Working with Attribute Schemas – Avenza Maps

This tutorial will explore how to create an attribute schema, the 4 different types of attributes, how to import and export a schema, and how to edit a schema.

Creating an Attribute Schema

1. Open Toronto, ON Parks & Trails (West)

2. Tap the Map Features button in the toolbar to access the Map Layers page

3. Tap Add Layer and name the new layer “Gas Stations” then tap OK

4. Tap Edit, ensure the layer is selected and tap the pencil icon to enter the Edit Layer page

5. Make the new layer the current layer by toggling the switch on

6. Set the Default Placemark Name to “Gas Station”

7. Under Attribute Schema add the following new attributes using the Add button:

8. Add an attribute for the name of the gas station

1. 1. Attribute name: Name
  2. Type: String
    - Allows alpha-numeric and special characters

9. Add an attribute to show whether or not the gas station offers diesel

1. 1. Attribute name: Diesel
  2. Type: Boolean
    - Yes/No or True/False

10. Add an attribute for the current price of gas at the gas station

1. 1. Attribute name: Price
  2. Type: Real
    - Allows any numerical value including decimals

11. Add an attribute for how many pumps the gas station has

1. 1. Attribute name: Pumps
  2. Type: Integer
    - Allows only whole numerical values (no decimals)

12. Add an attribute for the type of loyalty card the gas stations accepts, if any

1. 1. Attribute name: Loyalty
  2. Type: String
  3. Create a picklist for this attribute with the following values
    - Air Miles
    - PC Optimum
    - None

Exporting an Attribute Schema

1. Open Toronto, ON Parks & Trails (West)

2. Tap the Map Features button in the toolbar to access the Map Layers page

3. Tap Export Layers

4. Change the File Name to “GSschema.kml”

5. Change Format to KML

6. Change Data to Schema Only

7. Tap the Export button and save the file in your preferred location

Importing an Attribute Schema

1. Open Toronto, ON Parks & Trails (West)

2. Tap the Map Features button in the toolbar to access the Map Layers page

3. Tap the Import Layers icon

4. Ensure the “Import Schema Only” box is checked

5. Under Storage Location, tap the option that corresponds with where your KML file was saved

6. A new layer has been created containing the attribute fields you created in the previous steps

7. The duplicated layer can now be deleted by tapping Edit and then selecting Delete

Using an Attribute Schema

1. Open Toronto, ON Parks & Trails (West)

2. Tap the Map Features button in the toolbar to access the Map Layers page

3. Ensure the Gas Stations layer is the active layer

4. Return to the map view

5. Tap the Add Placemark button to create a new placemark

6. Change the name of the Placemark from Gas Station 1 to Shell

7. Before confirming the addition of the feature, scroll down to “Attributes”

8. In the Attributes section, tap the attribute you need to enter data for

9. Enter the following attribute values (if necessary, tap the back arrow to return to the Add Placemark screen from the Edit Attribute Value screen):

1. Name: Shell
2. Diesel: Yes
3. Price: 129.99
4. Pumps: 8
5. Membership: choose Air Miles from the Value list

10. Gas prices can be displayed in different units of measurement so we would like to edit the name of this attribute:

1. Tap the Layer icon above the Attribute list to return to the Edit Layer screen
2. Scroll down to the Attribute Schema and tap the Price attribute to edit it
3. Change the name of the attribute to “Price (cents/liter)”
4. Tap the back button twice to save the change and return to the Add Placemark screen. Notice that the value of “129.99” remains intact.
5. Repeat steps a and b
6. Change the Attribute Type to Integer
7. Tap the back button twice to save the change and return to the Add Placemark screen. Notice that the value of the attribute has been erased due to the type change.
8. Change the Attribute Type back to Real and re-enter 129.99 as its value in the placemark.

11. Tap the checkmark to confirm the placemark addition