<多次刷新后界面错乱，修改为将fragment直接replace重建>

app/src/main/java/com/wdkl/infoboardclassic/MainActivity.java

@@ -6,6 +6,7 @@ import androidx.fragment.app.FragmentManager;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
+import android.util.Log;
 import android.view.Window;
 import android.view.WindowManager;
 import android.widget.TextView;
@@ -86,9 +87,11 @@ public class MainActivity extends AppCompatActivity {
                         activity.mHandler.sendEmptyMessageDelayed(MSG_UPDATE_ROOM_INFO, 20*1000);
                         break;
                     case MSG_UPDATE_ROOM_INFO:
-                        if (activity.roomInfoFragment != null) {
-                            activity.roomInfoFragment.refresh();
-                        }
+                        Log.d("wzl", "update roomInfoFragment");
+                        activity.roomInfoFragment = RoomInfoFragment.newInstance("RoomInfoFragment");
+                        activity.fragmentManager.beginTransaction()
+                                .replace(R.id.info_content, activity.roomInfoFragment, "RoomInfoFragment")
+                                .commit();
                         activity.mHandler.sendEmptyMessageDelayed(MSG_GET_DATE, 40*1000);
                         break;
                 }