diff --git a/Android/APIExample/app/src/main/java/io/agora/api/example/common/BaseFragment.java b/Android/APIExample/app/src/main/java/io/agora/api/example/common/BaseFragment.java
index 60233b788..31a650aae 100644
--- a/Android/APIExample/app/src/main/java/io/agora/api/example/common/BaseFragment.java
+++ b/Android/APIExample/app/src/main/java/io/agora/api/example/common/BaseFragment.java
@@ -23,14 +23,16 @@ public void onCreate(@Nullable Bundle savedInstanceState)
 
     protected void showAlert(String message)
     {
-        Context context = getContext();
-        if (context == null) {
-            return;
-        }
+        handler.post(()->{
+            Context context = getContext();
+            if (context == null) {
+                return;
+            }
 
-        new AlertDialog.Builder(context).setTitle("Tips").setMessage(message)
-                .setPositiveButton("OK", (dialog, which) -> dialog.dismiss())
-                .show();
+            new AlertDialog.Builder(context).setTitle("Tips").setMessage(message)
+                    .setPositiveButton("OK", (dialog, which) -> dialog.dismiss())
+                    .show();
+        });
     }
 
     protected final void showLongToast(final String msg)
diff --git a/Android/APIExample/app/src/main/java/io/agora/api/example/common/model/StatisticsInfo.java b/Android/APIExample/app/src/main/java/io/agora/api/example/common/model/StatisticsInfo.java
index dd27ae8c9..903795073 100644
--- a/Android/APIExample/app/src/main/java/io/agora/api/example/common/model/StatisticsInfo.java
+++ b/Android/APIExample/app/src/main/java/io/agora/api/example/common/model/StatisticsInfo.java
@@ -1,6 +1,11 @@
 package io.agora.api.example.common.model;
 
-import io.agora.rtc.IRtcEngineEventHandler.*;
+import io.agora.rtc.IRtcEngineEventHandler.LastmileProbeResult;
+import io.agora.rtc.IRtcEngineEventHandler.LocalAudioStats;
+import io.agora.rtc.IRtcEngineEventHandler.LocalVideoStats;
+import io.agora.rtc.IRtcEngineEventHandler.RemoteAudioStats;
+import io.agora.rtc.IRtcEngineEventHandler.RemoteVideoStats;
+import io.agora.rtc.IRtcEngineEventHandler.RtcStats;
 
 public class StatisticsInfo {
     private LocalVideoStats localVideoStats;
@@ -32,6 +37,9 @@ public void setRtcStats(RtcStats rtcStats) {
     }
 
     public String getLocalVideoStats() {
+        if(localVideoStats == null || localAudioStats == null){
+            return "";
+        }
         StringBuilder builder = new StringBuilder();
         return builder
                 .append(localVideoStats.encodedFrameWidth)
@@ -70,6 +78,9 @@ public String getLocalVideoStats() {
     }
 
     public String getRemoteVideoStats() {
+        if(remoteAudioStats == null || remoteVideoStats == null){
+            return "";
+        }
         StringBuilder builder = new StringBuilder();
         return builder
                 .append(remoteVideoStats.width)
diff --git a/Android/APIExample/app/src/main/java/io/agora/api/example/examples/basic/JoinChannelVideo.java b/Android/APIExample/app/src/main/java/io/agora/api/example/examples/basic/JoinChannelVideo.java
index 4b15052bd..40104bc17 100644
--- a/Android/APIExample/app/src/main/java/io/agora/api/example/examples/basic/JoinChannelVideo.java
+++ b/Android/APIExample/app/src/main/java/io/agora/api/example/examples/basic/JoinChannelVideo.java
@@ -1,5 +1,9 @@
 package io.agora.api.example.examples.basic;
 
+import static io.agora.api.example.common.model.Examples.BASIC;
+import static io.agora.rtc.video.VideoCanvas.RENDER_MODE_HIDDEN;
+import static io.agora.rtc.video.VideoEncoderConfiguration.STANDARD_BITRATE;
+
 import android.content.Context;
 import android.os.Bundle;
 import android.text.TextUtils;
@@ -19,7 +23,6 @@
 import com.yanzhenjie.permission.AndPermission;
 import com.yanzhenjie.permission.runtime.Permission;
 
-import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
@@ -38,14 +41,6 @@
 import io.agora.rtc.video.VideoEncoderConfiguration;
 import io.agora.rtc.video.WatermarkOptions;
 
-import static io.agora.api.example.common.model.Examples.BASIC;
-import static io.agora.rtc.video.VideoCanvas.RENDER_MODE_FIT;
-import static io.agora.rtc.video.VideoCanvas.RENDER_MODE_HIDDEN;
-import static io.agora.rtc.video.VideoEncoderConfiguration.FRAME_RATE.FRAME_RATE_FPS_15;
-import static io.agora.rtc.video.VideoEncoderConfiguration.ORIENTATION_MODE.ORIENTATION_MODE_ADAPTIVE;
-import static io.agora.rtc.video.VideoEncoderConfiguration.STANDARD_BITRATE;
-import static io.agora.rtc.video.VideoEncoderConfiguration.VD_640x360;
-
 /**This demo demonstrates how to make a one-to-one video call*/
 @Example(
         index = 0,
@@ -97,11 +92,11 @@ public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceStat
     }
 
     private void updateLocalStats(){
-        localStats.setText(statisticsInfo.getLocalVideoStats());
+        handler.post(()-> localStats.setText(statisticsInfo.getLocalVideoStats()));
     }
 
     private void updateRemoteStats(){
-        remoteStats.setText(statisticsInfo.getRemoteVideoStats());
+        handler.post(()->remoteStats.setText(statisticsInfo.getRemoteVideoStats()));
     }
 
     @Override