FileBrowser: change page to show last file or previous subdir (#3351)

When going from reader to filemanager, we are in the directory
containing the last_file. With this, we will also be on the page
showing this file.
When in filemanager and going up (".."), we will also be on the
page containing the directory we came from.

frontend/apps/filemanager/filemanager.lua

@@ -317,7 +317,7 @@ function FileManager:init()
     self:handleEvent(Event:new("SetDimensions", self.dimen))
 end
 
-function FileManager:reinit(path)
+function FileManager:reinit(path, focused_file)
     self.dimen = Screen:getSize()
     -- backup the root path and path items
     self.root_path = path or self.file_chooser.path
@@ -329,6 +329,9 @@ function FileManager:reinit(path)
     self:init()
     self.file_chooser.path_items = path_items_backup
     self:onRefresh()
+    if focused_file then
+        self.file_chooser:changePageToPath(focused_file)
+    end
 end
 
 function FileManager:toggleHiddenFiles()
@@ -547,7 +550,7 @@ function FileManager:getStartWithMenuTable()
     }
 end
 
-function FileManager:showFiles(path)
+function FileManager:showFiles(path, focused_file)
     path = path or G_reader_settings:readSetting("lastdir") or filemanagerutil.getDefaultDir()
     G_reader_settings:saveSetting("lastdir", path)
     restoreScreenMode()
@@ -558,6 +561,9 @@ function FileManager:showFiles(path)
             self.instance = nil
         end
     }
+    if focused_file then
+        file_manager.file_chooser:changePageToPath(focused_file)
+    end
     UIManager:show(file_manager)
     self.instance = file_manager
 end

frontend/apps/reader/readerui.lua

@@ -365,16 +365,16 @@ end
 function ReaderUI:showFileManager()
     local FileManager = require("apps/filemanager/filemanager")
     local QuickStart = require("ui/quickstart")
-    local lastdir
+    local last_dir
     local last_file = G_reader_settings:readSetting("lastfile")
     -- ignore quickstart guide as last_file so we can go back to home dir
     if last_file and last_file ~= QuickStart.quickstart_filename then
-        lastdir = last_file:match("(.*)/")
+        last_dir = last_file:match("(.*)/")
     end
     if FileManager.instance then
-        FileManager.instance:reinit(lastdir)
+        FileManager.instance:reinit(last_dir, last_file)
     else
-        FileManager:showFiles(lastdir)
+        FileManager:showFiles(last_dir, last_file)
     end
 end
 

frontend/ui/widget/filechooser.lua

@@ -175,7 +175,8 @@ function FileChooser:genItemTableFromPath(path)
         table.insert(item_table, {
             text = dir.name == ".." and  "⬆ ../" or dir.name.."/",
             mandatory = istr,
-            path = subdir_path
+            path = subdir_path,
+            is_go_up = dir.name == ".."
         })
     end
 
@@ -230,13 +231,29 @@ function FileChooser:refreshPath()
     self:switchItemTable(nil, self:genItemTableFromPath(self.path), self.path_items[self.path])
 end
 
-function FileChooser:changeToPath(path)
+function FileChooser:changeToPath(path, focused_path)
     path = util.realpath(path)
     self.path = path
     self:refreshPath()
+    if focused_path then
+        self:changePageToPath(focused_path)
+    end
     self:onPathChanged(path)
 end
 
+function FileChooser:changePageToPath(path)
+    if not path then return end
+    for num, item in ipairs(self.item_table) do
+        if item.path == path then
+            local page = math.floor((num-1) / self.perpage) + 1
+            if page ~= self.page then
+                self:onGotoPage(page)
+            end
+            break
+        end
+    end
+end
+
 function FileChooser:toggleHiddenFiles()
     self.show_hidden = not self.show_hidden
     self:refreshPath()
@@ -258,7 +275,7 @@ function FileChooser:onMenuSelect(item)
     if lfs.attributes(item.path, "mode") == "file" then
         self:onFileSelect(item.path)
     else
-        self:changeToPath(item.path)
+        self:changeToPath(item.path, item.is_go_up and self.path)
     end
     return true
 end