arcobject training

ArcObjects Training

Topics

Introduction to ArcGIS Introduction to ArcObjects Object Model diagrams (OMD) Navigating OMD Common ArcMAP Objects Programming with VBA Programming with .net Brief Introduction on SDE

Introduction to ArcGIS


Introduction to ArcGIS– ArcGIS is a suite consisting of a group of geographic

information system (GIS) software products produced by ESRI– software products that consists of Desktop GIS,Server GIS and

Mobile GIS


Desktop GIS consists of ArcGIS Desktop, ArcGIS Engine Server GIS products include ArcGIS Server Mobile GIS products include ArcGIS Mobile and ArcPad


ArcGIS clients

Application/Data servers

ArcGIS DesktopEXTENSIONS

ArcGIS Engine

Components ArcObjects

ArcReader ArcView

ArcInfo

ArcEditor

Customapplication

RDBMS

ArcSDE

ArcGIS Server ArcIMS

EXTENSIONS

ArcPad

Network

Webbrowser


Desktop GIS– ArcGIS Desktop : provides data and tools to help you create,

edit, import, map, query, analyze, and publish geographic information.

– ArcGIS Engine : provides a standard framework for developers to create custom GIS and mapping applications. ArcGIS Engine is a core set of cross-platform components compatible with multiple programming languages that enables developers to rapidly build GIS solutions on ESRI’s ArcGIS platform.


ArcGIS Desktop– ArcGIS Desktop includes a suite of applications including

ArcCatalog, ArcMAP, ArcGlobe, ArcToolbox.– Based on the functionality desktop application available in

three levels of licenses.– ArcView focuses on comprehensive data use ,mapping , and

analysis.– ArcEditor adds advanced geographic editing and data creation.– ArcInfo is a complete, professional GIS desktop containing

comprehensive GIS functionality, including rich geo-processing tools.


ArcMap Main menu Standard toolbar Editor toolbar TOC Tools Graphic Area Status bar Draw Toolbar Data View Layout View Supports Shape files,

PGDB, File GDB, SDE, and data servers.


Practical workouts– How to add files in ArcMAP and Start editing, Modify /Add

features, and Stop editing operations.– Use of MXD files.– Describe Properties of Feature classes.– Toolbars in ArcGIS.– Symbology, Labeling features, and Snap settings.– Querying of data.– Use of ArcCatalog.– Use of ArctoolBox.

Introduction to ArcObjects

Introduction to ArcObjects

What Are “ArcObjects” ?– A set of components/objects of the ArcGIS platform which can

be accessed through programming environment ( VBA, VB, C++,.NET, VB Script)

ArcObjects have– Characteristics which can be queried or set– The ability to perform operations– The ability to respond to changes in application

Object Model Diagrams (OMD)

Object Model Diagrams

OMDs help you write code– Show interfaces, methods, and properties for each class– Show relationships between classes

Over 2,700 classes on several diagrams Over 3,000 interfaces


Synoptic view of ArcObjects Included with ArcObjects Developer Kit ArcGIS installation option Diagrams (OMD’s) in PDF format Located at ArcGIS\DeveloperKit\Diagrams


Reading ArcObjects OMD’s Classes

In ArcObjects you will encounter three distinct types of classes– Abstract Classes– Class (Instantiable Classes)– Co-Classes (Creatable Classes)


Abstract Class – In ArcObjects OMDs these classes

are represented by a 2D shaded rectangle with the class name in italics

– These classes are not creatable or Instantiable.


Class (Instantiable Classes) – In ArcObjects OMDs these

symbols are represented as 3D rectangles with no shading

– These classes are non-creatable classes in the sense that you can’t use the “New” keyword to create a new object instance of these types of classes

– We must use other objects to derive an instance of this type of class


CoClass (Creatable Class)– In ArcObjects OMDs these symbols

are represented as a shaded 3D rectangle.

– These classes can be created with “New” keyword to create a new object instance of these types of classes.

– In addition, object instances from these classes can be created from other objects just as they can with Instantiable objects


Interfaces– In ArcObjects OMDs

Interfaces are represented with a “Lollipop” symbol

– Interfaces are like sub-classes within a larger class

– Interfaces expose various characteristics and behaviors of a class through properties and methods


Relationship Notation– Is a type of– Is composed of– Creates a– Multiplicity– Association

*_____

Egg

Bird

Wing

Feather

2

Abstract

Class

Class

Class

ChickenCoClass

NestCoClass

*


Methods and Properties

– Properties are represented by the “Barbell symbol”

– Read/Write property

– Read Only property

– Write Only property

– Property Put by Reference

– Methods are represented by an arrow

Navigating OMD

Navigating OMD

Example: Return name of first layer in ArcMap TOC– Start with IMxDocument,

interface of document object, MxDocument

– Use FocusMap property to reference the Map object through IMap interface

Navigating OMD

Example: Return name of first layer in ArcMAP TOC– Start with IMxDocument, interface

of document object, MxDocument– Use FocusMap property to

reference the Map object through IMap interface

– Use Layer property of the map to reference layer object

Common ArcMAP Objects

Common ArcMap Objects

Common ArcMap Objects

MxDocument

Map

Layer

*

*

FeatureLayer

Application

Programming With VBA


Scope– Using VBA, you author macros that are stored within the

document/template structure of the application– You can also create custom commands and tools, called UI

Controls.– UI Controls are macros that also contain hooks into the application

framework so that you can respond to actions that happen on the buttons or commands you create.


How to access the VBA environment in ArcGIS – VBA programming is accessible through the Tools->Macros->Visual

Basic Editor


Document Events– Code executes when user interacts with document– Open document– Close document– New document– others


Defining Variables– Must define object variables before setting

– Use the Dim, Private, or Public statements

– Variables pointing to ArcObjects must reference one of the object’s interfaces


Defining procedure scope– Public: May call procedure from any module

– Private: Procedure may be called only from other procedures in the same module


Most generally used ArcObjects libraries

FeatureLayer

Map

MxDocument

Carto*

*Layer

FeatureDataset*

Geodatabase

FeatureClass

Table

DataSet

0 .. 1Carto Layer


Access maps from MxDocument– Get the active map

– Get all maps (IMaps)

Dim pMxDoc As IMxDocumentSet pMxDoc = ThisDocumentDim pMap As IMapSet pMap = pMxDoc.FocusMap

Dim pAllMaps As IMapsSet pAllMaps = pMxDoc.Maps


Looping through a collection of maps

' Map collection example … Dim intIndex As Integer Dim pMaps As IMaps Set pMaps = pMxDoc.Maps

For intIndex = 0 To pMaps.Count - 1 MsgBox pMaps.Item(intIndex).Name Next intIndex

0

1

2


Access layers from Map or MxDocument– Get the selected layer (IMxDocument)

– Get a specific layer (IMap)

– Get all layers (An enumeration of layers)

Dim pLayer As ILayerSet pLayer = pMxDoc.SelectedLayer

Dim pLayer As ILayerSet pMap = pMxDoc.FocusMapSet pLayer = pMap.Layer(3)

Dim pAllLayers As IEnumLayerSet pAllLayers = pMap.Layers


IMap’s Layers property returns IEnumLayers– Like a collection with fewer methods and properties– Next returns ILayer– Reset moves to top of Enum

Set pLayer = pLayers.Next

Nothing

pLayers.Reset

IEnumLayerTop




Dim pLayer As ILayerDim pLayers As IEnumLayerSet pLayers = pMap.Layers


Looping through layers– Loop based on a Condition

' Layer enum example Dim pLayer As ILayer Dim pMapLayers As IEnumLayer Set pMapLayers = pMap.Layers

Set pLayer = pMapLayers.Next Do Until pLayer Is Nothing MsgBox pLayer.Name Set pLayer = pMapLayers.Next Loop

Nothing!


Data creation objects

Table

FieldsField 1 ..

DatasetWorkspaceWorkspaceFactory

AccessWorkspaceFactory

Row

FeatureClassArcInfoWorkspaceFactory

ShapefileWorkspaceFactory

Others

*

WorkspaceFactory


Opening an existing Workspace– Use IWorkspaceFactory to return a Workspace object– Generic interface for all sub-types of WorkspaceFactory– OpenFromFile: Access an existing folder on disk– Open: Connect to an existing database (e.g., ArcSDE)


Connecting to an ArcSDE database– Use SDEWorkspaceFactory

– Set connection properties with IPropertySet

Use IWorkspaceFactory toretrieve a workspace

Use SetProperties methodto set Database Connection properties (Server, Instance, etc)


Getting a FeatureDataset– IFeatureWorkspace interface on Workspace– OpenFeatureDataset method

Dim pFWorkspace As IFeatureWorkspaceSet pFWorkspace = pWorkspace 'QI for IFeatureWorkspace

Dim pCover As IFeatureDatasetSet pCover = pFWorkspace.OpenFeatureDataset("streets")

FeatureClasses

Workspace FeatureDataset


Getting FeatureClasses– Use IFeatureClassContainer to get existing FeatureClasses from a FeatureDataset


Adding a shapefile to mapPublic Sub Addshapefile()

Dim pWorkspaceFactory As IWorkspaceFactoryDim pFeatureWorkspace As IFeatureWorkspaceDim pFeatureLayer As IFeatureLayerDim pMxDocument As IMxDocumentDim pMap As IMap 'Create a new ShapefileWorkspaceFactory object and open a shapefile folder

Set pWorkspaceFactory = New ShapefileWorkspaceFactorySet pFeatureWorkspace = pWorkspaceFactory.OpenFromFile("D:\Program Files\ArcGIS\DeveloperKit\SamplesNET\data\World",

0) 'Create a new FeatureLayer and assign a shapefile to it

Set pFeatureLayer = New FeatureLayerSet pFeatureLayer.FeatureClass = pFeatureWorkspace.OpenFeatureClass("Country") pFeatureLayer.Name = pFeatureLayer.FeatureClass.AliasName 'Add the FeatureLayer to the focus mapSet pMxDocument = Application.DocumentSet pMap = pMxDocument.FocusMap pMap.AddLayer pFeatureLayer

End Sub


GxDialog• ArcCatalog type dialog box for browsing directories

– User-friendly identification of input/output files– Can open modally for saving or opening a file

• Properties that define appearance and behavior– StartingLocation– Title– ObjectFilter– AllowMultiSelect– FinalLocation


Example: GxDialogDim pGxDialog As IGxDialogDim pGxObjEnum As IEnumGxObjectSet pGxDialog = New GxDialog

pGxDialog.AllowMultiSelect = TruepGxDialog.StartingLocation = "D:\Program Files\ArcGIS\DeveloperKit\SamplesNET\

data\World"pGxDialog.Title = "Select Files for Input"pGxDialog.ButtonCaption = "GO!"pGxDialog.DoModalOpen 0, pGxObjEnum


Looping through layers

Geometry objects

Point MultiPoint

Ring

PathSegment

Geometry

EnvelopeCurve

Polyline

Line BezierCurveCircularArc

Polycurve

**

*

Polygon

*

Geometrycollection

*

Segments have start and endwith curve in between

Aggregate to paths/rings Aggregate to lines/polygons Edit at any level

Feature geometry

Points

Segments

Bezier curve

Line Circular arc

3 Rings (closed paths)

2 Paths

1 Poly1 Line

Multipoints PolygonsPolylines

Points and multipoints

Points are zero dimensional– Defined with x- and y-coordinates– May have Z and M properties

Multipoints are collections of points

Point

Multipoint with six points

Dim pPoint As IPoint

Set pPoint = New Point

pPoint.X = 300

pPoint.Y = 450

Dim pMultiPts As IPointCollection

Set pMultiPts = New MultiPoint

pMultiPts.AddPoint pPoint

Consist of two points (From and To) and a function defining the curve between them

Subclasses: Line, BezierCurve, CircularArc Segments used to create other geometry

– Paths, polylines, rings, and polygonsDim pLine As ILineSet pLine = New LinepSegment.FromPoint = pPointApSegment.ToPoint = pPointB

Segments

From

To

FromTo

Polylines and polygons

Polylines– Collections of connected or unconnected paths

Polygons– Composed of one or several rings

1 Polyline with four segments

1 Polygon with seven rings

Envelopes

Define a feature’s spatial extent– Minimum bounding rectangle

All geometry has an envelope– Get or set with IGeometry :: Envelope

Dim pEnvelope As IEnvelopeSet pEnvelope = pLine.Envelope

Zooming in to a Feature

Get the extent using a shape’s Envelope property– On the IGeometry interface– Set the ActiveView Extent property with an Envelope

Feature Geometry

Envelope1 Polygon Feature

pMxDoc.ActiveView.Extent = pFeature.Shape.EnvelopepMxDoc.ActiveView.Refresh

Geometry spatial operator interfaces

Interfaces supported by subtypes of Geometry– ITopologicalOperator– IProximityOperator– IRelationalOperator

Use to …– Perform familiar spatial operations such as buffer, cut, and clip– Measure distances between shapes– Examine spatial relationships

ITopologicalOperator

Provides methods for working with geometry Supported by Point, Multipoint, Polyline, and Polygon

BufferIntersect Union

Cut Clip

Dim pTopoOp As ITopologicalOperator

Dim pBuffPoly As IPolygon

Set pTopoOp = pFeature.Shape

Set pBuffPoly = pTopoOp.Buffer (intBufferDistance)

IRelationalOperator

Methods for examining spatial relationships (return Boolean)– Equals: Are input geometries structurally equivalent?– Touches: Do input geometry boundaries intersect?– Contains: Is one geometry contained by the other?– Disjoint: Are input geometries spatially distinct?– Several others

Dim pRelationOp As IRelationalOperator

Dim booTouches As Boolean

Set pRelationOp = pPoly

booTouches = pRelationOp.Touches (pAnotherPoly)

IProximityOperator

Methods for examining proximity relationships between features– ReturnDistance: Returns the minimum distance between

features (double)– ReturnNearestPoint: Finds and returns the nearest point on the

specified feature (point)

Dim pProxOp As IProximityOperator

Dim dblDistance As Double

Set pProxOp = pLine

dblDistance = pProxOp.ReturnDistance (pSomeOtherLine)

?

Basic steps: Building a COM component

1.Create a new COM project2.Create a COM Class3.Reference the ArcObjects libraries4.Implement the required interface(s)5.Compile the component as a DLL6.Register your component with ArcGIS

The steps are the same regardless of the language

Programming With . Net

Programming with .net

Introduction– In the past, ArcGIS programming was largely written in VBA

(Visual Basic for Applications) Script. This language, while useful for writing macros for applications, lacks the depth and breadth for large scale major initiatives which programming in the .Net framework can provide. To this end, ESRI has made it possible to program in the .Net Framework.


Software Requirements– ArcMap 9.2 (With service pack 6)– ArcGIS .Net SDK (Option available While Installation)– Microsoft Visual Studio dot net 2005


Programming Wizard– Available with ArcGIS

installation– Guide you to create the

classes and toolbars– Generic code (default

Events) will be available with new classes.


Steps to write program– Navigate to File > New > Project…

– In the Project Types bar, expand the Visual C# (or the Visual Basic if you want to use VB) and expand the ArcGIS subfolder. In this Subfolder will be the Desktop folder (Or MapInfo, or Engine if you have that installed). Once this is selected you will see a number of options in the Templates box, Select Class Library (ArcMAP).

– Click OK!


Steps to write program– Right click on Class1.cs in the Solution Explorer and select

Delete.

– In the Solution Explorer, right click on the HelloArcGIS that is in bold typeface.

– Select Add > New Item.

– At the Add New Item Dialog Select Base Command. Leave the Name textbox as the default/Give specific name and click Add.

– Select Desktop ArcMAP Command, Click OK.


Steps to write program– Edit each of the public properties of your command so that they

reflect the command you are creating.

– Expand the Overridden Class Methods code region

– Click on Project > Add Reference

– Scroll down and select the System.Windows.Forms DLL.

– Click OK


Steps to write program– Modify the using statements as per requirement.

– Modify the OnClick method so that the code to display a message box is included

– Double click on Command1.bmp in the Solution Explorer to open up the bmp editor in MSVS, edit the bmp in any way you would like using the tools included in MSVS

– Click on Build > Build Solution


Steps to write program– Click on Debug > Start Debugging

– Right click on a menu bar in ArcMap and select the Customize… button

– Select the Commands tab, and then locate ArcGuides in the Categories list. Select

– “Hello World For ArcGIS” and click and drag it onto an ArcMap toolbar


Practical workouts– Hello world ICommand

– Read layers and Feature classes

– ITool with draw features on map

– Toolbar example

– Different types of feature selection methods

– Query filter and Spatial filter

– Use of Topological operators

– Read/Write feature attributes

– Apply symbols

Help Documents

Sample source code & Help Documents– http://arcgisdeveloperonline.esri.com

http://arcgisdeveloperonline.esri.com/

Questions

Thank You