To open the Symbol Editor, press the Symbol button in the corresponding Object, Relationship, or Role Tool (in the Port Tool, the Symbol button is disabled as Ports do not have their own symbols). You can also open the Symbol Editor for a type from almost any place where that type is displayed in a list, by selecting Edit Symbol from the type’s pop-up menu. In a Graph Tool’s Types tab and Bindings tab, and in the Diagram Editor sidebar in the tree view or the top row of the property sheet, Shift-double-clicking the type will also work.

As a result of any of the above, a Symbol Editor opens showing the symbol of that type as in Figure 3–1 (if no symbol has yet been defined for the type, the editor will initially be empty).

The Symbol Editor window can be divided into five parts. The usual menu bar can be found from the top of the window. Below the menu bar, there is a toolbar with action buttons for Save, Cut, Copy, Paste, Undo, Redo and Zoom commands (Set Zoom, Default Zoom and Zoom to Fit), as well as the tool buttons for creating various symbol element shapes. The largest part of the window, the drawing area that contains the symbol elements, lies in the middle. At the bottom of the window, there is a formatting bar for symbol element properties like color, line style and weight, and a status bar showing information about the currently selected elements and grid and zoom settings.

If the Symbol Editor is opened for a type that has an existing symbol, the symbol is automatically loaded into the editor (if there is no existing symbol definition, the Symbol Editor will initially be empty). To clear the editor and start with an empty symbol, select Symbol | New. Please note that this new symbol is still attached to the currently selected type.

To save the symbol definition, select Symbol | Save or press the Save button in the toolbar.

To undo Symbol Editor operations, select either Edit | Undo or press the Undo toolbar button (or press Ctrl+Z). To redo, select Edit | Redo or press Redo toolbar button (or press Ctrl+Y).

Normally a symbol definition is simply saved as part of the type it belongs to. However, there is often a need to reuse symbols or parts of symbols between types, and therefore the Symbol Editor allows symbol definitions to be stored in the Symbol Library of the current default project. To save the symbol definition into the Symbol Library, select Symbol | Save to Library... and enter the name for the symbol definition when prompted.

To browse, manage and retrieve symbols in Symbol Library, select Symbol | Browse Library.... This will open the Symbol Library Browser as shown in Figure 3–2. It is worthy to note that Symbol Library Browser allows browsing and retrieving of not only symbols stored into the library but also symbols of other types loaded from the repository. By default the browsed shows the symbols stored in the library. To view the symbol in other types, press Show Types button on top of the screen. This will change the view to similar as in Figure 3–3. To view the symbols in the library again, press Show Library button.

Available symbol definitions are shown in the list on the left and a preview of the selected symbol is displayed on the right. To load the symbol definition from the library or other type, press the Paste & Close button. This will retrieve the symbol elements and place them on the drawing area. Please note that this addition is non-destructive, so the symbol elements possible already existing on the drawing area are spared. To remove the selected symbol definition from the symbol library, press the Delete button and select Yes in the confirmation dialog (please note that you cannot delete symbol definition from another type this way). To exit the Symbol Library Browser, press the Close button or close the browser window.

It is worth noting that property text fields cannot show the names of the properties in the preview (the figure contains only fixed text elements). When pasted, unless into the same symbol or a subtype, you must assign the desired properties to the text fields.

To import a bitmap as a symbol element, select Symbol | Import Bitmap... and select the bitmap file from the file dialog that opens. Supported file types are .bmp, .gif, .jpg and .png. For more information about bitmap symbol elements, see Section 3.2.8.

The Symbol Editor provides a mechanism for exporting symbol elements as Scalable Vector Graphics (SVG) documents and importing these documents back to MetaEdit+. SVG is an XML notation for describing vector graphic images. MetaEdit+ supports the SVG Tiny 1.2 profile – for more information about this format, please refer to www.w3.org/TR/SVGMobile12.

To export the current symbol's elements to an SVG file, select Symbol | Export SVG.... Enter the name for the SVG file when prompted. To import elements from an SVG document, select Symbol | Import SVG... and select the SVG file from the file dialog that opens. If errors are encountered during the export or import, a warning dialog will be shown providing information about the possible cause of the error.

To exit Symbol Editor, select Symbol | Exit or close the Symbol Editor window. If there are unsaved changes, a dialog as in Figure 3–4 will be shown to prompt whether or not to save them.

Using the grid helps you position and scale symbol elements accurately. When the grid is active, elements are not moved or scaled completely freely anymore, but with defined steps. To set the grid step, select View | Choose Grid... to open the grid size dialog (Figure 3–5). In the grid size dialog you can set the grid step values for both axes either by entering them into their respective number fields or by using the sliders. If you want to make sure that the grid for both axes is the same, check the Uniform grid check box. Pressing the Default button will restore the default grid step values.

To make the grid visible in the drawing area, select View | Show Grid or toggle it on by checking the Show checkbox in the Grid section of the status bar on the bottom of the window. To activate the grid, choose View | Snap to Grid or check the respective checkbox in the status bar. Once activated, all further element operations will conform to the grid steps. However, activating the grid does not force symbol elements to align themselves along it. To do this, select Align | Align to Grid: this will align the top left of the selected elements (or all elements if none are selected) to the nearest grid point.

The Symbol Editor is opened with a 200% zoom by default. To change the zoom, either:

Or:

Or one of the following:

To refresh the drawing area, either select View | Refresh from the menu or press F5.