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 #include "modules/skparagraph/include/ParagraphStyle.h" 12 #include "modules/skparagraph/include/TextStyle.h" 13 14 namespace skia { 15 namespace textlayout { 16 17 class ParagraphBuilder { 18 public: ParagraphBuilder(const ParagraphStyle & style,sk_sp<FontCollection> fontCollection)19 ParagraphBuilder(const ParagraphStyle& style, sk_sp<FontCollection> fontCollection) { } 20 21 virtual ~ParagraphBuilder() = default; 22 23 // Push a style to the stack. The corresponding text added with AddText will 24 // use the top-most style. 25 virtual void pushStyle(const TextStyle& style) = 0; 26 27 // Remove a style from the stack. Useful to apply different styles to chunks 28 // of text such as bolding. 29 // Example: 30 // builder.PushStyle(normal_style); 31 // builder.AddText("Hello this is normal. "); 32 // 33 // builder.PushStyle(bold_style); 34 // builder.AddText("And this is BOLD. "); 35 // 36 // builder.Pop(); 37 // builder.AddText(" Back to normal again."); 38 virtual void pop() = 0; 39 40 virtual TextStyle peekStyle() = 0; 41 42 // Adds text to the builder. Forms the proper runs to use the upper-most style 43 // on the style_stack_; 44 virtual void addText(const std::u16string& text) = 0; 45 46 // Converts to u16string before adding. 47 virtual void addText(const char* text) = 0; 48 49 virtual void setParagraphStyle(const ParagraphStyle& style) = 0; 50 51 // Constructs a SkParagraph object that can be used to layout and paint the text to a SkCanvas. 52 virtual std::unique_ptr<Paragraph> Build() = 0; 53 54 static std::unique_ptr<ParagraphBuilder> make(const ParagraphStyle& style, 55 sk_sp<FontCollection> fontCollection); 56 }; 57 } // namespace textlayout 58 } // namespace skia 59 60 #endif // ParagraphBuilder_DEFINED 61