diff --git a/android/build.gradle b/android/build.gradle
index 55fa50df..59ef28e3 100644
--- a/android/build.gradle
+++ b/android/build.gradle
@@ -1,7 +1,7 @@
 buildscript {
     repositories {
-        jcenter { url "http://jcenter.bintray.com/" }
-        maven {url "http://repo.spring.io/plugins-release/"}
+        jcenter { url "https://jcenter.bintray.com/" }
+        maven {url "https://repo.spring.io/plugins-release/"}
         mavenCentral()
         maven {
             // All of React Native (JS, Obj-C sources, Android binaries) is installed from npm
@@ -20,7 +20,7 @@ buildscript {
 apply plugin: 'com.android.library'
 
 android {
-    compileSdkVersion 28
+    compileSdkVersion 30
     buildToolsVersion "28.0.3"
 
     defaultConfig {
@@ -40,8 +40,8 @@ android {
 }
 
 repositories {
-    jcenter { url "http://jcenter.bintray.com/" }
-    maven {url "http://repo.spring.io/plugins-release/"}
+    jcenter { url "https://jcenter.bintray.com/" }
+    maven {url "https://repo.spring.io/plugins-release/"}
     mavenCentral()
     maven {
         // All of React Native (JS, Obj-C sources, Android binaries) is installed from npm
@@ -55,6 +55,6 @@ repositories {
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
     implementation 'com.facebook.react:react-native:+'  // From node_modules
-    implementation group: 'com.android.support', name: 'support-v4', version: '27.0.0'
+    implementation 'androidx.core:core:1.12.0'
     implementation "com.google.zxing:core:3.3.0"
 }
diff --git a/android/src/main/java/cn/jystudio/bluetooth/RNBluetoothEscposPrinterPackage.java b/android/src/main/java/cn/jystudio/bluetooth/RNBluetoothEscposPrinterPackage.java
index bed59b5c..0a664fc8 100644
--- a/android/src/main/java/cn/jystudio/bluetooth/RNBluetoothEscposPrinterPackage.java
+++ b/android/src/main/java/cn/jystudio/bluetooth/RNBluetoothEscposPrinterPackage.java
@@ -31,4 +31,4 @@ public List<Class<? extends JavaScriptModule>> createJSModules() {
     public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
         return Collections.emptyList();
     }
-}
\ No newline at end of file
+}
diff --git a/android/src/main/java/cn/jystudio/bluetooth/RNBluetoothManagerModule.java b/android/src/main/java/cn/jystudio/bluetooth/RNBluetoothManagerModule.java
index c48a00f8..3ac727bf 100644
--- a/android/src/main/java/cn/jystudio/bluetooth/RNBluetoothManagerModule.java
+++ b/android/src/main/java/cn/jystudio/bluetooth/RNBluetoothManagerModule.java
@@ -10,8 +10,8 @@
 import android.content.IntentFilter;
 import android.content.pm.PackageManager;
 import android.os.Bundle;
-import android.support.v4.app.ActivityCompat;
-import android.support.v4.content.ContextCompat;
+import androidx.core.app.ActivityCompat;
+import androidx.core.content.ContextCompat;
 import android.util.Log;
 import android.widget.Toast;
 
@@ -238,7 +238,7 @@ public void disconnect(String address, final Promise promise){
             promise.reject("BT NOT ENABLED");
         }
 
-	}
+    }
 
     @ReactMethod
     public void unpaire(String address,final Promise promise){
diff --git a/android/src/main/java/cn/jystudio/bluetooth/escpos/command/sdk/PrintPicture.java b/android/src/main/java/cn/jystudio/bluetooth/escpos/command/sdk/PrintPicture.java
index 761b9e42..99d09f53 100644
--- a/android/src/main/java/cn/jystudio/bluetooth/escpos/command/sdk/PrintPicture.java
+++ b/android/src/main/java/cn/jystudio/bluetooth/escpos/command/sdk/PrintPicture.java
@@ -77,10 +77,10 @@ public static byte[] POS_PrintBMP(Bitmap mBitmap, int nWidth, int nMode, int lef
      */
     public static byte[] Print_1D2A(Bitmap bmp) {
 
-			/*
-			 * 使用下传位图打印图片
-			 * 先收完再打印
-			 */
+            /*
+             * 使用下传位图打印图片
+             * 先收完再打印
+             */
         int width = bmp.getWidth();
         int height = bmp.getHeight();
         byte data[] = new byte[1024 * 10];