CGGOOGLEMAPWIDGET_

CGGOOGLEMAPWIDGET__DEFINE
This is a compound widget object that obtains a Google static map from Google Maps
and displays it in the program's draw widget window. It can be used either as a
stand-alone program or to create a map image in draw widget in a larger widget program.

This program implements a subset of the Google Static Map API, which can be found in
more detail here: https://developers.google.com/maps/documentation/staticmaps/. The
program works by building a URL for a map image. A connection to the Internet is
required to then request a map image (in JPEG or PNG format) to be returned from
Goggle Maps. The returned image is then read and loaded into a draw widget window
of the right size for the returned map image. The default is to delete the image file
that is created, but user can also set keywords to retain the image that is downloaded
from Google Maps. Users are able to control button and motion events in the resulting
draw widget with their own event handler module. A cgMap coordinate object is created
to establish a map reference coordinate system on top of the returned map image, allowing
other map information to be drawn on top of the returned map image.

Examples

Used to put two markers on a map of Fort Collins, Colorado, in a stand-alone window::
PRO cgGoogleMapWidget_Test
marker1 = {cgGOOGLEMAPMARKER, 'normal', 'dodger blue', 'A', Ptr_New(40.600), Ptr_New(-105.100)}
marker2 = {cgGOOGLEMAPMARKER, 'normal', 'purple', 'B', Ptr_New(40.605), Ptr_New(-105.105)}
googleObject = Obj_New('cgGoogleMapWidget', MARKERS=[marker1, marker2], MAPTYPE='Terrain')
END

Author

FANNING SOFTWARE CONSULTING::
David W. Fanning
1645 Sheely Drive
Fort Collins, CO 80526 USA
Phone: 970-221-0438
E-mail: david@idlcoyote.com
Coyote's Guide to IDL Programming: http://www.idlcoyote.com

History

Change History::
Written, 25 June 2012. DWF.
Set the RETAIN keyword on the draw widget for UNIX machines. 28 June 2012. DWF.
Beefed up and changed error handling when failing to obtain a map from Google Maps. 28 June 2012. DWF.
Added NoForwardFix keyword to call to cgMap to allow better drawing of markers. 29 June 2012. DWF.
Added the ability to turn markers on or off with VisibleMarkers keyword and property. 29 June 2012. DWF.