tab: uscty_20.tab


Filename - obEdDlph.zip

This Delphi 4.0 example uses the MapX Ver 4.0 OCX Control.  The main goal of this example is 
to show the use of the new object editing capabilities in MapX Ver 3.51.  The program show how
 to perform functions such as adding a new layer (temporary or permanent), adding lines and
 points, and editing a layers data.

Files:

FeatureInfo.dfm
FeatureInfo.pas
MainMap.dfm
MainMap.pas
NewLayerDialog.dfm
NewLayerDialog.pas
ObjectEditing.dpr
ObjectEditing.res

Overview:

There are 5 Menu Item choices, the Map Control and a combo box that holds a list of layers.  Under the File menu option is the "exit" option to end the program.  

Layers menu option: The first is "Layer Control" which displays the Layer Control Stock 
MapX Dialog.  The second is "Add New Layer" which displays a modal form with two edit 
box controls.  The first edit control is for the new layers name and the other is for 
the path to save the new table that will be created.  If the "Temporary" Checkbox is 
checked, the Path information is ignored.

Tools Menu option: The first four zoomIn, zoomOut, pan and select all set the active tool
 to be the respective MapX default tool.   The Fifth, "Info", displays a dialog with 
information about the currently selected feature from the layer listed in the combo box 
at the bottom of the form.  To perform a selection, choose the selection tool.  The sixth 
choice has a sub-menu for drawing tools.  The only options highlighted here are for Point
 and Line. 1The two choices that are disabled are for drawing polylines and polygons.  
The line and point tools allow you to add objects to the layer that is specified in the
 combo box at the bottom of the form.

Styles: The Styles menu has three choices, symbol style, line style and region style. 
These choices bring up the stock MapX style dialogs.

Objects: There are three choices under this.  The 1st deletes the first selected feature
 in the edit layer.  The 2nd Buffers the selected items in the feature layer (feature 
layer combo) and the 3rd combines the first and second selected items in the feature 
layer.


1 There appears to be a limitation of Delphi 2.0 and the OCX. In Delphi, a double click 
on the control does not send and event to the OCX and thus the PolyToolUsedEvent does not
 get called for a double click.  Because of this, the Enter key or the spaceBar must be
 used as double click replacements.