IBM Visualization Data Explorer Programmer's Reference

17.2 Example 1: sealevel.c

The first example which we will discuss is sealevel.c. This sample program starts the Data Explorer user interface in -image mode, and then loads a visual program (see Figure 12).

Figure 12. sealevel.net

#include <stdio.h>
#include "dx/dxl.h"
#ifndef BASE
#define BASE "/usr/lpp/dx"
#endif
/*
 * define an error handler
 */
void ErrorHandler(DXLConnection *conn, const char *msg, void *data)
{
    printf("DXL Error: %s\n", msg);
}
main(int argc, char *argv[])
{
    DXLConnection *conn = NULL;
    char result[100];
    /*
     * Start Data Explorer in -image mode with certain menus disabled.
     */
    conn = DXLStartDX(
              "dx -image -noExitOptions -noExecuteMenus -noConnectionMenus",
              NULL);
    if (conn == NULL)
    {
        fprintf(stderr,"Could not connect\n");
        perror("DXLStartDX");
        exit(1);
    }
    /*
     * Set the error handler
     */
    DXLSetErrorHandler(conn, ErrorHandler, NULL);
    /*
     * Load the visual program to run
     */
    DXLLoadVisualProgram(conn, BASE"/samples/dxlink/sealevel.net");
    /*
     * Set the value of the DXLInput tool which is labelled
     * "contour_line_value" and execute.
     */
    DXLSetValue(conn, "contour_line_value", "0");
    DXLExecuteOnce(conn);
    /*
     * Set the value of the DXLInput tool which is labelled
     * "contour_line_value" and execute.
     */
    DXLSetValue(conn, "contour_line_value", "2");
    DXLExecuteOnce(conn);
    /*
     * Set the value of the DXLInput tool which is labelled
     * "contour_line_value" and execute.
     */
    DXLSetValue(conn, "contour_line_value", "5");
    DXLExecuteOnce(conn);
    /*
     * Set the value of the DXLInput tool which is labelled
     * "contour_line_value" and execute.
     */
    DXLSetValue(conn, "contour_line_value", "20");
    DXLExecuteOnce(conn);
    /*
     * Set the value of the DXLInput tool which is labelled
     * "contour_line_value" and execute.
     */
    DXLSetValue(conn, "contour_line_value", "50");
    DXLExecuteOnce(conn);
    printf("An image window will appear\n");
    printf("and a sequence of images will be created.\n");
    printf("When you are finished, hit return to quit:");
    gets(result);
    DXLExitDX(conn);
}