1 // Copyright 2019 Google LLC. 2 #ifndef ParagraphBuilder_DEFINED 3 #define ParagraphBuilder_DEFINED 4 5 #include <memory> 6 #include <stack> 7 #include <string> 8 #include <tuple> 9 #include "modules/skparagraph/include/FontCollection.h" 10 #include "modules/skparagraph/include/Paragraph.h" 11 #ifdef OHOS_SUPPORT 12 #include "modules/skparagraph/include/ParagraphLineFetcher.h" 13 #endif 14 #include "modules/skparagraph/include/ParagraphStyle.h" 15 #include "modules/skparagraph/include/TextStyle.h" 16 #include "modules/skunicode/include/SkUnicode.h" 17 18 namespace skia { 19 namespace textlayout { 20 21 class ParagraphBuilder { 22 public: ParagraphBuilder(const ParagraphStyle &,sk_sp<FontCollection>)23 ParagraphBuilder(const ParagraphStyle&, sk_sp<FontCollection>) { } 24 25 virtual ~ParagraphBuilder() = default; 26 27 // Push a style to the stack. The corresponding text added with AddText will 28 // use the top-most style. 29 virtual void pushStyle(const TextStyle& style) = 0; 30 31 // Remove a style from the stack. Useful to apply different styles to chunks 32 // of text such as bolding. 33 // Example: 34 // builder.PushStyle(normal_style); 35 // builder.AddText("Hello this is normal. "); 36 // 37 // builder.PushStyle(bold_style); 38 // builder.AddText("And this is BOLD. "); 39 // 40 // builder.Pop(); 41 // builder.AddText(" Back to normal again."); 42 virtual void pop() = 0; 43 44 virtual TextStyle peekStyle() = 0; 45 46 // Adds UTF16-encoded text to the builder. Forms the proper runs to use the upper-most style 47 // on the style_stack. 48 virtual void addText(const std::u16string& text) = 0; 49 50 // Adds UTF8-encoded text to the builder, using the top-most style on the style_stack. 51 virtual void addText(const char* text) = 0; 52 virtual void addText(const char* text, size_t len) = 0; 53 54 // Pushes the information required to leave an open space, where Flutter may 55 // draw a custom placeholder into. 56 // Internally, this method adds a single object replacement character (0xFFFC) 57 virtual void addPlaceholder(const PlaceholderStyle& placeholderStyle) = 0; 58 59 // Constructs a SkParagraph object that can be used to layout and paint the text to a SkCanvas. 60 virtual std::unique_ptr<Paragraph> Build() = 0; 61 62 #ifdef OHOS_SUPPORT 63 virtual std::unique_ptr<ParagraphLineFetcher> buildLineFetcher() = 0; 64 #endif 65 virtual SkSpan<char> getText() = 0; 66 virtual const ParagraphStyle& getParagraphStyle() const = 0; 67 68 // Mainly, support for "Client" unicode 69 virtual void setWordsUtf8(std::vector<SkUnicode::Position> wordsUtf8) = 0; 70 virtual void setWordsUtf16(std::vector<SkUnicode::Position> wordsUtf16) = 0; 71 72 virtual void setGraphemeBreaksUtf8(std::vector<SkUnicode::Position> graphemesUtf8) = 0; 73 virtual void setGraphemeBreaksUtf16(std::vector<SkUnicode::Position> graphemesUtf16) = 0; 74 75 virtual void setLineBreaksUtf8(std::vector<SkUnicode::LineBreakBefore> lineBreaksUtf8) = 0; 76 virtual void setLineBreaksUtf16(std::vector<SkUnicode::LineBreakBefore> lineBreaksUtf16) = 0; 77 78 virtual void SetUnicode(std::unique_ptr<SkUnicode> unicode) = 0; 79 80 // Resets this builder to its initial state, discarding any text, styles, placeholders that have 81 // been added, but keeping the initial ParagraphStyle. 82 virtual void Reset() = 0; 83 84 // Just until we fix all the google3 code 85 static std::unique_ptr<ParagraphBuilder> make(const ParagraphStyle& style, 86 sk_sp<FontCollection> fontCollection); 87 }; 88 } // namespace textlayout 89 } // namespace skia 90 91 #endif // ParagraphBuilder_DEFINED 92