private void go() {
String newScale=combo.getText().trim();
try{
double d = nf.parse(newScale.replace(" ","")).doubleValue();
SetScaleCommand command=new SetScaleCommand(d);
this.mapPart.getMap().sendCommandASync(command);
}catch(Exception e){
org.eclipse.swt.graphics.Rectangle start=ZoomingDialog.calculateBounds(combo);
ZoomingDialog.openErrorMessage(start, this.mapPart