Merge pull request #2551 from myk002/myk_insert

refactor EditField text insertion

docs/dev/Lua API.rst

@@ -4350,6 +4350,23 @@ following keyboard hotkeys:
 - Ctrl-B/Ctrl-F: move the cursor one word back or forward.
 - Ctrl-A/Ctrl-E: move the cursor to the beginning/end of the text.
 
+The ``EditField`` class also provides the following functions:
+
+* ``editfield:setCursor([cursor_pos])``
+
+  Sets the text insert cursor to the specified position. If ``cursor_pos`` is
+  not specified or is past the end of the current text string, the cursor will
+  be set to the end of the current input (that is, ``#editfield.text + 1``).
+
+* ``editfield:setText(text[, cursor_pos])``
+
+  Sets the input text string and, optionally, the cursor position. If the
+  cursor position is not specified, it sets it to the end of the string.
+
+* ``editfield:insert(text)``
+
+  Inserts the given text at the current cursor position.
+
 Scrollbar class
 ---------------
 

library/lua/gui/widgets.lua

@@ -657,6 +657,12 @@ function EditField:onRenderBody(dc)
     dc:string((' '):rep(dc.clip_x2 - dc.x))
 end
 
+function EditField:insert(text)
+    local old = self.text
+    self:setText(old:sub(1,self.cursor-1)..text..old:sub(self.cursor),
+                 self.cursor + #text)
+end
+
 function EditField:onInput(keys)
     if not self.focus then
         -- only react to our hotkey
@@ -713,8 +719,7 @@ function EditField:onInput(keys)
         else
             local cv = string.char(keys._STRING)
             if not self.on_char or self.on_char(cv, old) then
-                self:setText(old:sub(1,self.cursor-1)..cv..old:sub(self.cursor),
-                             self.cursor + 1)
+                self:insert(cv)
             elseif self.on_char then
                 return self.modal
             end