Modify Layer

When you select the Modify command you are asked to select a layer to modify and then the layer properties dialog is shown. This is the same dialog as you get when you click the Properties link for a layer on the Key. Please note that there is an important difference between the two. When you select the Modify button you are changing the default settings for the layer, when you select Properties from the Key you are changing settings that belong to that map only. What happens is that when you add a layer to the map the corresponding settings are copied to the map. This allows you to change them without affecting other maps. On the General tab you can set a title and a description. The title is that shown on the Key. You can also determine its visibility. You can use the combo boxes shown to set the visibility to switch on or off at certain scales. For example you might want to switch Cartographic Text off above a certain scale as it will no longer be readable. The Selectable checkbox is used to determine whether the layer will be affected by the operations on Earthlight’s Select tab.

How to use Modify tool

To open a layer in Modify mode, please click on the tool icon and pick a layer from the repository.

Clicking OK button will open the layer properties.

At first blush it looks like ordinary Vector Layer Properties window but after closer look you will notice that there are some differences in Schema tab opened by Modify tool.

Layer properties Schema tab opened by Modify tool.

There are 2 additional buttons:

1. Add
   This button allows you to add a new column to existing table .Earthlight requires around 10 seconds to communicate with database and to create the new column.
   
   The Add New Column window allows you to enter the new column name and to choose the column type. You can select one from the following types:

   • Integer

   • Real

   • Text

   • Date

   Please click the OK button to proceed with the operation. 

   Important:

   Please remember that the column name must be correct from the database point of view (cannot contain any illegal characters).

2. Delete This button allows you to delete an existing column. Please select a column and click the Delete button to proceed with the operation. A Delete Column window will appear.
   
   If you are sure that you’ve selected the correct column please confirm the deletion by clicking Yes button, or No to cancel the operation.