IssueNo:https://gitee.com/openharmony/graphic_ui/issues/I3YPUS

Description:add file offset interface
Sig:graphic
Feature or Bugfix:Bugfix
Binary Source:No
Signed-off-by: Nwangtiantian <wangtiantian19@huawei.com>

frameworks/font/ui_font_bitmap.cpp

@@ -28,7 +28,7 @@
 #endif
 
 namespace OHOS {
-UIFontBitmap::UIFontBitmap() : dynamicFont_(), dynamicFontRamUsed_(0), dynamicFontFd_(-1)
+UIFontBitmap::UIFontBitmap() : dynamicFont_(), dynamicFontRamUsed_(0), dynamicFontFd_(-1), offset_(0)
 {
     SetBaseFontId(UIFontBuilder::GetInstance()->GetBitmapFontIdMax());
     bitmapCache_ = nullptr;
@@ -91,8 +91,7 @@ int8_t UIFontBitmap::SetFontPath(const char* dpath, const char* spath)
         return INVALID_RET_VALUE;
     }
     dynamicFont_.SetRamBuffer(GetRamAddr());
-    uint32_t start = 0;
-    int32_t ret = dynamicFont_.SetFile(dynamicFontFd_, start);
+    int32_t ret = dynamicFont_.SetFile(dynamicFontFd_, offset_);
     if (ret == INVALID_RET_VALUE) {
         GRAPHIC_LOGE("GlyphsManager::SetFile failed");
         close(dynamicFontFd_);
@@ -308,4 +307,9 @@ int16_t UIFontBitmap::GetWidthInFontId(uint32_t unicode, uint8_t fontId)
     }
     return GetDynamicFontWidth(unicode, GetBaseFontId());
 }
+
+void UIFontBitmap::SetFontFileOffset(uint32_t offset)
+{
+    offset_ = offset;
+}
 } // namespace

interfaces/innerkits/font/ui_font_bitmap.h

@@ -41,6 +41,7 @@ public:
     int8_t GetFontVersion(char* dVersion, uint8_t dLen, char* sVersion, uint8_t sLen) const override;
     int8_t SetCurrentLangId(uint8_t langId) override;
     UITextLanguageFontParam* GetFontInfo(uint8_t fontId) const override;
+    void SetFontFileOffset(uint32_t offset) override;
 
 protected:
     uint32_t GetBitmapRamUsed();
@@ -65,6 +66,7 @@ private:
     uint32_t bitmapRamUsed_;
     UIFontCache* bitmapCache_;
     int32_t dynamicFontFd_;
+    uint32_t offset_;
 };
 } // namespce OHOS
 #endif // UI_FONT_BITMAP_H
\ No newline at end of file

interfaces/kits/font/base_font.h

@@ -201,6 +201,8 @@ public:
         return 0;
     }
 
+    virtual void SetFontFileOffset(uint32_t offset) {}
+
     /**
      * @brief Get current font id
      *

interfaces/kits/font/ui_font.h

@@ -223,6 +223,11 @@ public:
     static UIFont* GetInstance();
     void SetFont(BaseFont* font);
 
+    void SetFontFileOffset(uint32_t offset)
+    {
+        instance_->SetFontFileOffset(offset);
+    }
+
 private:
     UIFont();
     /**