diff --git a/app/src/main/java/com/jiangdg/usbcamera/view/USBCameraActivity.java b/app/src/main/java/com/jiangdg/usbcamera/view/USBCameraActivity.java
index ec85d76..1f28e2d 100644
--- a/app/src/main/java/com/jiangdg/usbcamera/view/USBCameraActivity.java
+++ b/app/src/main/java/com/jiangdg/usbcamera/view/USBCameraActivity.java
@@ -89,15 +89,15 @@ public class USBCameraActivity extends AppCompatActivity implements CameraDialog
             if(! isConnected) {
                 showShortMsg("连接失败，请检查分辨率参数是否正确");
             }
+            showShortMsg("连接成功");
         }
 
         // 与USB设备断开连接
         @Override
         public void onDisConnectDev(UsbDevice device) {
-
+            showShortMsg("连接失败");
         }
     };
-    private FileOutputStream fos;
 
     @Override
     protected void onCreate(@Nullable Bundle savedInstanceState) {
diff --git a/libusbcamera/src/main/java/com/jiangdg/usbcamera/USBCameraManager.java b/libusbcamera/src/main/java/com/jiangdg/usbcamera/USBCameraManager.java
index d5c845a..9c72938 100644
--- a/libusbcamera/src/main/java/com/jiangdg/usbcamera/USBCameraManager.java
+++ b/libusbcamera/src/main/java/com/jiangdg/usbcamera/USBCameraManager.java
@@ -91,6 +91,8 @@ public class USBCameraManager{
                 if(listener != null){
                     listener.onDettachDev(device);
                 }
+                // 释放资源
+                release();
             }
 
             // 当连接到USB Camera时，被回调
@@ -116,8 +118,6 @@ public class USBCameraManager{
                 if(listener != null){
                     listener.onDisConnectDev(device);
                 }
-                // 关闭摄像头
-                closeCamera();
             }
 
             @Override
@@ -131,9 +131,12 @@ public class USBCameraManager{
 
     // 切换分辨率
     public void updateResolution(Activity activity, CameraViewInterface cameraView, int width, int height, final OnPreviewListener mPreviewListener){
+        // 如果分辨率无变化，则无需重启Camera
+        if(previewWidth == width && previewHeight == height){
+            return;
+        }
         this.previewWidth = width;
         this.previewHeight = height;
-
         // 关闭摄像头
         closeCamera();
         // 释放CameraHandler占用的相关资源