Fixed various bugs

These are:
* different size of addContact- and SettingsButton
* default icons in light mode for users and groups (even though they are
currently just the version used in dark mode)
* wrong preferred size of unnamed "Login" label in LoginScene
* unopenable LoginScene for some OS (Debian)
* white screen when the current scene is switched

Additionally cleaned up code a bit in MessageControl and
LoginScene(.java)

client/src/main/java/envoy/client/ui/SceneContext.java

@@ -4,6 +4,7 @@ import java.io.IOException;
 import java.util.Stack;
 import java.util.logging.Level;
 
+import javafx.application.Platform;
 import javafx.fxml.FXMLLoader;
 import javafx.scene.Parent;
 import javafx.scene.Scene;
@@ -125,10 +126,11 @@ public final class SceneContext {
 
 			sceneStack.push(scene);
 			stage.setScene(scene);
-			if (sceneInfo == SceneInfo.LOGIN_SCENE) stage.setResizable(false);
-			else stage.setResizable(true);
+			// The LoginScene is the only scene not intended to be resized
+			// As strange as it seems, this is needed as otherwise the LoginScene won't be
+			// displayed on some OS (...Debian...)
+			Platform.runLater(() -> stage.setResizable(sceneInfo != SceneInfo.LOGIN_SCENE));
 			applyCSS();
-			stage.sizeToScene();
 			stage.show();
 		} catch (final IOException e) {
 			EnvoyLog.getLogger(SceneContext.class).log(Level.SEVERE, String.format("Could not load scene for %s: ", sceneInfo), e);

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

@@ -136,23 +136,23 @@ public final class LoginScene {
 
 	@FXML
 	private void registerSwitchPressed() {
-		registration = !registration;
-
-		// Make repeat password field and label visible / invisible
-		repeatPasswordField.setVisible(registration);
-		if (loginButton.getText().equals("Login")) {
+		if (!registration) {
+			// case if the current mode is login
 			loginButton.setText("Register");
 			loginButton.setPadding(new Insets(2, 116, 2, 116));
 			registerTextLabel.setText("Already an account?");
 			registerSwitch.setText("Login");
-			offlineModeButton.setDisable(true);
 		} else {
+			// case if the current mode is registration
 			loginButton.setText("Login");
 			loginButton.setPadding(new Insets(2, 125, 2, 125));
 			registerTextLabel.setText("No account yet?");
 			registerSwitch.setText("Register");
-			offlineModeButton.setDisable(false);
 		}
+		registration = !registration;
+		// Make repeat password field and label visible / invisible
+		repeatPasswordField.setVisible(registration);
+		offlineModeButton.setDisable(registration);
 	}
 
 	@FXML
@@ -167,7 +167,7 @@ public final class LoginScene {
 			localDB.setUser(localDB.getUsers().get(identifier));
 			localDB.initializeUserStorage();
 			localDB.loadUserData();
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			// User storage empty, wrong user name etc. -> default lastSync
 		}
 		return localDB.getLastSync();
@@ -190,7 +190,7 @@ public final class LoginScene {
 		try {
 			// Try entering offline mode
 			localDB.loadUsers();
-			final User clientUser = (User) localDB.getUsers().get(credentials.getIdentifier());
+			final User clientUser = localDB.getUsers().get(credentials.getIdentifier());
 			if (clientUser == null) throw new EnvoyException("Could not enter offline mode: user name unknown");
 			client.setSender(clientUser);
 			loadChatScene();

client/src/main/java/envoy/client/ui/listcell/MessageControl.java

@@ -40,8 +40,9 @@ import envoy.util.EnvoyLog;
  */
 public class MessageControl extends Label {
 
-	private static LocalDB	localDB;
-	private boolean		ownMessage;
+	private boolean ownMessage;
+
+	private static LocalDB localDB;
 
 	private static final DateTimeFormatter			dateFormat		= DateTimeFormatter.ofPattern("dd.MM.yyyy HH:mm:ss")
 		.withZone(ZoneId.systemDefault());
@@ -57,7 +58,7 @@ public class MessageControl extends Label {
 		// Creating the underlying VBox and the dateLabel
 		final var hbox = new HBox();
 		if (message.getSenderID() != localDB.getUser().getID() && message instanceof GroupMessage) {
-			Label label = new Label();
+			final var label = new Label();
 			label.getStyleClass().add("groupMemberNames");
 			label.setText(localDB.getUsers()
 				.values()
@@ -73,12 +74,12 @@ public class MessageControl extends Label {
 		final var vbox = new VBox(hbox);
 
 		// Creating the actions for the MenuItems
-		final ContextMenu	contextMenu		= new ContextMenu();
-		final MenuItem		copyMenuItem	= new MenuItem("Copy");
-		final MenuItem		deleteMenuItem	= new MenuItem("Delete");
-		final MenuItem		forwardMenuItem	= new MenuItem("Forward");
-		final MenuItem		quoteMenuItem	= new MenuItem("Quote");
-		final MenuItem		infoMenuItem	= new MenuItem("Info");
+		final var	contextMenu		= new ContextMenu();
+		final var	copyMenuItem	= new MenuItem("Copy");
+		final var	deleteMenuItem	= new MenuItem("Delete");
+		final var	forwardMenuItem	= new MenuItem("Forward");
+		final var	quoteMenuItem	= new MenuItem("Quote");
+		final var	infoMenuItem	= new MenuItem("Info");
 		copyMenuItem.setOnAction(e -> copyMessage(message));
 		deleteMenuItem.setOnAction(e -> deleteMessage(message));
 		forwardMenuItem.setOnAction(e -> forwardMessage(message));
@@ -109,13 +110,13 @@ public class MessageControl extends Label {
 		final var textLabel = new Label(message.getText());
 		textLabel.setMaxWidth(430);
 		textLabel.setWrapText(true);
-		HBox hBoxBottom = new HBox();
+		final var hBoxBottom = new HBox();
 		hBoxBottom.getChildren().add(textLabel);
 		// Setting the message status icon and background color
 		if (message.getSenderID() == localDB.getUser().getID()) {
 			final var statusIcon = new ImageView(statusImages.get(message.getStatus()));
 			statusIcon.setPreserveRatio(true);
-			Region space = new Region();
+			final var space = new Region();
 			HBox.setHgrow(space, Priority.ALWAYS);
 			hBoxBottom.getChildren().add(space);
 			hBoxBottom.getChildren().add(statusIcon);
@@ -156,5 +157,10 @@ public class MessageControl extends Label {
 	 */
 	public static void setLocalDB(LocalDB localDB) { MessageControl.localDB = localDB; }
 
+	/**
+	 * @return whether the message stored by this {@code MessageControl} has been
+	 *         sent by this user of Envoy
+	 * @since Envoy Client v0.1-beta
+	 */
 	public boolean isOwnMessage() { return ownMessage; }
 }