Close #260

Author: Open Lowcode SAS

src/org/openlowcode/client/graphic/widget/CObjectArrayField.java

@@ -88,6 +88,7 @@ public class CObjectArrayField
 	private CPageInlineAction feedinginlineaction;
 	private CInlineActionDataRef feedinginlineactionoutputdata;
 	private Tooltip tooltip;
+	private boolean keeponlyone;
 
 	/**
 	 * creates an object array field widget from a message from the server
@@ -144,6 +145,7 @@ public CObjectArrayField(MessageReader reader, CPageSignifPath parentpath) throw
 			this.feedinginlineactionoutputdata = new CInlineActionDataRef(reader, this);
 			reader.returnNextEndStructure("INLACT");
 		}
+		this.keeponlyone = reader.returnNextBooleanField("KOO");
 		reader.returnNextEndStructure("OBJARF");
 
 	}
@@ -154,7 +156,8 @@ public CPageNode deepcopyWithCallback(Callback callback) {
 	}
 
 	public ArrayDataElt<ObjectDataElt> getExternalContent(CPageData inputdata, CPageDataRef dataref) {
-		if (dataref==null) return new ArrayDataElt<ObjectDataElt>("INPUTDATA", new ObjectDataEltType());
+		if (dataref == null)
+			return new ArrayDataElt<ObjectDataElt>("INPUTDATA", new ObjectDataEltType());
 		DataElt thiselement = inputdata.lookupDataElementByName(dataref.getName());
 		if (thiselement == null)
 			throw new RuntimeException(String.format("could not find any page data with name = %s", dataref.getName()));
@@ -257,13 +260,14 @@ public DataElt getDataElt(DataEltType type, String eltname, String objectfieldna
 			if (payloadtypeinarray instanceof ObjectDataEltType) {
 				ObjectDataEltType objecttype = (ObjectDataEltType) payloadtypeinarray;
 				ArrayDataElt<ObjectDataElt> output = new ArrayDataElt<ObjectDataElt>(eltname, objecttype);
-				for (int i = 0; i < thiselementarray.getObjectNumber(); i++) {
-					// fields are not sent back
-					ObjectDataElt thisobject = thiselementarray.getObjectAtIndex(i);
-					ObjectDataElt object = new ObjectDataElt(eltname);
-					object.setUID(thisobject.getUID());
-					output.addElement(object);
-				}
+				if (thiselementarray != null)
+					for (int i = 0; i < thiselementarray.getObjectNumber(); i++) {
+						// fields are not sent back
+						ObjectDataElt thisobject = thiselementarray.getObjectAtIndex(i);
+						ObjectDataElt object = new ObjectDataElt(eltname);
+						object.setUID(thisobject.getUID());
+						output.addElement(object);
+					}
 				return output;
 			}
 		}
@@ -280,8 +284,11 @@ public void forceUpdateData(DataElt dataelt) {
 			treated = true;
 		}
 		if (dataelt instanceof ObjectDataElt) {
+			
 			ObjectDataElt element = (ObjectDataElt) dataelt;
+			if (this.keeponlyone) if (thiselementarray.getObjectNumber()==1) thiselementarray.removeObjectAtIndex(0);
 			thiselementarray.addElement(element.deepcopy(thiselementarray.getName()));
+			
 			refreshDisplay();
 			treated = true;
 		}

src/org/openlowcode/server/graphic/widget/SObjectArrayField.java

@@ -50,6 +50,7 @@ public class SObjectArrayField<E extends DataObject<E>>
 		implements
 		SDefaultPath {
 	private boolean inlinefeeding;
+	private boolean keeponlyone;
 	private String label;
 	private String helper;
 	private ArrayDataElt<TObjectDataElt<E>> inputdata;
@@ -99,8 +100,13 @@ public SObjectArrayField(
 		this.inlinefeeding = false;
 		this.fieldtoshow = fieldtoshow;
 		this.activeprofiles = new NamedList<DisplayProfile<E>>();
+		this.keeponlyone = false;
 	}
 
+	public void setKeepOnlyOne() {
+		this.keeponlyone=true;
+	}
+	
 	/**
 	 * adds a display profile to hide some fields
 	 * 
@@ -187,6 +193,7 @@ public void WritePayloadToCDL(MessageWriter writer, SPageData input, SecurityBuf
 		} else {
 			writer.addBooleanField("INF", false);
 		}
+		writer.addBooleanField("KOO",this.keeponlyone);
 	}
 
 	@Override

src/org/openlowcode/tools/structure/ArrayDataElt.java

@@ -69,12 +69,21 @@ public ArrayDataElt(String name, DataEltType arrayelementtype, E[] objectarray)
 	}
 
 	/**
+	 * 
 	 * @return the number of objects in the array
 	 */
 	public int getObjectNumber() {
 		return this.arraycontent.size();
 	}
 
+	/**
+	 * 
+	 * @param index a number between 0 (included) and getObjectNumber (excluded)
+	 */
+	public void removeObjectAtIndex(int index) {
+		this.arraycontent.remove(index);
+	}
+	
 	/**
 	 * @param index
 	 * @return