implemented basic architecture

client/src/main/java/envoy/client/ui/control/QuickSelectControl.java

@@ -0,0 +1,21 @@
+package envoy.client.ui.control;
+
+import javafx.scene.control.Label;
+
+import envoy.data.User;
+
+/**
+ * @author Maximilian Käfer
+ * @since Envoy Client v0.3-beta
+ */
+public class QuickSelectControl extends Label {
+
+	public QuickSelectControl(User user) {
+		setPrefSize(35, 35);
+		setMaxSize(35, 35);
+		setMinSize(35, 35);
+		setText(user.getName());
+		getStyleClass().add("quick-select");
+	}
+
+}

client/src/main/java/envoy/client/ui/controller/GroupCreationTab.java

@@ -11,7 +11,7 @@ import javafx.scene.layout.HBox;
 
 import envoy.client.data.*;
 import envoy.client.event.BackEvent;
-import envoy.client.ui.control.ContactControl;
+import envoy.client.ui.control.*;
 import envoy.client.ui.listcell.ListCellFactory;
 import envoy.data.*;
 import envoy.event.GroupCreation;
@@ -58,6 +58,9 @@ public class GroupCreationTab implements EventListener {
 	@FXML
 	private HBox errorProceedBox;
 
+	@FXML
+	private ListView<QuickSelectControl> quickSelectList;
+
 	private String name;
 
 	private final LocalDB localDB = Context.getInstance().getLocalDB();
@@ -86,7 +89,10 @@ public class GroupCreationTab implements EventListener {
 	 * @since Envoy Client v0.1-beta
 	 */
 	@FXML
-	private void userListClicked() { createButton.setDisable(userList.getSelectionModel().isEmpty() || groupNameField.getText().isBlank()); }
+	private void userListClicked() {
+		createButton.setDisable(userList.getSelectionModel().isEmpty() || groupNameField.getText().isBlank());
+		quickSelectList.getItems().add(new QuickSelectControl(userList.getSelectionModel().getSelectedItem()));
+	}
 
 	/**
 	 * Checks, whether the {@code createButton} can be enabled because text is

client/src/main/resources/css/dark.css

@@ -83,3 +83,7 @@
 	-fx-text-fill: white;
 	-fx-background-color: transparent;
 }
+
+.quick-select {
+	-fx-background-color: black;
+}

client/src/main/resources/fxml/GroupCreationTab.fxml

@@ -64,6 +64,7 @@
                <Insets bottom="5.0" top="5" />
             </VBox.margin>
          </Label>
+         <ListView fx:id="quickSelectList" orientation="HORIZONTAL" prefHeight="80.0" />
          <ListView id="chat-list" fx:id="userList" focusTraversable="false" onMouseClicked="#userListClicked" prefWidth="316.0" VBox.vgrow="ALWAYS">
             <contextMenu>
                <ContextMenu anchorLocation="CONTENT_TOP_LEFT" />