The Vector Properties Dialog:Attributes Tab
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Attributes Tab
Within the Attributes tab the attributes of the selected dataset can be manipulated. The buttons New Column and Delete Column can be used, when the dataset is in editing mode. At the moment only columns from PostGIS layers can be edited, because this feature is not yet supported by the OGR library.
The Toggle editing mode button toggles this mode. <P> edit widget <P> Within the Attributes tab you also find an edit widget and a value column. These two columns can be used to define values or a range of values that are allowed to be added to the specific attribute table columns. They are used to produce different edit widgets in the attribute dialog. These widgets are: <P>
- line edit: an edit field which allows to enter simple text (or restrict to numbers for numeric attributes).
- unique value: a list of unique attribute values of all pre-existing features is produced and presented in a combo box for selection.
- unique value (editable): a combination of `line edit' and `unique value'. The edit field completes entered values to the unique value, but also allows to enter new values.
- value map: a combobox to select from a set of values specified in the
value column the Attributes tab. The possible values are
delimited by a semicolon (e.g.
high;medium;low
). It is also possible to prepend a label to each value, which is delimited with an equal sign (e.g.high=1;medium=2;low=3
). The label is shown in the combobox instead of the value. - classification: if a unique value renderer is selected for the layer, the values used for the classes are presented for selection in a combobox.
- range (editable): A edit field that allows to restrict numeric values to a
given range. That range is specified by entering minium and maximum value
delimited by a semicolon (e.g.
0;360
) in the value column of the Attributes tab. - range (slider): A slider widget is presented that allows selection of a value
in a given range and precision. The range is specifed by minimum, maximum
value and a step width (e.g.
0;360;10
) in the value column of the Attributes tab. - file name: the line edit widget is accompanied by a push button. When pressed it allows to select a filename using the standard file dialog.