diff --git a/PHDemo/PHDemo/DemoToastVC.swift b/PHDemo/PHDemo/DemoToastVC.swift
index 7e2cfec..9245347 100644
--- a/PHDemo/PHDemo/DemoToastVC.swift
+++ b/PHDemo/PHDemo/DemoToastVC.swift
@@ -118,6 +118,12 @@ class DemoToastVC: ListVC {
             section.add(title: "标题 + 正文") {
                 TestToast(.title(title).message(message))
             }
+            section.add(title: "防止重复") {
+                TestToast(.identifier("toast").title(title).message(message).duration(2))
+                DispatchQueue.main.asyncAfter(deadline: .now() + 1) {
+                    TestToast(.identifier("toast").title(title).message(message).duration(2))
+                }
+            }
             section.add(title: "一段长文本") {
                 // Toast(.message(message))
                 // 可以简写成这样：
diff --git a/Sources/ProHUD/Alert/AlertTarget.swift b/Sources/ProHUD/Alert/AlertTarget.swift
index ff6335e..0b11ec3 100644
--- a/Sources/ProHUD/Alert/AlertTarget.swift
+++ b/Sources/ProHUD/Alert/AlertTarget.swift
@@ -73,8 +73,12 @@ open class AlertTarget: BaseController, HUDTargetType {
     
     /// 视图模型
     @objc public var vm: AlertViewModel? {
+        willSet {
+            vm?.cancelTimer()
+        }
         didSet {
             vm?.vc = self
+            vm?.restartTimer()
         }
     }
     
diff --git a/Sources/ProHUD/Capsule/CapsuleTarget.swift b/Sources/ProHUD/Capsule/CapsuleTarget.swift
index a1463ca..62781d5 100644
--- a/Sources/ProHUD/Capsule/CapsuleTarget.swift
+++ b/Sources/ProHUD/Capsule/CapsuleTarget.swift
@@ -48,6 +48,7 @@ open class CapsuleTarget: BaseController, HUDTargetType {
         }
         didSet {
             vm?.vc = self
+            vm?.restartTimer()
         }
     }
     
diff --git a/Sources/ProHUD/Toast/ToastTarget.swift b/Sources/ProHUD/Toast/ToastTarget.swift
index 8417e35..f7d96f6 100644
--- a/Sources/ProHUD/Toast/ToastTarget.swift
+++ b/Sources/ProHUD/Toast/ToastTarget.swift
@@ -83,8 +83,12 @@ open class ToastTarget: BaseController, HUDTargetType {
     
     /// 视图模型
     @objc public var vm: ToastViewModel? {
+        willSet {
+            vm?.cancelTimer()
+        }
         didSet {
             vm?.vc = self
+            vm?.restartTimer()
         }
     }