X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=blobdiff_plain;f=bundles%2Forg.simantics.modeling%2Fsrc%2Forg%2Fsimantics%2Fmodeling%2Ftypicals%2Frules%2FPageSettingsTypicalRule.java;fp=bundles%2Forg.simantics.modeling%2Fsrc%2Forg%2Fsimantics%2Fmodeling%2Ftypicals%2Frules%2FPageSettingsTypicalRule.java;h=799579377a614aecf4e15aa8e0ceacc241572b56;hb=eeee0f5dd6aed683ec915f46811c577e30593cfc;hp=4ee96f75d8e062fad53dea40bc81e30c997e5b2a;hpb=f93d655be757bc3ccea8f2733a00eab1bd065351;p=simantics%2Fplatform.git

diff --git a/bundles/org.simantics.modeling/src/org/simantics/modeling/typicals/rules/PageSettingsTypicalRule.java b/bundles/org.simantics.modeling/src/org/simantics/modeling/typicals/rules/PageSettingsTypicalRule.java
index 4ee96f75d..799579377 100644
--- a/bundles/org.simantics.modeling/src/org/simantics/modeling/typicals/rules/PageSettingsTypicalRule.java
+++ b/bundles/org.simantics.modeling/src/org/simantics/modeling/typicals/rules/PageSettingsTypicalRule.java
@@ -23,7 +23,14 @@ public enum PageSettingsTypicalRule implements ITypicalSynchronizationRule {
 
 	@Override
 	public boolean synchronize(WriteGraph graph, Resource template, Resource instance, TypicalInfo info) throws DatabaseException {
+		// Diagrams should always have some sort of diagram description.
+		// If the template doesn't have one, the existing description
+		// from the instance shall not be removed.
 		DiagramDesc mdesc = graph.syncRequest(DiagramRequests.getDiagramDesc(template));
+		if (mdesc == null) {
+			info.messageLog.add("\t\ttemplate doesn't have any diagram page settings, doing nothing");
+			return false;
+		}
 		DiagramDesc idesc = graph.syncRequest(DiagramRequests.getDiagramDesc(instance));
 		if (mdesc.equals(idesc))
 			return false;