Selecting elements

If you click on the checkbox "selected" the navigation buttons will work only for features that are previous selected. If a feature is selected, the bottom area of the NavTable Window will be highlighted in yellow. In between parentheses the number of selected records can be seen next to the whole number of records.

In this image you see an example explaining how this function works: record 8 for a layer with 20 records is displayed where 7 records are selected.

If the checkbox "selected" is activated without any selected feature, all records will be shown empty and the box will not display any number. and .

The option "select" is another interesting tool you can find next to "selected" in the Nav Table menu. If you activate the checkbox next to "select", the attributes you are visualizing will be selected and highlighted in the view. In the case that other features were selected, this option will turn them unselected and will select only the register you are visualizing.

On top of the NavTable Window there is the button "Filter" . If you press it, a dialogue window will appear in which you can define exactly what you want to select (attributes and calculations). If you click on "clear selection" all selections will be turned off and no features will be selected.

Zoom to feature

If you click on the zoom button the feature will be displayed in the center of the view, referring to the record you are working with at that time. The scale of the view will be changed to have a good visualization of the data. In case you are working with a point layer, a scale size will be chosen that allows to see also the surroundings of the point.

With help of the button "always zoom" next to the checkbox "select", Navtable will zoom to each feature referring to the record you are visualizing. If you click on "fixed scale" as well, Navtable will zoom to the feature and display it in the center of the view, but the scale will always remain the same. It is possible to change the scale value introducing a new one in the "scale bar" of gvSIG. This is shown on the buttom right of the gvSIG view, next to where the coordinates are displayed.

Tip: The options "always zoom" or "fixed scale" together with "select" is a very interesting way of navigate through the features of a layer.

Quick filters

Navtable offers you a comfortable way to make quick filters. If you want to use this functionality you must select a row in Navtable which has one of this attribute types: number, string or boolean. If you click on the right button of your mouse a new menu will be displayed which shows you the different options to define filters.

If the selected field is of type "string" one of the following options will be shown:

• is the same than [current text]
• is different than [current text]
• contains... (a new dialogue window will be displayed introducing text that Navtable should find between all other records)
• Filter (this option will call the "Filter" function of gvSIG as we have seen it before)
• Clear Selection (if a feature is selected)

If you want to use the quick filter of Navtable on a numeric field you will have these possibilities:

• is the same than (==) [current value]
• is different than (!=) [current value]
• smaller than (<) [current value]
• greater than (<) [current value]
• filter
• clear filter

Regarding boolean fields the filter options are the followings:

• equal to "TRUE"
• equal to "FALSE"
• filter
• clear fliter

If there are selected records the "clear filter" option can be activated to delete the current selection. Each time you use Navtable´s quick filter option a new selection will be made and the actual one will be cleared.

Notice: You should consider that NavTable will show you an empty record if you use a filter and you have to activate the checkbox "selected". Every feature has the condition you are looking for including the expression you have defined for the filter.

Warning: if there is a great amount of records inside the table, the processing of the Navtable filter operations could take a long time (like in gvSIG filter itself). Please consider that there is a known bug in gvSIG when using filters with decimals in numerical fields and the "equal to" operator.

Filter for date fields have not yet been implemented in Navtable.