Development of Linear Measure Tool using Application Framework

1
Development of Linear Measure Tool using
Application Framework

• Venkatesh Merwade

2
Overview

• Necessity for Linear Referencing
• Application Framework
• About Linear Measure Tool
• PolylineM
• LengthDown
• Application of LMT
• Conclusions, Acknowledgements, Questions!

3
Necessity for Linear Referencing

• GIS often represents spatial information with two
  dimensional coordinate systems.
• Location of river gauging station
• x,y coordinates - (992506,301256)
• Linear measure - HydroCode 30021, m165
• Add route events
• Find distance between two points and so on.

4
Application Framework What is it??

• Its an ArcMap extenstion
• Designed to access ArcMap layers for input and
  create new output layers (right now used only for
  input).

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Why AppFramework?

• Here is how it all works
• Get hold of MxDocument
• Get hold of Map
• Get hold of FeatureLayer
• Get hold of FeatureClass
• Get hold of required Field in FeatureClass
• Do Something, have fun!
• Display results

AppFramework
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Sub LengthDown() Dim pMxDoc As
IMxDocument Dim pMap As IMap Set pMxDoc
ThisDocument Set pMap pMxDoc.FocusMap
Dim pFLayer As IFeatureLayer Dim pFeature As
IFeature Set pFLayer pMap.Layer(0) Dim
pFC As IFeatureClass Set pFC
pFLayer.FeatureClass Dim pTable As ITable
Set pTable pFC Dim j As Long j
pTable.FindField(LengthDown") If j -1
Then MsgBox Field not found"
Exit Sub End If MsgBox Field Found
End Sub
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Linear Measure Tool (LMT)

• Its developed in Visual Basic as a DLL.
• Uses AppFramework for input.
• Register in ArcMap to use it.
• Toolbar with some cool options for Linear
  Referencing.
• Works only with PolylineM layer and uses
  LengthDown for multiple features option.

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Why LMT is so cool!

• It has some cool options!
• Assign Ms
• Read Ms
• Finds out distance between two points
• Deals with both Individual and Multiple Features
• Changes the MDomain on fly if necessary
• It flashes but never crashes (sometimes gives
  error message, but thats not LMT, its user!)

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Application of LMT
10
Conclusions

• Using Visual Basic, I can do some cool stuff too.
  Its very easy.
• Here we are dealing with only one type of Layer
  (PolylineM). AppFramework is more useful when
  dealing with different types of layers and
  fields.

11
Acknowledgements

• Dr. Maidment
• Tim Whiteaker
• CRWR crew