Stroke symbol layers are components of symbols
Draws linear geometry with a single solid color and width
Draws linear geometry with an image file
Stroke symbol layers can also be used in mesh symbols to draw the edges of multipatch features and 3D object scene layers. In this context, stroke symbol layers can only be of type Solid stroke, and you can not set any property other than color.
Use the pull-down menu within each layer as they are listed in the Format Symbol mode of the Symbology pane, on the Properties tab, on the Layers tab to set the layer type.
Solid stroke symbol layers
Solid stroke symbols contain two main properties, Color, which can be partially transparent, and Width.
Picture stroke symbol layers
Picture stroke symbol layers use an image file to draw linear geometry. In the Format Symbol mode of the Symbology pane, on the Properties tab, on the Layers tab, expand the Appearance group. Click Picture to browse to an image file. Valid file formats are *.bmp, *.jpg, *.png, or *.gif. Adjust the Quality, Tint, and Size properties as necessary.
Set the Tint property to white, which is the default setting, to draw the image in its native colors. Setting this property to no color causes no image to be drawn at all.
Click Reset size to revert the image to its native size.
Stroke symbol layer properties
Both types of stroke symbol have additional properties that define the appearance of the symbol in which they are contained.
The graphical stroke can be drawn perpendicularly offset relative to the geometry. Define the offset distance from the Offset property in the Offset effect group. Choose a Join style—Bevel, Round, or Miter—to control how the joins are handled at the offsets.
Offsets in a stroke symbol layer are actually symbol effects with a default definition of no offset. This is a convenience to easily adjust a stroke offset without having to add an effect. This effect can be managed just like any symbol effect in a symbol layer. When symbols with offset stroke layers draw, the offsetting is processed prior to any dashes present on the stroke.
Like stroke offsets, stroke dashing is also handled with an already available Dash effect with a default definition of no dash (a solid, uninterrupted stroke.) This effect is added as a convenience to stroke symbol layers and can be managed like any other symbol effect.
Choose a dash from the Dash type pull-down gallery and adjust the Dash template values as necessary.
Caps and joins on strokes
The properties in the Cap & Join group define how the stroke should draw at the ends and junctures.