Two-Way Tools: Designer ↔ Code Sync

HarbourBuilder's Two-Way Tools engine ensures that your visual form design and your source code are always perfectly synchronized. Every change you make in the visual Form Designer is immediately reflected in the generated code, and every structural change you make to the code is instantly visible in the designer.

How It Works

When you work in the Form Designer, every action — dropping a control, resizing, moving, changing a property — triggers a targeted code regeneration. The engine parses your existing source file, identifies the UI definition sections, updates them, and leaves everything else intact.

What Gets Regenerated

The code engine identifies and updates only these categories:

Before and After: Code Regeneration

Before: You drop a button in the designer

CLASS TForm1 FROM TForm

   DATA oBtn1

   METHOD CreateForm()
   METHOD OnBtnClick()

ENDCLASS

METHOD CreateForm() CLASS TForm1
   ::cTitle  := "Form1"
   ::nWidth  := 400
   ::nHeight := 300
return nil

METHOD OnBtnClick() CLASS TForm1
   // Your custom logic - PRESERVED
   MsgInfo( "Button clicked!" )
return nil

After: Code regenerated (button added, method untouched)

CLASS TForm1 FROM TForm

   DATA oBtn1

   METHOD CreateForm()
   METHOD OnBtnClick()

ENDCLASS

METHOD CreateForm() CLASS TForm1
   ::cTitle  := "Form1"
   ::nWidth  := 400
   ::nHeight := 300

   // --- NEW: Button added by designer ---
   @ 120, 140 BUTTON ::oBtn1 PROMPT "Button1" ;
      OF Self SIZE 120, 32 ;
      ACTION ::OnBtnClick()
return nil

METHOD OnBtnClick() CLASS TForm1
   // Your custom logic - PRESERVED
   MsgInfo( "Button clicked!" )
return nil

Workflow

Code Parsing Rules

The regeneration engine uses these rules to identify safe-to-modify sections:

1. CLASS / ENDCCLASS blocks — DATA and METHOD declarations are updated; existing METHOD bodies are skipped.
2. DEFINE FORM blocks — Properties within DEFINE blocks are regenerated.
3. @ POSITION statements — Position, size, and property clauses are updated.
4. ACTIVATE FORM blocks — Activation clauses are regenerated.
5. Everything else — Static functions, METHOD bodies, comments, and custom code are left untouched.

Handling Conflicts

If you manually edit a line that the designer also manages (e.g., changing a button's position in code while it's also on the form canvas), the designer's view takes precedence on the next regeneration. To avoid conflicts:

• Use the Object Inspector to change properties rather than editing code directly.
• Use the Designer canvas to move and resize controls.
• Use the Code Editor only for METHOD implementations, event handlers, and custom functions.

Recent Improvements

The Two-Way Tools engine has been enhanced with several important improvements:

Improved Code Generation

• Automatic launcher placement: The FUNCTION FormN() launcher is now placed at the very end of generated files, after user methods, to prevent duplicate function definitions.
• Better method preservation: User method implementations are properly preserved during code regeneration cycles.
• Duplicate header stripping: Duplicate #include "hbbuilder.ch" and #include "classes.prg" statements are automatically removed to prevent linker errors.

Build System Enhancements

• Separator stripping: "----" separators are automatically stripped from form files before assembly to prevent Harbour parse errors.
• Improved project loading: The UI_FormCreateChildren() function ensures all deferred controls get proper Win32 handles after project loading.

New Property Support

• lTransparent for TLabel: Labels can now have transparent backgrounds, allowing form colors to show through.
• RGB() function: Added to classes.prg for creating color values from red, green, and blue components.

Switching Between Views

Use the toolbar toggle or keyboard shortcut to switch between Designer and Code views: