RedcrabX – TextBox Guide
Rich-text annotations on the worksheet | Version 1.0
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Table of Contents
1. Overview
The TextBox is a free-form rich-text annotation that lives on the worksheet
canvas next to your math, charts, and images. It is based on a WPF RichTextBox,
so each character can have its own font, size, style, and color.
Typical use cases:
- Headings and section titles between groups of MathBoxes
- Explanatory comments next to a calculation
- Notes, conclusions, and references
- Captions for charts, plots, or images
2. Inserting and Editing
- Click the Text button in the ribbon. A new TextBox appears on the canvas with the placeholder content “Enter text”.
- Click into the box to enter edit mode and start typing.
- Press Enter to start a new paragraph – the box grows automatically and a vertical scrollbar appears once the content exceeds the box height.
- Click outside the box (or press Esc) to leave edit mode.
Note: The TextBox accepts plain typing, line breaks, and standard Windows
text-editing shortcuts (Ctrl+A,
Ctrl+C,
Ctrl+V,
Ctrl+X).
3. Formatting Works on the Selection
All formatting commands (font, size, bold, color, alignment, …) apply only to the
currently selected text. To change formatting:
- Click into the TextBox.
- Select the characters or paragraphs you want to format (drag with the mouse, or use Shift+arrow keys).
- Click the desired formatting button in the status toolbar at the bottom of the window.
Tip: Use Ctrl+A
to select the entire content of the TextBox, then apply formatting to all text at once.
4. Font Family, Size and Style
When a TextBox is selected, the status toolbar shows three combo boxes:
| Control | Description |
|---|
| Font family | Lists every system font. Supports type-ahead search – just type the first letters of the font name. |
| Font size | Editable combo with presets 8, 9, 10, 11, 12, 14, 16, 18, 20, 24, 28, 32 pt. You can type any number directly. |
| Font style | Choose Normal, Italic, or Oblique. This sets the default style of the entire TextBox. |
Default font: A new TextBox starts with the system default font at 12 pt.
Default Paragraph margins are removed so consecutive lines have no extra spacing.
5. Bold, Italic, Underline
Three toggle buttons after the font-style combo box let you apply character formatting:
| Button | Effect |
|---|
| B | Toggles bold on/off for the selection |
| I | Toggles italic on/off for the selection |
| U | Toggles underline on/off for the selection |
Click a toggle button to apply, click again to remove. The buttons can be combined freely
(e.g. bold + italic + underline).
6. Text Alignment
Three alignment buttons control horizontal alignment of the paragraph that contains the cursor or selection:
| Button | Alignment |
|---|
| Left icon | Left-aligned (default) |
| Center icon | Centered |
| Right icon | Right-aligned |
Note: Alignment is a paragraph-level property. To align several paragraphs
at once, select all of them before clicking the alignment button.
7. Foreground and Background Color
Two color buttons in the status toolbar open the standard Windows color picker:
| Button | Description |
|---|
| Font color | Changes the text color of the selection. A small swatch on the button shows the currently chosen color. |
| Background color | Changes the highlight color behind the selected characters (similar to a marker pen). |
Pick a custom color, click OK, and the selection is recolored immediately. The
swatch on the toolbar button updates to remember your last choice.
Tip: Use a colored background for warnings (yellow) or
important results (green). Combine with bold for maximum visibility.
8. Undo and Redo
The status toolbar contains Undo and Redo buttons, which are
enabled or disabled depending on the available history of the editor.
| Action | Shortcut |
|---|
| Undo last edit | Ctrl+Z |
| Redo last undone edit | Ctrl+Y |
The undo stack tracks both text changes and formatting changes (bold, color, alignment, …).
9. Moving and Resizing
- Click the TextBox border (outside the editor area) to select the box without entering edit mode.
- Drag the box to reposition it on the canvas.
- Drag the bottom-right resize handle to change the box size.
- If the content does not fit, vertical and horizontal scrollbars appear automatically.
- Press Del while the box is selected (and edit mode is off) to remove it.
10. Saving with the Worksheet
When the worksheet is saved (Ctrl+S),
the full rich-text content of every TextBox is written into the worksheet file
including all character and paragraph formatting (font, size, weight, style, decorations,
colors, and alignment). On reopen, the TextBox is restored exactly as it was.
11. Tips and Best Practices
- Headings: Use a larger font size (16–20 pt) and bold to clearly mark section breaks in your worksheet.
- Inline equations: The TextBox does not render math formulas – place a MathBox next to it for actual computations and use the TextBox for explanations.
- Color coding: Reserve a single accent color (e.g. blue) for all results and another (e.g. red) for warnings throughout the worksheet to keep visual consistency.
- Group with other boxes: Combine TextBox + ChartBox or TextBox + ImageBox to create captioned figures.
- Print preview: The TextBox prints exactly as it appears on the canvas. Use Ctrl+P to verify font sizes and line breaks before printing.
- Copy formatting from another app: Pasting from Word, Outlook or a browser keeps most formatting (bold, italic, color); pasting from Notepad inserts plain text only.