Quick Start
This section is designed to give you quick, practical experience using GISDK to develop add-ins and custom applications for Maptitude.
If you are an experienced developer, and have used or built applications in other programming and/or macro languages, this section will give you a good overview of the Caliper Script language, and tell you almost everything you need to know about the mechanics of using GISDK.
If you are not an experienced developer, this section will provide you with some hands-on experience with the tools that are provided in Maptitude, and a good overview of the process of developing, compiling, and running GISDK applications. You may want to spend some extra time studying the code samples to make sure you understand them, and you may even want to look up some of the functions that are used here in the Maptitude Help.
In a series of lessons, this quick start will build a simple but useful add-in that you can adapt to your own needs. You will use sample programs whose source code is included in the gisdk\samples folder within your Maptitude program folder. First, you will load and run these programs as is; later on, you can modify them and experiment on your own.
When developing any software application, it is best to do some planning and designing before starting to do the coding. At a minimum you should specify the basic things you want your user to be able to do, and sketch on paper the way the user interface should look. The more detail you include in your "spec" the easier it will be to write the program. It will have fewer errors and require less revision. So, let's write the spec first, and then begin programming.
You want to create a "find and zoom" type of add-in. It will allow the user to click on the map, see a list of point locations within a specified search distance, choose one of them, and zoom the map to show the chosen point and the original clicked point. Your detailed specification looks like this:
- Assume that a map is already open and that it contains a layer of point locations. You will use the populated places layer called Places in the map LESSONS.MAP in the C:\Users\[Username]\Documents\Caliper\Maptitude YYYY\CodeSamples, where YYYY is the year of your Maptitude version and [Username] corresponds to the name assigned to the current user’s account
- The user chooses a command from a new item on the menu bar that opens a Find and Zoom toolbox. The toolbox contains a Click on Map tool
and an edit box for typing a search distance. - The user sets an appropriate search distance, chooses the Click on Map tool , and clicks somewhere on the map.
- If no points are within the search distance then display a message and return, otherwise display a dialog box with a scroll list containing the points within the search distance, plus OK and Cancel buttons. Show the distance, city, and state in the scroll list, with the cities ordered by distance.
- If the user clicks Cancel then close the dialog box. Once the user has chosen a place enable the OK button. When the user clicks OK zoom the map to include the clicked point and the chosen place, then close the dialog box.
- Set up the add-in as a custom application so that, when the user runs Maptitude from a new program icon on the desktop, the add-in is automatically run and its menu is added to the menu bar.
With your spec in hand, you are ready to set up the work environment and get started.
To Prepare for Writing an Add-In
- If you haven’t already done so, start Maptitude and start your text editor.
- Make Maptitude the current application.
- If you have not already done so, start GISDK by choosing Tools>GIS Developer's Kit.
- Open the Maptitude Help file so that you can look up the full documentation of the GISDK functions you will be using. It is very helpful to keep the Maptitude Help window open when reading and writing GISDK code. When you know the name of the function you are looking for, click the Index tab and type in the first few characters of the function, then click the appropriate item in the list. If you are trying to decide which function to use, click the Contents tab and choose the Outline of Topics page in the Help for GISDK book.
For more information, see:
Lesson 1: A Search Macro and a Test Program
Lesson 4: Calling the Toolbox from the Menus