diff --git a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/Account.java b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/Account.java
index 8eaf538cd..585f45e80 100644
--- a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/Account.java
+++ b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/Account.java
@@ -17,8 +17,13 @@
  */
 package org.jackhuang.hmcl.auth;
 
+import org.jackhuang.hmcl.util.ObservableHelper;
 import org.jackhuang.hmcl.util.ToStringBuilder;
 
+import javafx.application.Platform;
+import javafx.beans.InvalidationListener;
+import javafx.beans.Observable;
+
 import java.util.Map;
 import java.util.Optional;
 import java.util.UUID;
@@ -27,7 +32,7 @@ import java.util.UUID;
  *
  * @author huangyuhui
  */
-public abstract class Account {
+public abstract class Account implements Observable {
 
     /**
      * @return the name of the account who owns the character
@@ -66,6 +71,26 @@ public abstract class Account {
 
     public abstract void clearCache();
 
+    private ObservableHelper helper = new ObservableHelper(this);
+
+    @Override
+    public void addListener(InvalidationListener listener) {
+        helper.addListener(listener);
+    }
+
+    @Override
+    public void removeListener(InvalidationListener listener) {
+        helper.removeListener(listener);
+    }
+
+    /**
+     * Called when the account has changed.
+     * This method can be called from any thread.
+     */
+    protected void invalidate() {
+        Platform.runLater(helper::invalidate);
+    }
+
     @Override
     public String toString() {
         return new ToStringBuilder(this)
diff --git a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/yggdrasil/YggdrasilAccount.java b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/yggdrasil/YggdrasilAccount.java
index 112bdfc3c..4d47c1f8f 100644
--- a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/yggdrasil/YggdrasilAccount.java
+++ b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/yggdrasil/YggdrasilAccount.java
@@ -114,6 +114,7 @@ public class YggdrasilAccount extends Account {
         }
 
         this.characterUUID = this.session.getSelectedProfile().getId();
+        invalidate();
     }
 
     @Override
diff --git a/HMCLCore/src/main/java/org/jackhuang/hmcl/util/ObservableHelper.java b/HMCLCore/src/main/java/org/jackhuang/hmcl/util/ObservableHelper.java
new file mode 100644
index 000000000..c4b8e3dd9
--- /dev/null
+++ b/HMCLCore/src/main/java/org/jackhuang/hmcl/util/ObservableHelper.java
@@ -0,0 +1,65 @@
+/*
+ * Hello Minecraft! Launcher.
+ * Copyright (C) 2018  huangyuhui <huanghongxun2008@126.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see {http://www.gnu.org/licenses/}.
+ */
+package org.jackhuang.hmcl.util;
+
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+import javafx.beans.InvalidationListener;
+import javafx.beans.Observable;
+
+/**
+ * Helper class for implementing {@link Observable}.
+ *
+ * @author yushijinhun
+ */
+public class ObservableHelper implements Observable, InvalidationListener {
+
+    private List<InvalidationListener> listeners = new CopyOnWriteArrayList<>();
+    private Observable source;
+
+    public ObservableHelper(Observable source) {
+        this.source = source;
+    }
+
+    /**
+     * This method can be called from any thread.
+     */
+    @Override
+    public void addListener(InvalidationListener listener) {
+        listeners.add(listener);
+    }
+
+    /**
+     * This method can be called from any thread.
+     */
+    @Override
+    public void removeListener(InvalidationListener listener) {
+        listeners.remove(listener);
+    }
+
+    public void invalidate() {
+        listeners.forEach(it -> it.invalidated(source));
+    }
+
+    @Override
+    public void invalidated(Observable observable) {
+        this.invalidate();
+    }
+
+}