Hi,
If I implement a new navigation command I have to update the NavigationCommandFactory in my local udig environment. With the next udig version I have the problem to fix it there again.
Therefore I tried it another way, I used the ZoomCommand:
double newScaleDenominator = ...
double oldScaleDenominator = map.getViewportModel().getScaleDenominator();
double zoomfactor = oldScaleDenominator / newScaleDenominator ;
map.sendCommandSync(NavigationCommandFactory.getInstance().createZoomCommand(zoomfactor));
It works but its not quite precise. if the scaledenominator is 87'000'000 and the new one is 43'000'000 (zoomfactor ~2) the resulting scaledenominator is about 67'000'000. In the ZoomCommand class I read that this command works on viewport width and height, this must be the reason.
The next try was using the ViewportModel of the map:
map.getViewportModelInternal.setScale(scaleDenominator);
map.getRenderManagerInternal()refresh(null);
but this doesn't work reliable: sometimes it just renders the map with the old scaledenominator, sometimes with the new one. and it takes up to four seconds untill it starts rendering.
for the moment i will use the zoomcommand with a callback wich changes the slider position after rendering :-)
tony roth
You will have to make your own NavCommand. I think you extend AbstractNavCommand and make the following call in the run method:
map.getViewportModelInternal().setScaleDenominator( scale ).
Don't for get to add the undo functionality.
Jesse
Hi list,
some of my users don't want to use the text field below the map for setting the scale (denominator) nor want they use the zoom in or zoom out action. Therfore I will give them a slider widget with which they can set the scale from 1:10.000 to 1:1.000.000 (or something like that).
But how do I set the scale denominator for the actual map. I found no NavigationCommand for this. I checked the NavigationCommandFactory.getInstance.create... commands where I already use the ViewportCenterCommand for annother gimmick.
Can somehone help me with this?
thanks,
tony roth
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