public void invalidated() {
474 TextLayout layout = getTextLayout();
475 if (layout.setLineSpacing((float)get())) {
476 requestLayout();
477 }
478 }
479 };
480 }
481 return lineSpacing;
482 }
483
484 @Override public final double getBaselineOffset() {
485 Insets insets = getInsets();
486 double top = snapSpaceY(insets.getTop());
487 return top - getTextLayout().getBounds().getMinY();
488 }
489
490 /***************************************************************************
491 * *
492 * Stylesheet Handling *
493 * *
494 **************************************************************************/
495
496 /*
497 * Super-lazy instantiation pattern from Bill Pugh.
498 */
499 private static class StyleableProperties {
500
501 private static final
502 CssMetaData<TextFlow, TextAlignment> TEXT_ALIGNMENT =
503 new CssMetaData<TextFlow,TextAlignment>("-fx-text-alignment",
504 new EnumConverter<TextAlignment>(TextAlignment.class),
505 TextAlignment.LEFT) {
506
507 @Override public boolean isSettable(TextFlow node) {
508 return node.textAlignment == null || !node.textAlignment.isBound();
509 }
510
511 @Override public StyleableProperty<TextAlignment> getStyleableProperty(TextFlow node) {
512 return (StyleableProperty<TextAlignment>)node.textAlignmentProperty();
513 }
514 };
515
516 private static final
517 CssMetaData<TextFlow,Number> LINE_SPACING =
518 new CssMetaData<TextFlow,Number>("-fx-line-spacing",
519 SizeConverter.getInstance(), 0) {
520
521 @Override public boolean isSettable(TextFlow node) {
522 return node.lineSpacing == null || !node.lineSpacing.isBound();
523 }
524
525 @Override public StyleableProperty<Number> getStyleableProperty(TextFlow node) {
526 return (StyleableProperty<Number>)node.lineSpacingProperty();
527 }
528 };
529
530 private static final List<CssMetaData<? extends Styleable, ?>> STYLEABLES;
531 static {
532 final List<CssMetaData<? extends Styleable, ?>> styleables =
533 new ArrayList<CssMetaData<? extends Styleable, ?>>(Pane.getClassCssMetaData());
534 styleables.add(TEXT_ALIGNMENT);
535 styleables.add(LINE_SPACING);
536 STYLEABLES = Collections.unmodifiableList(styleables);
537 }
538 }
539
540 /**
541 * @return The CssMetaData associated with this class, which may include the
542 * CssMetaData of its super classes.
543 */
544 public static List<CssMetaData<? extends Styleable, ?>> getClassCssMetaData() {
545 return StyleableProperties.STYLEABLES;
546 }
547
548 @Override
549 public List<CssMetaData<? extends Styleable, ?>> getCssMetaData() {
550 return getClassCssMetaData();
551 }
552
553 /* The methods in this section are copied from Region due to package visibility restriction */
554 private static double snapSpace(double value, boolean snapToPixel) {
555 return snapToPixel ? Math.round(value) : value;
556 }
557
558 static double boundedSize(double min, double pref, double max) {
559 double a = pref >= min ? pref : min;
560 double b = min >= max ? min : max;
561 return a <= b ? a : b;
562 }
563
564 double computeChildPrefAreaWidth(Node child, Insets margin) {
565 return computeChildPrefAreaWidth(child, margin, -1);
566 }
567
568 double computeChildPrefAreaWidth(Node child, Insets margin, double height) {
569 final boolean snap = isSnapToPixel();
570 double top = margin != null? snapSpace(margin.getTop(), snap) : 0;
571 double bottom = margin != null? snapSpace(margin.getBottom(), snap) : 0;
572 double left = margin != null? snapSpace(margin.getLeft(), snap) : 0;
573 double right = margin != null? snapSpace(margin.getRight(), snap) : 0;
574 double alt = -1;
575 if (child.getContentBias() == Orientation.VERTICAL) { // width depends on height
576 alt = snapSizeY(boundedSize(
577 child.minHeight(-1), height != -1? height - top - bottom :
578 child.prefHeight(-1), child.maxHeight(-1)));
579 }
580 return left + snapSizeX(boundedSize(child.minWidth(alt), child.prefWidth(alt), child.maxWidth(alt))) + right;
581 }
582
583 double computeChildPrefAreaHeight(Node child, Insets margin) {
584 return computeChildPrefAreaHeight(child, margin, -1);
585 }
586
587 double computeChildPrefAreaHeight(Node child, Insets margin, double width) {
588 final boolean snap = isSnapToPixel();
589 double top = margin != null? snapSpace(margin.getTop(), snap) : 0;
590 double bottom = margin != null? snapSpace(margin.getBottom(), snap) : 0;
591 double left = margin != null? snapSpace(margin.getLeft(), snap) : 0;
592 double right = margin != null? snapSpace(margin.getRight(), snap) : 0;
593 double alt = -1;
594 if (child.getContentBias() == Orientation.HORIZONTAL) { // height depends on width
595 alt = snapSizeX(boundedSize(
596 child.minWidth(-1), width != -1? width - left - right :
597 child.prefWidth(-1), child.maxWidth(-1)));
598 }
599 return top + snapSizeY(boundedSize(child.minHeight(alt), child.prefHeight(alt), child.maxHeight(alt))) + bottom;
600 }
601 /* end of copied code */
602
603 @Override
604 public Object queryAccessibleAttribute(AccessibleAttribute attribute, Object... parameters) {
605 switch (attribute) {
606 case TEXT: {
607 String accText = getAccessibleText();
608 if (accText != null && !accText.isEmpty()) return accText;
609
610 StringBuilder title = new StringBuilder();
611 for (Node node: getChildren()) {
612 Object text = node.queryAccessibleAttribute(AccessibleAttribute.TEXT, parameters);
613 if (text != null) {
614 title.append(text.toString());
615 }
616 }
617 return title.toString();
618 }
619 default: return super.queryAccessibleAttribute(attribute, parameters);
620 }
621 }
622 }