# TMX Editor - Treeview Grid with Resizable Columns ✓

## Updates Complete

The TMX Editor now uses a **Treeview widget** which provides:

1. ✅ **Resizable columns** - Drag column borders to adjust width
2. ✅ **Row selection** - Click to select individual segments
3. ✅ **Integrated edit panel** - Edit above the grid (no popups)
4. ✅ **Professional grid interface** - Like Excel/Calc

## Key Features

### Resizable Columns
- **Drag the borders** between column headers to resize
- **Source column** - Adjust to see full source text
- **Target column** - Adjust to see full target text
- **ID column** - Fixed width (60px) for reference
- Column widths persist during session

### Row Selection
- **Single-click** - Select a row (loads into edit panel)
- **Double-click** - Select and focus on target text for quick editing
- **Right-click** - Context menu (Edit, Refresh)
- **Keyboard navigation** - Arrow keys to move between rows
- Selected row is highlighted with blue background

### Visual Feedback
- **Matching rows** - Light yellow background (`#fffacd`) for filtered results
- **Selected row** - Blue highlight (system default)
- **Hover effect** - Visual feedback when hovering over rows
- **Column headers** - Show language codes (e.g., "Source (en-US)")

### Integrated Edit Panel
Located **above the grid**:
- **Auto-loads** when you click a segment
- **Source text** (left) - Shows original text
- **Target text** (right) - Edit translations here
- **Save Changes** - Updates TMX and refreshes grid
- **Cancel** - Discards changes and clears panel
- **Status label** - Shows which TU you're editing (e.g., "Editing TU #123")

## Usage Examples

### Resize Columns
1. Move mouse to column border in header
2. Cursor changes to resize cursor (↔)
3. Click and drag left/right
4. Release to set new width

### Select and Edit
1. **Click** any row to select it
2. Row highlights in blue
3. Segment loads into edit panel above
4. Edit source or target text
5. Click **💾 Save Changes**
6. Grid refreshes to show updated text

### Quick Edit Workflow
1. **Double-click** a segment
2. Target text box gets focus automatically
3. Start typing immediately
4. Press Tab to move between fields
5. Click Save when done

### Filter and Highlight
1. Enter search term in Source or Target filter
2. Click **Apply Filter**
3. Matching rows show in **light yellow**
4. Click a yellow row to edit it
5. Edit panel shows full text (not truncated)

## Technical Implementation

### Widget Type
```python
# Treeview with resizable columns
self.tree = ttk.Treeview(grid_container, 
                        columns=('ID', 'Source', 'Target'),
                        show='headings',
                        selectmode='browse')

# Configure columns (user can resize)
self.tree.column('ID', width=60, anchor='center', stretch=False)
self.tree.column('Source', width=500, anchor='w', stretch=True)
self.tree.column('Target', width=500, anchor='w', stretch=True)
```

### Row Highlighting
```python
# Configure tag for matching rows
self.tree.tag_configure('match', background='#fffacd')

# Insert with tag if matches filter
if filter_matches:
    item_id = self.tree.insert('', 'end', 
                              values=(id, src, tgt), 
                              tags=('match',))
```

### Event Handlers
```python
# Single-click: Select and load into edit panel
self.tree.bind('<<TreeviewSelect>>', self.on_tree_select)

# Double-click: Load and focus target for editing
self.tree.bind('<Double-Button-1>', self.on_tree_double_click)

# Right-click: Context menu
self.tree.bind('<Button-3>', self.show_context_menu)
```

### TU Mapping
```python
# Map tree items to TU objects
self.tu_item_map = {}  # item_id -> TU object

# Store when inserting
item_id = self.tree.insert('', 'end', values=(...))
self.tu_item_map[item_id] = tu

# Retrieve when selecting
selected = self.tree.selection()[0]
tu = self.tu_item_map[selected]
```

## Benefits

### User Experience
1. **Familiar interface** - Works like Excel or spreadsheet
2. **Adjustable layout** - Resize columns to see what you need
3. **Direct selection** - Click to select, double-click to edit
4. **No popups** - Everything in one integrated view
5. **Fast navigation** - Keyboard and mouse both work

### Professional Features
1. **Standard grid controls** - Matches industry expectations
2. **Visual feedback** - Clear selection and highlighting
3. **Flexible columns** - User controls the layout
4. **Integrated editing** - Edit without losing context
5. **Keyboard shortcuts** - Tab, arrows, Enter all work

### Workflow Improvements
**Before (Text widget):**
- ❌ No column resizing
- ❌ No row selection
- ❌ Text-based navigation only
- ❌ Hard to see structure

**After (Treeview):**
- ✅ Drag to resize columns
- ✅ Click to select rows
- ✅ Mouse and keyboard navigation
- ✅ Clear grid structure
- ✅ Professional appearance

## Comparison with Professional TMX Editors

### Heartsome TMX Editor
- Grid: ✅ Resizable columns
- Selection: ✅ Row selection
- Editing: ⚠️ Popup dialogs
- Highlighting: ⚠️ Row-level only

### Supervertaler TMX Editor
- Grid: ✅ Resizable columns (Treeview)
- Selection: ✅ Row selection + keyboard
- Editing: ✅ Integrated panel (no popups!)
- Highlighting: ✅ Row highlighting for matches + word-level in edit panel

## Color Scheme

- **Edit panel background**: `#e8f4f8` (light blue)
- **Match highlight**: `#fffacd` (light yellow - lemon chiffon)
- **Selected row**: System default (blue)
- **Grid background**: White
- **Header background**: Light gray
- **Save button**: `#4CAF50` (green)
- **Cancel button**: `#f44336` (red)

## Known Features

### What Works
- ✅ Column resizing (drag borders)
- ✅ Row selection (click)
- ✅ Double-click to edit
- ✅ Keyboard navigation
- ✅ Context menu (right-click)
- ✅ Matching row highlighting
- ✅ Integrated edit panel
- ✅ Save/Cancel buttons
- ✅ Pagination (50 TUs/page)
- ✅ Language filtering

### Current Design Decisions
- Row-level highlighting (not word-level in grid) - matches Heartsome approach
- Word-level highlighting available in edit panel when you select a row
- This is more performant and clearer than trying to highlight individual words in grid cells

---

**Version**: 3.7.5  
**Date**: October 25, 2025  
**Module**: `modules/tmx_editor.py`  
**Widget**: Tkinter Treeview (professional grid control)  
**Features**: Resizable columns, row selection, integrated editing  
**Status**: ✓ Production Ready
