InputDialog: add 'Go to line' button (#7673)

frontend/ui/widget/container/inputcontainer.lua

@@ -266,6 +266,9 @@ function InputContainer:onGesture(ev)
             end
         end
     end
+    if self.stop_events_propagation then
+        return true
+    end
 end
 
 function InputContainer:onInput(input, ignore_first_hold_release)

frontend/ui/widget/inputdialog.lua

@@ -115,6 +115,7 @@ local UIManager = require("ui/uimanager")
 local VerticalGroup = require("ui/widget/verticalgroup")
 local VerticalSpan = require("ui/widget/verticalspan")
 local Screen = Device.screen
+local T = require("ffi/util").template
 local _ = require("gettext")
 
 local InputDialog = InputContainer:new{
@@ -723,6 +724,46 @@ function InputDialog:_addScrollButtons(nav_bar)
                 end,
             })
         end
+        -- Add a button to go to the line by its number in the file
+        if self.fullscreen then
+            table.insert(row, {
+                text = _("Go"),
+                callback = function()
+                    local cur_line_num, last_line_num = self._input_widget:getLineNums()
+                    local input_dialog
+                    input_dialog = InputDialog:new{
+                        title = _("Enter line number"),
+                        -- @translators %1 is the current line number, %2 is the last line number
+                        input_hint = T(_("%1 (1 - %2)"), cur_line_num, last_line_num),
+                        input_type = "number",
+                        stop_events_propagation = true, -- avoid interactions with upper InputDialog
+                        buttons = {
+                            {
+                                {
+                                    text = _("Cancel"),
+                                    callback = function()
+                                        UIManager:close(input_dialog)
+                                    end,
+                                },
+                                {
+                                    text = _("Go to line"),
+                                    is_enter_default = true,
+                                    callback = function()
+                                        local new_line_num = tonumber(input_dialog:getInputText())
+                                        if new_line_num and new_line_num >= 1 and new_line_num <= last_line_num then
+                                            UIManager:close(input_dialog)
+                                            self._input_widget:moveCursorToCharPos(self._input_widget:getLineCharPos(new_line_num))
+                                        end
+                                    end,
+                                },
+                            },
+                        },
+                    }
+                    UIManager:show(input_dialog)
+                    input_dialog:onShowKeyboard()
+                end,
+            })
+        end
         table.insert(row, {
             text = "⇱",
             id = "top",

frontend/ui/widget/inputtext.lua

@@ -501,6 +501,38 @@ function InputText:getKeyboardDimen()
     return self.keyboard.dimen
 end
 
+-- calculate current and last (original) line numbers
+function InputText:getLineNums()
+    local cur_line_num, last_line_num = 1, 1
+    for i = 1, #self.charlist do
+        if self.text_widget.charlist[i] == "\n" then
+            if i < self.charpos then
+                cur_line_num = cur_line_num + 1
+            end
+            last_line_num = last_line_num + 1
+        end
+    end
+    return cur_line_num, last_line_num
+end
+
+-- calculate charpos for the beginning of (original) line
+function InputText:getLineCharPos(line_num)
+    local char_pos = 1
+    if line_num > 1 then
+        local j = 1
+        for i = 1, #self.charlist do
+            if self.charlist[i] == "\n" then
+                j = j + 1
+                if j == line_num then
+                    char_pos = i + 1
+                    break
+                end
+            end
+        end
+    end
+    return char_pos
+end
+
 function InputText:addChars(chars)
     if not chars then
         -- VirtualKeyboard:addChar(key) gave us 'nil' once (?!)
@@ -578,6 +610,11 @@ function InputText:goToEnd()
     self.text_widget:moveCursorToCharPos(0)
 end
 
+function InputText:moveCursorToCharPos(char_pos)
+    self.text_widget:moveCursorToCharPos(char_pos)
+    self.charpos, self.top_line_num = self.text_widget:getCharPos()
+end
+
 function InputText:upLine()
     self.text_widget:moveCursorUp()
     self.charpos, self.top_line_num = self.text_widget:getCharPos()