07 Filters

Filters are used in DELFT-FEWS to define the locations that are displayed on the main map display, and that can be selected to display data. Filters are defined to arrange locations, with associated parameters in logical groups. Each filter is defined as a collection of time series sets.

Filters may be defined as a nested structure, allowing for the definition of a hierarchal set of filters.

When available on the file system, the name of the XML file is for example:

Filters 1.00 default.xml

Filters                                       Fixed file name for the Filters configuration

1.00                                            Version number

default                                       Flag to indicate the version is the default configuration (otherwise omitted).

Figure 31 Elements of the filters configuration

description

Optional description of the filter configuration. Used for reference purposes only.

filter

Definition of a filter. Multiple entries may exist where multiple filters are defined. Each filter may contain either a set of one or more time series set, or a child filter. The child is a reference to another filter definition that again contains either a child filter or a list of time series sets. This structure is used to construct a hierarchal tree view of filters.

Attributes;

• id: Id of the filter. This ID is used in the tree view in the main display
• name: optional name for the filter. For reference purposes only.
• ValidationIcons: This allows the user to make use of the addtional validation icons available in the explorer (2009.01)

timeSeriesSet

Definition of a time series set belonging to a filter. Multiple time series sets may be defined.

child

Reference to another filter. The child element refers to the ID of the other filter as a foreign key.

Attributes;

• foreignKey: Reference to ID of another filter

Example (time series sets not expanded) 
	<filter id="Config Example">
		<child foreignKey="Nested Filter"/>
	</filter>
	<filter id="Nested Filter">
		<timeSeriesSet/>
	</filter>
	<filter id="Main Level Filter">
		<timeSeriesSet/>
	</filter>

Figure32 Example of filter configuration, as defined in the example XML configuration above.