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 Apache License, Version 2.0 (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://www.apache.org/licenses/LICENSE-2.0
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.
25 #include <dali-toolkit/public-api/controls/alignment/alignment.h>
26 #include <dali-toolkit/public-api/markup-processor/markup-processor.h>
28 namespace Dali DALI_IMPORT_API
34 namespace Internal DALI_INTERNAL
40 * @brief The TextView class is a UI Dali::Toolkit::Control designed to extend the capabilities of the basic Dali::TextActor.
42 * It provides support for multi-line wrapping, multi-language font detection, text alignment, scrolling and styling.
44 * See the \link text-view Text View \endlink page of the Programming Guide for more details and examples.
46 class TextView : public Control
51 static const char* const SIGNAL_TEXT_SCROLLED; ///< Signal emitted when the scroll position changes. @see ScrolledSignal()
54 static const Property::Index PROPERTY_MARKUP_ENABLED; ///< name "markup-enabled", @see SetMarkupProcessingEnabled(), type BOOLEAN
55 static const Property::Index PROPERTY_TEXT; ///< name "text", @see SetText(), type STRING
56 static const Property::Index PROPERTY_MULTILINE_POLICY; ///< name "multiline-policy", @see SetMultilinePolicy(), type STRING
57 static const Property::Index PROPERTY_WIDTH_EXCEED_POLICY; ///< name "width-exceed-policy", @see SetWidthExceedPolicy(), type STRING
58 static const Property::Index PROPERTY_HEIGHT_EXCEED_POLICY; ///< name "height-exceed-policy", @see SetHeightExceedPolicy(), type STRING
59 static const Property::Index PROPERTY_LINE_JUSTIFICATION; ///< name "line-justification", @see SetLineJustification(), type STRING
60 static const Property::Index PROPERTY_FADE_BOUNDARY; ///< name "fade-boundary", @see SetFadeBoundary(), type VECTOR4
61 static const Property::Index PROPERTY_LINE_HEIGHT_OFFSET; ///< name "line-height-offset", @see SetLineHeightOffset(), type FLOAT
62 static const Property::Index PROPERTY_HORIZONTAL_ALIGNMENT; ///< name "horizontal-alignment", @see SetTextAlignment(), type STRING
63 static const Property::Index PROPERTY_VERTICAL_ALIGNMENT; ///< name "vertical-alignment", @see SetTextAlignment(), type STRING
66 * @brief Structure used to retrieve Layout info per character.
68 struct CharacterLayoutInfo
71 * @brief Default constructor.
73 * Initializes all members to their default values.
75 CharacterLayoutInfo();
78 * @brief Empty destructor.
80 * @note Added to increase coverage.
82 ~CharacterLayoutInfo();
85 * @brief Copy constructor.
87 CharacterLayoutInfo( const CharacterLayoutInfo& characterLayoutInfo );
90 * @brief Assignment operator.
92 CharacterLayoutInfo& operator=( const CharacterLayoutInfo& character );
97 * @param[in] size of the character.
98 * @param[in] position of the character.
99 * @param[in] isNewLineChar Whether the character is a new line character.
100 * @param[in] isRightToLeftCharacter Whether is a right to left character.
101 * @param[in] visible Whether is visible.
102 * @param[in] descender of the character (distance from the base line to the bottom of the character.)
104 CharacterLayoutInfo( const Size& size,
105 const Vector3& position,
107 bool isRightToLeftCharacter,
111 Size mSize; ///< Size of the group of characters.
112 Vector3 mPosition; ///< Position of the character within the text view.
113 bool mIsNewLineChar:1; ///< Whether this character represent a new line.
114 bool mIsRightToLeftCharacter:1; ///< Whether it's a right-to-left character.
115 bool mIsVisible:1; ///< Whether this character is visible or not.
116 float mDescender; ///< The character's descender which is the distance from the baseline to the bottom of the character
119 typedef std::vector<CharacterLayoutInfo> CharacterLayoutInfoContainer; ///< Container of layout info per character.
122 * @brief Stores some info about a laid-out line.
124 struct LineLayoutInfo
126 std::size_t mCharacterGlobalIndex; ///< Global index within the whole text of the first character of current laid-out line.
127 Size mSize; ///< Size of the current laid-out line.
128 float mAscender; ///< The max ascender of the current laid-out line.
131 typedef std::vector<LineLayoutInfo> LineLayoutInfoContainer; ///< Container of layout info per line.
134 * @brief How text is laid out.
136 struct TextLayoutInfo
139 * @brief Default constructor.
144 * @brief Empty destructor.
146 * @note Added to increase coverage.
151 * @brief Copy constructor.
153 TextLayoutInfo( const TextLayoutInfo& textLayoutInfo );
156 * @brief Assignment operator.
158 TextLayoutInfo& operator=( const TextLayoutInfo& textLayoutInfo );
160 CharacterLayoutInfoContainer mCharacterLayoutInfoTable; ///< The table of character's positions and sizes sorted by the character's visual index.
161 LineLayoutInfoContainer mLines; ///< For each laid-out line, it stores an index to the first character of the line.
162 std::vector<int> mCharacterLogicalToVisualMap; ///< The map to store the character's logical (input) index according to its visual (reordered) index.
163 std::vector<int> mCharacterVisualToLogicalMap; ///< The map to store the character's visual (reordered) index according to its logical (input) index.
164 Size mTextSize; ///< Text size after relayout.
165 Vector2 mScrollOffset; ///< Scroll's position.
169 * @brief This structure represents a fade boundary.
171 * If the 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.
172 * 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.
177 * @brief Default constructor.
179 * Initializes all values to 0. It means no fade boundary.
184 * @brief Constructor.
186 * Initializes the fade boundary with the given values.
188 * @param[in] left value in pixels.
189 * @param[in] right value in pixels.
190 * @param[in] top value in pixels.
191 * @param[in] bottom value in pixels.
193 FadeBoundary( PixelSize left, PixelSize right, PixelSize top, PixelSize bottom );
195 PixelSize mLeft; ///< The left fade boundary
196 PixelSize mRight; ///< The right fade boundary
197 PixelSize mTop; ///< The top fade boundary
198 PixelSize mBottom; ///< The bottom fade bounday
202 * @brief Define how to wrap the text in lines.
204 * \e SplitByNewLineChar will wrap the text in lines when a '\\n' character or a \<br /\> is found.
205 * \e SplitByWord has effect only when TextView size is assigned.
206 * It will wrap the text in lines when a '\\n' character or a \<br /\> is found or if a line exceeds the TextView's boundary. This option won't split a word in two.
207 * \e SplitByChar has effect only when TextView size is assigned.
208 * It will wrap the text in lines when a '\\n' character or a \<br /\> is found or if a line exceeds the TextView's boundary. This option might split a word in two.
209 * The default value is \e SplitByNewLineChar.
213 SplitByNewLineChar, ///< Text lines will wrap when '\\n' character is found.
214 SplitByWord, ///< Text lines will wrap by word or if '\\n' character is found. It has effect only when TextView size is assigned.
215 SplitByChar ///< Text lines will wrap by char or if '\\n' character is found. It has effect only when TextView size is assigned.
219 * @brief Define how to display the text when it doesn't fit inside the TextView after the line wrap.
221 * The default value is \e Original.
225 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.
226 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.
227 Split, ///< Will split the text in a new line.
228 ShrinkToFit, ///< Will shrink the text to fit the TextView boundary.
229 EllipsizeEnd ///< Will ellipsize the text by the end.
233 * @brief Define how to justify lines inside the text area.
235 * The default value is \e Left.
237 enum LineJustification
239 Left, ///< Justify to the left.
240 Center, ///< Centered.
241 Right, ///< Justify to the right.
242 Justified ///< Line justified.
247 * @brief Create a TextView handle; this can be initialised with TextView::New().
249 * Calling member functions with an uninitialised Dali::Object handle is not allowed.
254 * @brief Copy constructor.
256 * Creates another handle that points to the same real object
257 * @param[in] handle The handle to copy from
259 TextView( const TextView& handle );
262 * @brief Assignment operator.
264 * Changes this handle to point to another real object
265 * @param[in] handle The handle to copy from
266 * @return a reference to this
268 TextView& operator=( const TextView& handle );
271 * @brief Create a TextView control with no text.
273 * @return A handle the TextView control.
275 static TextView New();
278 * @brief Create a TextView control.
280 * @param[in] text to display.
281 * @return A handle the TextView control.
283 static TextView New( const std::string& text );
286 * @brief Create a TextView control with styled text.
288 * @param[in] text The text with style to display.
289 * @return A handle the TextView control.
291 static TextView New( const MarkupProcessor::StyledTextArray& text );
294 * @brief Downcast an Object handle to TextView.
296 * If handle points to a TextView the
297 * downcast produces valid handle. If not the returned handle is left uninitialized.
298 * @param[in] handle Handle to an object
299 * @return handle to a TextView or an uninitialized handle
301 static TextView DownCast( BaseHandle handle );
306 * This is non-virtual since derived Handle types must not contain data or virtual methods.
311 * @brief Replace the current text with a new text string.
313 * @param[in] text to display. The string may contain style tags.
315 void SetText( const std::string& text );
318 * @brief Replace the current text with a new text string with style.
320 * @param[in] text The text with style to display.
322 void SetText( const MarkupProcessor::StyledTextArray& text );
325 * @brief Inserts the given text in the specified position.
327 * @param[in] position Where the given text is going to be added.
328 * @param[in] text The text to be added.
330 void InsertTextAt( std::size_t position, const std::string& text );
333 * @brief Inserts the given text with style in the specified position.
335 * @param[in] position Where the given text is going to be added.
336 * @param[in] text The text with style to be added.
338 void InsertTextAt( std::size_t position, const MarkupProcessor::StyledTextArray& text );
341 * @brief Replaces part of the text.
343 * It removes the specified number of characters from the given position and inserts the given text in the same specified position.
345 * @param[in] position of the first character to be removed and Where the given text is going to be added.
346 * @param[in] numberOfCharacters number of characters to be removed.
347 * @param[in] text The text to be added.
349 void ReplaceTextFromTo( std::size_t position, std::size_t numberOfCharacters, const std::string& text );
352 * @brief Replaces part of the text.
354 * It removes the specified number of characters from the given position and inserts the given text with style in the same specified position.
356 * @param[in] position of the first character to be removed and Where the given text is going to be added.
357 * @param[in] numberOfCharacters number of characters to be removed.
358 * @param[in] text The text with style to be added.
360 void ReplaceTextFromTo( std::size_t position, std::size_t numberOfCharacters, const MarkupProcessor::StyledTextArray& text );
363 * @brief Removes the specified number of characters from the given position.
365 * @param[in] position of the first character to be removed.
366 * @param[in] numberOfCharacters number of characters to be removed.
368 void RemoveTextFrom( std::size_t position, std::size_t numberOfCharacters );
371 * @brief Get the currently displayed text.
373 * @return The currently displayed text.
375 std::string GetText() const;
378 * @brief Sets a line height offset.
380 * The line height offset will be added to the font line height.
381 * @param [in] offset The height offset in PointSize units.
383 void SetLineHeightOffset( PointSize offset );
386 * @brief Retrieves the line height offset.
388 * @return The line height offset in PointSize units.
390 PointSize GetLineHeightOffset() const;
393 * @brief Sets the given style to the current text.
395 * By default all style settings are applied but a bit mask could be used to modify only certain style settings.
396 * @note TextView doesn't store a copy of the given style, it applies the given style to the current text only.
397 * Subsequent calls to SetText() will override any style set by this method.
398 * @param[in] style The given style
399 * @param[in] mask The bit mask.
401 void SetStyleToCurrentText( const TextStyle& style, TextStyle::Mask mask = TextStyle::ALL );
404 * @brief Set the current text alignment.
406 * Default alignment is (HorizontalCenter | VerticalCenter)
407 * @param[in] align The new alignment option.
409 void SetTextAlignment( Alignment::Type align );
412 * @brief Get the current text alignment combined into a single value.
414 * The values can be tested by using the & operator
415 * and the desired flag. e.g. if (GetTextAlignment() & HorizontalCentre) ...
416 * @return the combined alignment
418 Alignment::Type GetTextAlignment() const;
421 * @brief Sets how to wrap the text in lines policy.
423 * @param policy The multi-line policy. \e SplitByNewLineChar is set by default.
425 void SetMultilinePolicy( MultilinePolicy policy );
428 * @brief Gets the wrap in lines policy.
430 * @return The multi-line policy.
432 MultilinePolicy GetMultilinePolicy() const;
435 * @brief Sets how to display the text inside the TextView when it exceeds the text-view's width.
437 * @param policy The exceed policy. Original is set by default.
439 void SetWidthExceedPolicy( ExceedPolicy policy );
442 * @brief Gets the width exceed policy.
444 * @return The exceed policy.
446 ExceedPolicy GetWidthExceedPolicy() const;
449 * @brief Sets how to display the text inside the TextView when it exceeds the text-view's height.
451 * @param policy The exceed policy. Original is set by default.
453 void SetHeightExceedPolicy( ExceedPolicy policy );
456 * @brief Gets the height exceed policy.
458 * @return The exceed policy.
460 ExceedPolicy GetHeightExceedPolicy() const;
463 * @brief Sets how to justify lines inside the text area.
465 * @param justification The line justification. Left is set by default.
467 void SetLineJustification( LineJustification justification );
470 * @brief Gets the line justification.
472 * @return The line justification.
474 LineJustification GetLineJustification() const;
477 * @brief Sets a fade boundary.
481 * @param[in] fadeBoundary The given fade boundary.
483 void SetFadeBoundary( const FadeBoundary& fadeBoundary );
486 * @brief Retrieves the fade boundary.
490 * @return The fade boundary.
492 const FadeBoundary& GetFadeBoundary() const;
495 * @brief Sets the ellipsize text.
497 * @param[in] ellipsizeText The new text. The string may contain style tags. By default the ellipsize text is '...'
499 void SetEllipsizeText( const std::string& ellipsizeText );
502 * @brief Sets the ellipsize text with style.
504 * @param[in] ellipsizeText The new text with its style.
506 void SetEllipsizeText( const MarkupProcessor::StyledTextArray& ellipsizeText );
509 * @brief Retrieves the ellipsize text.
511 * @return The ellipsize text.
513 std::string GetEllipsizeText() const;
516 * @brief A mechanism to retrieve layout information from the TextView.
518 * It produces a vector of CharcterLayoutInfo structures which describe the size and position of each character,
519 * two vectors which maps the logical and visual positions of the characters in a bidirectional text, the size
520 * of the whole laid-out text and the scroll offset value.
522 * @see TextLayoutInfo.
524 * @param[out] textLayoutInfo A structure with text layout information.
526 void GetTextLayoutInfo( TextLayoutInfo& textLayoutInfo );
529 * @brief Allows modification of text-actor's position in the depth sort algorithm.
531 * @see Dali::RenderableActor::SetSortModifier()
532 * @param [in] depthOffset the offset to be given to the internal text-actors. Positive values pushing it further back.
534 void SetSortModifier( float depthOffset );
537 * @brief Sets whether text-view renders text using a previously generated snapshot.
539 * Rendering long text using a snapshot may increase performance. The default value is \e false (render without using a snapshot).
541 * @param[in] enable Whether text-view is using a snapshot to render text.
543 void SetSnapshotModeEnabled( bool enable );
546 * @brief Retrieves whether text-view is using a snapshot to render text.
548 * @return \e true if text-view is using a snapshot to render text, otherwhise it returns \e false.
550 bool IsSnapshotModeEnabled() const;
553 * @brief Sets whether markup processing should be carried out.
555 * To use markup, applications need to SetMarkupProcessingEnabled first, then SetText().
558 * @param[in] enable whether markup processing is carried out or not.
560 void SetMarkupProcessingEnabled( bool enable );
563 * @brief Retrieves whether text-view is processing markup text
565 * @return \e true if text-view markup processing is enabled, otherwhise it returns \e false.
567 bool IsMarkupProcessingEnabled() const;
570 * @brief Enables or disables the text scroll.
572 * When scroll is enabled, snapshot mode will be enabled automatically. Equally, if scroll is disabled
573 * the snapshot mode is restored to the previous value.
575 * @param[in] enable Whether to enable the text scroll.
577 void SetScrollEnabled( bool enable );
580 * @brief Retrieves whether the text scroll is enabled.
582 * @return \e true if the scroll is enabled.
584 bool IsScrollEnabled() const;
587 * @brief Sets a new scroll position.
589 * The new scroll position set could be trimmed if the text doesn't cover the whole text-view.
590 * i.e. If a text-view is 100x100 and a text is 200x100 a scroll position beyond 50x0 will be trimmed to 50x0.
592 * Call IsScrollPositionTrimmed() to know if the last scroll position set has been trimmed.
594 * A signal is emitted. @see ScrolledSignal().
596 * @param[in] position The new scroll position.
598 void SetScrollPosition( const Vector2& position );
601 * @brief Recrieves current scroll position.
603 * @return The scroll position.
605 const Vector2& GetScrollPosition() const;
608 * @brief Whether the last scroll position set was trimmed.
610 * @return \e true if the last scroll position set was trimmed, otherwise \e false.
612 bool IsScrollPositionTrimmed() const;
615 /// @brief Signal types
616 typedef SignalV2< void ( TextView textView, Vector2 scrollDelta ) > ScrolledSignalV2;
619 * @brief Signal emitted when the text is scrolled inside the text-view.
621 * A callback with the following prototype can be connected to this signal.
623 * Callback(TextView textView, Vector2 scrollDelta)
625 * \e textView is the handle of the text-view emitting the signal.
626 * \e scrollDelta is the differente of the current scroll position with the previous one.
627 * @return The signal to connect to
629 ScrolledSignalV2& ScrolledSignal();
631 public: // Not intended for application developers
634 * @brief Creates a handle using the Toolkit::Internal implementation.
635 * @note Not intended for application developers
637 * @param[in] implementation The Control implementation.
639 TextView( Internal::TextView& implementation );
642 * @brief Allows the creation of this Control from an Internal::CustomActor pointer.
643 * @note Not intended for application developers
645 * @param[in] internal A pointer to the internal CustomActor.
647 TextView( Dali::Internal::CustomActor* internal );
650 } // namespace Toolkit
654 #endif // __DALI_TOOLKIT_ITEM_VIEW_H__