refactor(statistics): avoid magic 0.1 schedule with PostRender event

frontend/apps/reader/readerui.lua

@@ -259,11 +259,14 @@ function ReaderUI:init()
         self:registerPostInitCallback(function()
             self.document:loadDocument()
 
-            -- read additional settings after the document has been loaded
-            -- (but not rendered yet)
+            -- used to read additional settings after the document has been
+            -- loaded (but not rendered yet)
             self:handleEvent(Event:new("PreRenderDocument", self.doc_settings))
 
             self.document:render()
+
+            -- CREngine only reports correct page count after rendering is done
+            self:handleEvent(Event:new("PostRenderDocument", self.doc_settings))
         end)
         -- typeset controller
         self:registerModule("typeset", ReaderTypeset:new{

plugins/statistics.koplugin/main.lua

@@ -58,9 +58,7 @@ function ReaderStatistics:initData(config)
     if self.is_enabled then
         local book_properties = self:getBookProperties()
         self:savePropertiesInToData(book_properties)
-        if config.data.stats then
-            self.data = config.data.stats
-        else
+        if not self.data then
            --first time merge data
             self:inplaceMigration();
         end
@@ -490,9 +488,12 @@ function ReaderStatistics:saveSettings(fields)
 end
 
 function ReaderStatistics:onReadSettings(config)
-    -- delay initialization for accurate total pages count of the doc
-    UIManager:scheduleIn(0.1, function() self:initData(config) end)
+    self.data = config.data.stats
 end
 
-return ReaderStatistics
+function ReaderStatistics:onPostRenderDocument()
+    -- we have correct page count now, do the actual initialization work
+    self:initData()
+end
 
+return ReaderStatistics