Creating and Editing Layers
Before we start creating and/or editing layers, you first need to understand the differences between a Visio diagram page and a Visio layer. A background page is used to apply the same backdrop to many pages. Layers are page specific. In other words, if you want an item to appear on many pages, place that item on a background page and assign that background to as many foreground pages as needed. Background pages can also have layers.
Layers are used to group shapes logically. In the Office Layout drawing, all furniture is assigned the layers dealing with furniture. Layers are also used to add depth to a drawing as well as to "protect" drawing elements from inadvertent changes. To create a layer, you must first select View, Layer Properties from the menu bar. You may also right-click on the drawing page and select View, Layer Properties from the context-sensitive menu. Click the New button to create a new layer.
→ See Chapter 10, "Using Files and Setting Custom Properties," for more on protecting drawings.
There are nine layer properties that you need to understand (Name, #, Visible, Print, Active, Lock, Snap, Glue, and Color):
NameThe Name field shows the name of a layer. Some shapes are assigned automatically to layers. If the required layers do not exist, Visio will create them when the shape is first placed.
# (Number of Shapes)This column shows the number of shapes assigned to a layer. It's a toggle, so clicking on the column label shows the number of shapes. Clicking a second time hides the number.
VisibleVisible means that the layer is visible on the drawing page inside Visio 2002. If you choose to remove the check from this column, the shapes on that layer will not show. Shapes assigned to multiple layers will show if at least one member layer is visible. Hiding a layer does not keep it from printing.
Use the Visible property first to determine whether you should turn the print property off. If the drawing page shows what you want then go to Layer properties and ensure that only the visible layers have the print column checked.
PrintThis check tells Visio 2002 to print the layer. You might want to print only certain layers, so remove the check from any layer you don't want to print.
ActiveActive layers are editable, and more than one layer can be active at the same time. That means you can select shapes on an active layer and edit them. It also means that a newly placed shape will be assigned to all the active layers. A layer must be visible to be active.
LockLocking a layer prevents it from being changed. A layer that is locked can be unlocked by removing the check from this column for the chosen layer.
SnapSnap applies to all shapes on a layer. It enables all shapes regardless of layer to snap to shapes on a snap-enabled layer. The reverse is not true. A shape on a layer with Snap disabled cannot have other shapes snap to it. For example, if layer "red" has Snap turned on and layer "blue" has Snap turned off then shapes from "blue" can snap to "red," but "red" cannot snap to "blue."
GlueGlue behaves the same wayas Snap. It means shapes for any layer can glue themselves to a shape on a glue-enabled layer. Shapes without Glue enabled cannot have other shapes glued to them.
ColorChanging the color of a layer enables you to see which shapes belong to which layer much easier. Layers do not have color by default, although that is easily changed. To change the color of a layer, click in the area where the color would appear, to activate a drop-down menu. If none of the built-in choices suits, you may choose More Colors to select a custom color.
All these options are available in the Layer Properties dialog box, shown in Figure 3.8.
All shapes assigned to multiple layers will show in black regardless of any layer-specific color properties.
Figure 3.8 Manage layers more easily by checking Remove Unreferenced Layers and clicking Apply. This removes all layers that have no shapes on them, and then later if you add a shape that needs a layer you removed in this way, Visio will re-create the layer.
Selecting All Shapes in a Layer
After you've placed shapes on layers, you might want to edit them simultaneously. To do this, use these next few steps:
Select all the shapes from a layer.
Next, go to Edit, Select by Type in the menu bar.
You will now be able to choose drawing elements by Shape type or Layer. You may select multiple layers by holding down the Ctrl key and clicking on the layers you want or by holding down the Shift key while clicking and dragging in the list of layers.
After you have selected all the items you want, click OK and the window disappears with all appropriate shapes selected. See Figure 3.9 for the Select by Type dialog box.
Figure 3.9 Use the Select by Type command if you're unsure which shapes belong together.
Assigning a Shape to a Layer
Using Edit, Layer in the menu bar enables you to assign preexisting shapes to newly created layers. This option enables you to view, assign, or edit the current layer designation for a shape. You can assign a shape to as many layers as you want. See Figure 3.10 for the Layer assignment window.
Figure 3.10 Preserve Group Member Layers enables you to keep separate a shape's individual layer assignment and its group assignment.