Cleaned up the structure of adding/removing crystal items from the tree.

src/main/java/nl/andrewlalis/crystalkeep/control/AddClusterHandler.java

@@ -23,9 +23,6 @@ public class AddClusterHandler implements EventHandler<ActionEvent> {
 		d.setHeaderText(null);
 		d.setTitle("Add Cluster");
 		d.setGraphic(null);
-		d.showAndWait().ifPresent(s -> {
+		d.showAndWait().ifPresent(s -> cluster.addCluster(new Cluster(s.trim())));
-			cluster.addCluster(new Cluster(s.trim()));
-			model.notifyListeners();
-		});
 	}
 }

src/main/java/nl/andrewlalis/crystalkeep/control/AddShardHandler.java

@@ -59,9 +59,6 @@ public class AddShardHandler implements EventHandler<ActionEvent> {
 			}
 			return null;
 		});
-		dialog.showAndWait().ifPresent(shard -> {
+		dialog.showAndWait().ifPresent(cluster::addShard);
-			cluster.addShard(shard);
-			model.notifyListeners();
-		});
 	}
 }

src/main/java/nl/andrewlalis/crystalkeep/control/DeleteItemHandler.java

@@ -7,7 +7,6 @@ import javafx.scene.control.ButtonType;
 import javafx.scene.control.TreeItem;
 import nl.andrewlalis.crystalkeep.model.Cluster;
 import nl.andrewlalis.crystalkeep.model.CrystalItem;
-import nl.andrewlalis.crystalkeep.model.Model;
 import nl.andrewlalis.crystalkeep.model.Shard;
 import nl.andrewlalis.crystalkeep.view.ClusterTreeItem;
 
@@ -15,11 +14,9 @@ import java.util.Optional;
 
 public class DeleteItemHandler implements EventHandler<ActionEvent> {
 	private final TreeItem<CrystalItem> treeItem;
-	private final Model model;
 
-	public DeleteItemHandler(TreeItem<CrystalItem> treeItem, Model model) {
+	public DeleteItemHandler(TreeItem<CrystalItem> treeItem) {
 		this.treeItem = treeItem;
-		this.model = model;
 	}
 
 	@Override
@@ -27,14 +24,15 @@ public class DeleteItemHandler implements EventHandler<ActionEvent> {
 		if (this.treeItem.getParent() != null && this.treeItem.getParent() instanceof ClusterTreeItem) {
 			Optional<ButtonType> result = new Alert(Alert.AlertType.CONFIRMATION, "Are you sure you want to delete this item?").showAndWait();
 			if (result.isPresent() && result.get() == ButtonType.OK) {
-				var cluster = ((ClusterTreeItem) this.treeItem.getParent()).getCluster();
+				ClusterTreeItem parentTreeItem = (ClusterTreeItem) this.treeItem.getParent();
+				var parentCluster = parentTreeItem.getCluster();
 				var item = this.treeItem.getValue();
 				if (item instanceof Shard) {
-					cluster.removeShard((Shard) item);
+					parentCluster.removeShard((Shard) item);
 				} else if (item instanceof Cluster) {
-					cluster.removeCluster((Cluster) item);
+					var cluster = (Cluster) item;
+					parentCluster.removeCluster(cluster);
 				}
-				this.model.notifyListeners();
 			}
 		}
 	}

src/main/java/nl/andrewlalis/crystalkeep/control/MainViewController.java

@@ -43,7 +43,7 @@ public class MainViewController implements ModelListener {
 	}
 
 	private TreeItem<CrystalItem> createNode(Cluster cluster) {
-		ClusterTreeItem node = new ClusterTreeItem(cluster);
+		ClusterTreeItem node = new ClusterTreeItem(cluster, this.clusterTreeView);
 		node.setExpanded(true);
 		for (Cluster child : cluster.getClustersOrdered()) {
 			node.getChildren().add(this.createNode(child));

src/main/java/nl/andrewlalis/crystalkeep/model/Cluster.java

@@ -8,6 +8,7 @@ public class Cluster implements Comparable<Cluster>, CrystalItem {
 	private final Set<Cluster> clusters;
 
 	private Cluster parent;
+	private final Set<ClusterListener> listeners = new HashSet<>();
 
 	public Cluster(String name, Set<Shard> shards, Set<Cluster> clusters) {
 		this.name = name;
@@ -39,21 +40,25 @@ public class Cluster implements Comparable<Cluster>, CrystalItem {
 	public void addShard(Shard shard) {
 		this.shards.add(shard);
 		shard.setParent(this);
+		this.listeners.forEach(l -> l.shardAdded(shard));
 	}
 
 	public void removeShard(Shard shard) {
 		this.shards.remove(shard);
 		shard.setParent(null);
+		this.listeners.forEach(l -> l.shardRemoved(shard));
 	}
 
 	public void addCluster(Cluster cluster) {
 		this.clusters.add(cluster);
 		cluster.setParent(this);
+		this.listeners.forEach(l -> l.clusterAdded(cluster));
 	}
 
 	public void removeCluster(Cluster cluster) {
 		this.clusters.remove(cluster);
 		cluster.setParent(null);
+		this.listeners.forEach(l -> l.clusterRemoved(cluster));
 	}
 
 	public List<Cluster> getClustersOrdered() {
@@ -76,6 +81,14 @@ public class Cluster implements Comparable<Cluster>, CrystalItem {
 		this.parent = parent;
 	}
 
+	public void addListener(ClusterListener listener) {
+		this.listeners.add(listener);
+	}
+
+	public void removeListener(ClusterListener listener) {
+		this.listeners.remove(listener);
+	}
+
 	@Override
 	public int compareTo(Cluster o) {
 		return this.getName().compareTo(o.getName());

src/main/java/nl/andrewlalis/crystalkeep/model/ClusterListener.java

@@ -0,0 +1,8 @@
+package nl.andrewlalis.crystalkeep.model;
+
+public interface ClusterListener {
+	default void clusterAdded(Cluster cluster) {}
+	default void clusterRemoved(Cluster cluster) {}
+	default void shardAdded(Shard shard) {}
+	default void shardRemoved(Shard shard) {}
+}

src/main/java/nl/andrewlalis/crystalkeep/view/ClusterTreeItem.java

@@ -1,18 +1,59 @@
 package nl.andrewlalis.crystalkeep.view;
 
 import javafx.scene.control.TreeItem;
+import javafx.scene.control.TreeView;
 import nl.andrewlalis.crystalkeep.model.Cluster;
+import nl.andrewlalis.crystalkeep.model.ClusterListener;
 import nl.andrewlalis.crystalkeep.model.CrystalItem;
+import nl.andrewlalis.crystalkeep.model.Shard;
 
-public class ClusterTreeItem extends TreeItem<CrystalItem> {
+public class ClusterTreeItem extends TreeItem<CrystalItem> implements ClusterListener {
 	private final Cluster cluster;
+	private final TreeView<CrystalItem> treeView;
 
-	public ClusterTreeItem(Cluster cluster) {
+	public ClusterTreeItem(Cluster cluster, TreeView<CrystalItem> treeView) {
 		super(cluster);
 		this.cluster = cluster;
+		this.treeView = treeView;
+		this.cluster.addListener(this);
 	}
 
 	public Cluster getCluster() {
 		return cluster;
 	}
+
+	@Override
+	public void clusterAdded(Cluster cluster) {
+		var item = new ClusterTreeItem(cluster, treeView);
+		this.getChildren().add(item);
+		this.treeView.getSelectionModel().select(item);
+	}
+
+	@Override
+	public void clusterRemoved(Cluster cluster) {
+		for (var child : this.getChildren()) {
+			if (child.getValue().equals(cluster)) {
+				this.getChildren().remove(child);
+				if (child instanceof ClusterListener) cluster.removeListener((ClusterListener) child);
+				return;
+			}
+		}
+	}
+
+	@Override
+	public void shardAdded(Shard shard) {
+		var item = new ShardTreeItem(shard);
+		this.getChildren().add(item);
+		this.treeView.getSelectionModel().select(item);
+	}
+
+	@Override
+	public void shardRemoved(Shard shard) {
+		for (var child : this.getChildren()) {
+			if (child.getValue().equals(shard)) {
+				this.getChildren().remove(child);
+				return;
+			}
+		}
+	}
 }

src/main/java/nl/andrewlalis/crystalkeep/view/CrystalItemTreeCell.java

@@ -40,7 +40,7 @@ public class CrystalItemTreeCell extends TreeCell<CrystalItem> {
 
 			if (this.getTreeItem().getParent() != null && this.getTreeItem().getParent() instanceof ClusterTreeItem) {
 				var deleteItem = new MenuItem("Delete");
-				deleteItem.setOnAction(new DeleteItemHandler(this.getTreeItem(), this.model));
+				deleteItem.setOnAction(new DeleteItemHandler(this.getTreeItem()));
 				menu.getItems().add(deleteItem);
 			}
 			this.setText(item.getName());