1 #ifndef __DALI_TOOLKIT_TEXT_VIEW_H__
2 #define __DALI_TOOLKIT_TEXT_VIEW_H__
5 // Copyright (c) 2014 Samsung Electronics Co., Ltd.
7 // Licensed under the Flora License, Version 1.0 (the License);
8 // you may not use this file except in compliance with the License.
9 // You may obtain a copy of the License at
11 // http://floralicense.org/license/
13 // Unless required by applicable law or agreed to in writing, software
14 // distributed under the License is distributed on an AS IS BASIS,
15 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 // See the License for the specific language governing permissions and
17 // limitations under the License.
21 * @addtogroup CAPI_DALI_TOOLKIT_TEXT_VIEW_MODULE
29 #include <dali-toolkit/public-api/controls/alignment/alignment.h>
30 #include <dali-toolkit/public-api/markup-processor/markup-processor.h>
32 namespace Dali DALI_IMPORT_API
38 namespace Internal DALI_INTERNAL
44 * @brief TextView is a layout container for text with alignment, multi-line wrapping and formatting support.
46 * Different multi-line and exceed policies could be chosen to represent the given text.
47 * \see Toolkit::TextView::SetMultilinePolicy \see Toolkit::TextView::SetExceedPolicy
49 * Multi-line policies:
51 * <li>\e Split by new line character.
52 * Text will split when a '\\n' character is found.
54 * <li>\e Split by word.
55 * Text will split when a '\\n' character is found or if the text doesn't fit in the text view width.
56 * In that case, some words will be moved to a new line.
58 * <li>\e Split by character.
59 * Text will split when a '\\n' character is found or if the text doesn't fit in the text view width.
60 * In that case, words which doesn't fit will be split in two and the remaining text moved to a new line.
63 * Exceed policies work in combination with multi-line policies:
65 * <li>\e Original size.
66 * Text will be displayed with its original size.
69 * Text will be truncated.
72 * Text will be faded out.
75 * Text will be split and moved to a new line.
77 * <li>\e Shrink to fit.
78 * Text will be shrink to fit in the text view's boundary.
80 * <li>\e EllipsizeEnd.
81 * Text will be ellipsized at the end.
85 * Text alignment could be set to align the whole text block inside the text view's boundary. \see Toolkit::TextView::SetTextAlignment.
87 * Line justification could be set to align lines inside a text block. \see Toolkit::TextView::SetLineJustification.
89 * A default font could be set through the \see Toolkit::TextView::SetFont method. If any font is set, text view automatically detects a suitable font for every character.
92 * 1) Use the font specified in text decoration.
93 * 2) Use automatic font detection.
95 * Integration with other classes (GetSizeAndPositionTable )
97 * Text decoration ( Color, Font, Size, italic and all features supported in TextActor )
99 class TextView : public Control
104 static const char* const SIGNAL_TEXT_SCROLLED; ///< Signal emitted when the scroll position changes. @see SignalScrolled()
107 * @brief Structure used to retrieve Layout info per character.
109 struct CharacterLayoutInfo
112 * @brief Default constructor.
114 * Initializes all members to their default values.
116 CharacterLayoutInfo();
119 * @brief Empty destructor.
121 * @note Added to increase coverage.
123 ~CharacterLayoutInfo();
126 * @brief Copy constructor.
128 CharacterLayoutInfo( const CharacterLayoutInfo& characterLayoutInfo );
131 * @brief Assignment operator.
133 CharacterLayoutInfo& operator=( const CharacterLayoutInfo& character );
136 * @brief Constructor.
138 * @param[in] size of the character.
139 * @param[in] position of the character.
140 * @param[in] isNewLineChar Whether the character is a new line character.
141 * @param[in] isRightToLeftCharacter Whether is a right to left character.
142 * @param[in] visible Whether is visible.
143 * @param[in] descender of the character (distance from the base line to the bottom of the character.)
145 CharacterLayoutInfo( const Size& size,
146 const Vector3& position,
148 bool isRightToLeftCharacter,
152 Size mSize; ///< Size of the group of characters.
153 Vector3 mPosition; ///< Position of the group of characters within the text view.
154 bool mIsNewLineChar:1; ///< Whether this group of characters represent a new line.
155 bool mIsRightToLeftCharacter:1; ///< Whether it's a right-to-left character.
156 bool mIsVisible:1; ///< Whether this group of characters is visible or not.
157 float mDescender; ///< The character's descender which is the distance from the baseline to the bottom of the character
160 typedef std::vector<CharacterLayoutInfo> CharacterLayoutInfoContainer; ///< Container of Character layouts
163 * @brief Stores some info about a laid-out line.
165 struct LineLayoutInfo
167 std::size_t mCharacterGlobalIndex; ///< Global index within the whole text of the first character of current laid-out line.
168 Size mSize; ///< Size of the current laid-out line.
169 float mAscender; ///< The max ascender of the current laid-out line.
172 typedef std::vector<LineLayoutInfo> LineLayoutInfoContainer; ///< Container of line layouts
175 * @brief How text is laid out.
177 struct TextLayoutInfo
180 * @brief Default constructor.
185 * @brief Empty destructor.
187 * @note Added to increase coverage.
192 * @brief Copy constructor.
194 TextLayoutInfo( const TextLayoutInfo& textLayoutInfo );
197 * @brief Assignment operator.
199 TextLayoutInfo& operator=( const TextLayoutInfo& textLayoutInfo );
201 CharacterLayoutInfoContainer mCharacterLayoutInfoTable; ///< The table of character positions and sizes sorted by the characters' visual index.
202 LineLayoutInfoContainer mLines; ///< For each laid-out line, it stores an index to the first character of the line.
203 std::vector<int> mCharacterLogicalToVisualMap; ///< The map to store the character's logical (input) index according to its visual (reordered) index.
204 std::vector<int> mCharacterVisualToLogicalMap; ///< The map to store the character's visual (reordered) index according to its logical (input) index.
205 Size mTextSize; ///< Text size after relayout.
206 Vector2 mScrollOffset; ///< Scroll's position.
210 * @brief This structure represents a fade boundary.
212 * If Exceed policy is set to Fade all text which does not fit within the text-view fade boundary is faded out. Text which exceeds the text-view boundary becomes invisible.
213 * The \e left, \e right, \e top and \e bottom values are positive, in pixels and set the distances between the text-view and fade boundaries.
218 * @brief Default constructor.
220 * Initializes all values to 0. It means no fade boundary.
225 * @brief Constructor.
227 * Initializes the fade boundary with the given values.
229 * @param[in] left value in pixels.
230 * @param[in] right value in pixels.
231 * @param[in] top value in pixels.
232 * @param[in] bottom value in pixels.
234 FadeBoundary( PixelSize left, PixelSize right, PixelSize top, PixelSize bottom );
236 PixelSize mLeft; ///< The left fade boundary
237 PixelSize mRight; ///< The right fade boundary
238 PixelSize mTop; ///< The top fade boundary
239 PixelSize mBottom; ///< The bottom fade bounday
243 * @brief Define how to split the text in lines.
245 * SplitByNewLineChar will split the text in lines when a '\\n' character is found.
246 * SplitByWord has effect only when TextView size is assigned.
247 * It will split the text in lines when a '\\n' character is found or if a line exceeds the TextView's boundary. This option won't split a word in two.
248 * SplitByChar has effect only when TextView size is assigned.
249 * It will split the text in lines when a '\\n' character is found or if a line exceeds the TextView's boundary. This option might split a word in two.
250 * The default value is SplitByNewLineChar.
254 SplitByNewLineChar, ///< Text lines will split when '\\n' character is found.
255 SplitByWord, ///< Text lines will split by word or if '\\n' character is found. It has effect only when TextView size is assigned.
256 SplitByChar ///< Text lines will split by char or if '\\n' character is found. It has effect only when TextView size is assigned.
260 * @brief Define how to display the text when it doesn't fit inside the TextView.
262 * The default value is ShrinkToFit.
266 Original, ///< Will display the text in its original size. If a line, a word or a character is bigger than the TextView size it may exceed its boundary.
267 Truncate, ///< Will display the text in its original size. It won't display the text which exceeds the TextView boundary.
268 Fade, ///< Will display the text in its original size. It won't display the text which exceeds the TextView boundary. It fades the text out.
269 Split, ///< Will split the text in a new line.
270 ShrinkToFit, ///< Will shrink the text to fit the TextView boundary.
271 EllipsizeEnd ///< Will ellipsize the text by the end.
275 * @brief Define how to justify lines inside the text area.
277 * The default value is Left.
279 enum LineJustification
281 Left, ///< Justify to the left.
282 Center, ///< Centered.
283 Right, ///< Justify to the right.
284 Justified ///< Line justified.
289 * @brief Create an TextView handle; this can be initialised with TextView::New().
291 * Calling member functions with an uninitialised Dali::Object handle is not allowed.
296 * @brief Copy constructor.
298 * Creates another handle that points to the same real object
299 * @param[in] handle The handle to copy from
301 TextView( const TextView& handle );
304 * @brief Assignment operator.
306 * Changes this handle to point to another real object
307 * @param[in] handle The handle to copy from
308 * @return a reference to this
310 TextView& operator=( const TextView& handle );
313 * @brief Create a TextView control with no text.
315 * @return A handle the TextView control.
317 static TextView New();
320 * @brief Create a TextView control.
322 * @param[in] text to display.
323 * @return A handle the TextView control.
325 static TextView New( const std::string& text );
328 * @copydoc TextView New( const std::string& text )
330 static TextView New( const MarkupProcessor::StyledTextArray& text );
333 * @brief Downcast an Object handle to TextView.
335 * If handle points to a TextView the
336 * downcast produces valid handle. If not the returned handle is left uninitialized.
337 * @param[in] handle Handle to an object
338 * @return handle to a TextView or an uninitialized handle
340 static TextView DownCast( BaseHandle handle );
343 * @brief Virtual destructor.
345 * Dali::Object derived classes typically do not contain member data.
350 * @brief Replace the current text with a new text string.
352 * @param[in] text to display. The string may contain style tags.
354 void SetText( const std::string& text );
357 * @brief Replace the current text with a new text string with style.
359 * @param[in] text with style to display.
361 void SetText( const MarkupProcessor::StyledTextArray& text );
364 * @brief Inserts the given text in the specified position.
366 * @param[in] position Where the given text is going to be added.
367 * @param[in] text The text to be added.
369 void InsertTextAt( std::size_t position, const std::string& text );
372 * @copydoc InsertTextAt( std::size_t position, const std::string& text )
374 void InsertTextAt( std::size_t position, const MarkupProcessor::StyledTextArray& text );
377 * @brief Replaces part of the text.
379 * It removes the specified number of characters from the given position and inserts the given text in the same specified position.
381 * @param[in] position of the first character to be removed and Where the given text is going to be added.
382 * @param[in] numberOfCharacters number of characters to be removed.
383 * @param[in] text The text to be added.
385 void ReplaceTextFromTo( std::size_t position, std::size_t numberOfCharacters, const std::string& text );
388 * @copydoc ReplaceTextFromTo( std::size_t position, std::size_t numberOfCharacters, const std::string& text )
390 void ReplaceTextFromTo( std::size_t position, std::size_t numberOfCharacters, const MarkupProcessor::StyledTextArray& text );
393 * @brief Removes the specified number of characters from the given position.
395 * @param[in] position of the first character to be removed.
396 * @param[in] numberOfCharacters number of characters to be removed.
398 void RemoveTextFrom( std::size_t position, std::size_t numberOfCharacters );
401 * @brief Get the currently displayed text.
403 * @return The currently displayed text.
405 std::string GetText() const;
408 * @brief Sets a line height offset.
410 * The line height offset will be added to the font line height.
411 * @param [in] offset The height offset in PointSize units.
413 void SetLineHeightOffset( PointSize offset );
416 * @brief Retrieves the line height offset.
418 * @return The line height offset in PointSize units.
420 PointSize GetLineHeightOffset() const;
423 * @brief Sets the given style to the current text.
425 * By default all style settings are applied but a bit mask could be used to modify only certain style settings.
426 * @note TextView doesn't store a copy of the given style, it applies the given style to the current text only.
427 * Subsequent calls to SetText() will override any style set by this method.
428 * @param[in] style The given style
429 * @param[in] mask The bit mask.
431 void SetStyleToCurrentText( const TextStyle& style, TextStyle::Mask mask = TextStyle::ALL );
434 * @brief Set the current text alignment.
436 * Default alignment is (HorizontalCenter | VerticalCenter)
437 * @param[in] align The new alignment option.
439 void SetTextAlignment( Alignment::Type align );
442 * @brief Get the current text alignment combined into a single value.
444 * The values can be tested by using the & operator
445 * and the desired flag. e.g. if (GetTextAlignment() & HorizontalCentre) ...
446 * @return the combined alignment
448 Alignment::Type GetTextAlignment() const;
451 * @brief Sets how to split the text in lines policy.
453 * @param policy The multi-line policy. SplitByNewLineChar is set by default.
455 void SetMultilinePolicy( MultilinePolicy policy );
458 * @brief Gets the split in lines policy.
460 * @return The multi-line policy.
462 MultilinePolicy GetMultilinePolicy() const;
465 * @brief Sets how to display the text inside the TextView when it exceeds the text-view's width.
467 * @param policy The exceed policy. Original is set by default.
469 void SetWidthExceedPolicy( ExceedPolicy policy );
472 * @brief Gets the width exceed policy.
474 * @return The exceed policy.
476 ExceedPolicy GetWidthExceedPolicy() const;
479 * @brief Sets how to display the text inside the TextView when it exceeds the text-view's height.
481 * @param policy The exceed policy. Original is set by default.
483 void SetHeightExceedPolicy( ExceedPolicy policy );
486 * @brief Gets the height exceed policy.
488 * @return The exceed policy.
490 ExceedPolicy GetHeightExceedPolicy() const;
493 * @brief Sets how to justify lines inside the text area.
495 * @param justification The line justification. Left is set by default.
497 void SetLineJustification( LineJustification justification );
500 * @brief Gets the line justification.
502 * @return The line justification.
504 LineJustification GetLineJustification() const;
507 * @brief Sets a fade boundary.
511 * @param[in] fadeBoundary The given fade boundary.
513 void SetFadeBoundary( const FadeBoundary& fadeBoundary );
516 * @brief Retrieves the fade boundary.
520 * @return The fade boundary.
522 const FadeBoundary& GetFadeBoundary() const;
525 * @brief Sets the ellipsize text.
527 * @param[in] ellipsizeText The new text. The string may contain style tags. By default the ellipsize text is '...'
529 void SetEllipsizeText( const std::string& ellipsizeText );
532 * @brief Sets the ellipsize text.
534 * @param[in] ellipsizeText The new text with its style.
536 void SetEllipsizeText( const MarkupProcessor::StyledTextArray& ellipsizeText );
539 * @brief Retrieves the ellipsize text.
541 * @return The ellipsize text.
543 std::string GetEllipsizeText() const;
546 * @brief A mechanism to retrieve layout information from the TextView.
548 * It produces a vector of CharcterLayoutInfo structures which describe the size and position of each character,
549 * two vectors which maps the logical and visual positions of the characters in a bidirectional text, the size
550 * of the whole laid-out text and the scroll offset value.
552 * @see TextLayoutInfo.
554 * @param[out] textLayoutInfo A structure with text layout information.
556 void GetTextLayoutInfo( TextLayoutInfo& textLayoutInfo );
559 * @brief Allows modification of text-actor's position in the depth sort algorithm.
561 * @see Dali::RenderableActor::SetSortModifier()
562 * @param [in] depthOffset the offset to be given to the internal text-actors. Positive values pushing it further back.
564 void SetSortModifier( float depthOffset );
567 * @brief Sets whether text-view renders text using a previously generated snapshot.
569 * Rendering long text using a snapshot may increase performance. The default value is \e true (render using a snapshot).
571 * @param[in] enable Whether text-view is using a snapshot to render text.
573 void SetSnapshotModeEnabled( bool enable );
576 * @brief Retrieves whether text-view is using a snapshot to render text.
578 * @return \e true if text-view is using a snapshot to render text, otherwhise it returns \e false.
580 bool IsSnapshotModeEnabled() const;
583 * @brief Enables or disables the text scroll.
585 * When scroll is enabled, snapshot mode will be enabled automatically. Equally, if scroll is disabled
586 * the snapshot mode is restored to the previous value.
588 * @param[in] enable Whether to enable the text scroll.
590 void SetScrollEnabled( bool enable );
593 * @brief Retrieves whether the text scroll is enabled.
595 * @return \e true if the scroll is enabled.
597 bool IsScrollEnabled() const;
600 * @brief Sets a new scroll position.
602 * The new scroll position set could be trimmed if the text doesn't cover the whole text-view.
603 * i.e. If a text-view is 100x100 and a text is 200x100 a scroll position beyond 50x0 will be trimmed to 50x0.
605 * Call IsScrollPositionTrimmed() to know if the last scroll position set has been trimmed.
607 * A signal is emitted. @see ScrolledSignal().
609 * @param[in] position The new scroll position.
611 void SetScrollPosition( const Vector2& position );
614 * @brief Recrieves current scroll position.
616 * @return The scroll position.
618 const Vector2& GetScrollPosition() const;
621 * @brief Whether the last scroll position set was trimmed.
623 * @return \e true if the last scroll position set was trimmed, otherwise \e false.
625 bool IsScrollPositionTrimmed() const;
628 /// @brief Signal types
629 typedef SignalV2< void ( TextView textView, Vector2 scrollDelta ) > ScrolledSignalV2;
632 * @brief Signal emitted when the scroll position changes.
634 * A callback with the following prototype can be connected to this signal.
636 * Callback(TextView textView, Vector2 scrollDelta)
638 * \e textView is the handle of the text-view emitting the signal.
639 * \e scrollDelta is the differente of the current scroll position with the previous one.
640 * @return The signal to connect to
642 ScrolledSignalV2& ScrolledSignal();
644 public: // Not intended for application developers
647 * @brief Creates a handle using the Toolkit::Internal implementation.
649 * @param[in] implementation The Control implementation.
651 TextView( Internal::TextView& implementation );
654 * @brief Allows the creation of this Control from an Internal::CustomActor pointer.
656 * @param[in] internal A pointer to the internal CustomActor.
658 TextView( Dali::Internal::CustomActor* internal );
661 } // namespace Toolkit
668 #endif // __DALI_TOOLKIT_ITEM_VIEW_H__