Change transparency (Map Viewer Classic)

Note:

A new Map Viewer is now available. The new Map Viewer was previously available as a separate beta installation but is now available in the portal automatically. Open it from the app launcher to get started. To learn more, see the new Map Viewer help documentation.

Changing the transparency, or opacity, of a layer in a map allows you to see more, or less, of the underlying layers. The transparency of any layer can be adjusted from 0 percent to 100 percent. The more transparent a layer is, the less visible it appears on the map and the more visible the other layers appear. By default, the basemap is 0 percent transparent (which means it is fully visible, or opaque). If you want to focus attention on the data layers in your map, you might consider making your basemap more transparent. Similarly, you could highlight a specific layer by making it fully visible and adding transparency to the other layers. You can change the transparency of layers. You can also change the transparency of sublayers in CSV files, shapefiles, GPX files, and map notes.

Change transparency through the Change Style pane

  1. Open the map in Map Viewer Classic.
  2. Click Details and click Contents.
  3. Browse to the layer whose transparency you want to adjust, click Change Style Change Style, and click Options on the thumbnail of the layer.

    A transparency slider appears at the bottom of the pane.

  4. To set the overall transparency of the layer, move the slider to the left (less transparent) or right (more transparent). You can also click on the slider track to jump the slider handle to that location.
  5. You can also set the transparency per feature if you have numeric or date data associated with your locations. Setting the transparency based on attribute values allows you to vary how much transparency is applied to each location based on some numeric attribute. For example, if your layer contains income data, you could adjust the transparency of each location proportional to its income.
    1. Click Attribute Values, click the Field drop-down menu, and select the numeric or date attribute to use as the basis for the transparency.

      You can also create a custom expression written in the Arcade scripting language when setting transparency for features. If the layer has an existing expression, you can select it from the bottom of the drop-down menu. Optionally, you can edit the expression directly in Map Viewer Classic by clicking the Edit Expression button and making changes in the editor window.

      In addition, you can create your own expression by selecting New Expression from the drop-down menu and using the editor window to create your expression, including giving it a name. Arcade expressions are supported for all styles except Heat map, Predominant Category, Predominant Category and Size, and Age styles. You can use existing expressions to build new expressions, but be aware that certain variables may not work across profiles. To use an existing expression, select it from the Existing tab in the editor window.

    2. Optionally select an attribute from the Divided By drop-down menu to use to standardize or normalize your data, such as dividing population by area or costs by total population.
    3. Adjust the position of the handles to change how the transparency gradient is applied. You can also click the numeric values beside the slider handles and type in precise values. If the handles are close together, you can use Zoom in to help you see more detail over a small portion of the ramp.
    4. Under Transparency Range, adjust the percent of transparency for the high and low ends of the ramp above. Note that 0 percent transparency is a solid color (fully opaque).
    5. For Type (Unique Symbols) only, click the color chip beside the category name to adjust the transparency applied to any individual category.
    6. Click OK to apply your changes.
  6. If you own the map, click Save to save the transparency setting to the map.

Change transparency through the layer menu

Note:

You can change the transparency through the layer menu for all types of layers including feature layers and basemaps.

  1. Open the map in Map Viewer Classic.
  2. Click Details and click Contents.
  3. Browse to the layer whose transparency you want to adjust, click More Options More Options, click Transparency, and move the transparency slider to the left (less transparent) or right (more transparent).
  4. If you own the map, click Save to save the transparency setting to the map.