diff --git a/.gitignore b/.gitignore
index fd45b12..2aa3836 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,7 +5,9 @@
 /.idea/libraries
 /.idea/modules.xml
 /.idea/workspace.xml
+gradle/
 .DS_Store
 /build
 /captures
 .externalNativeBuild
+.idea/
diff --git a/README.en.md b/README.en.md
index 93c6b45..57ed437 100644
--- a/README.en.md
+++ b/README.en.md
@@ -24,7 +24,7 @@ implementation 'com.tongtonglock:ttlock:3.0.6'
 ```
 <uses-permission android:name="android.permission.BLUETOOTH"/>
 <uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
-<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
+<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
 <uses-permission android:name="android.permission.INTERNET"/>
 <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
 ```
diff --git a/README.md b/README.md
index c208f33..48ccba7 100644
--- a/README.md
+++ b/README.md
@@ -26,7 +26,7 @@ implementation 'com.tongtonglock:ttlock:3.0.6'
 ```
 <uses-permission android:name="android.permission.BLUETOOTH" />
 <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
-<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
+<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
 <uses-permission android:name="android.permission.INTERNET" />
 <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
 ```
diff --git a/app/build.gradle b/app/build.gradle
index c2b76fa..6ce48b7 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -51,3 +51,4 @@ dependencies {
     implementation 'com.squareup.retrofit2:retrofit:2.4.0'
     implementation 'com.squareup.retrofit2:converter-gson:2.4.0'
 }
+
diff --git a/app/local.properties b/app/local.properties
new file mode 100644
index 0000000..75a20f8
--- /dev/null
+++ b/app/local.properties
@@ -0,0 +1,8 @@
+## This file must *NOT* be checked into Version Control Systems,
+# as it contains information specific to your local configuration.
+#
+# Location of the SDK. This is only used by Gradle.
+# For customization when using a Version Control System, please read the
+# header note.
+#Fri May 15 08:53:19 CST 2020
+sdk.dir=D\:\\Users\\Administrator\\AppData\\Local\\Android\\sdk
diff --git a/app/src/main/java/ttlock/demo/gateway/GatewayActivity.java b/app/src/main/java/ttlock/demo/gateway/GatewayActivity.java
index 3a7fb80..84b805f 100644
--- a/app/src/main/java/ttlock/demo/gateway/GatewayActivity.java
+++ b/app/src/main/java/ttlock/demo/gateway/GatewayActivity.java
@@ -60,8 +60,8 @@ private void initListener() {
      */
     @TargetApi(Build.VERSION_CODES.M)
     private void startScan(){
-        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
-            requestPermissions(new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, REQUEST_PERMISSION_REQ_CODE);
+        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
+            requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_PERMISSION_REQ_CODE);
             return;
         }
         getScanGatewayCallback();
@@ -98,7 +98,7 @@ public void onRequestPermissionsResult(int requestCode, @NonNull String[] permis
                 if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                     getScanGatewayCallback();
                 } else {
-                    if (permissions[0].equals(Manifest.permission.ACCESS_COARSE_LOCATION)){
+                    if (permissions[0].equals(Manifest.permission.ACCESS_FINE_LOCATION)){
 
                     }
                 }
diff --git a/app/src/main/java/ttlock/demo/lock/ScanLockActivity.java b/app/src/main/java/ttlock/demo/lock/ScanLockActivity.java
index bdf1024..22537a2 100644
--- a/app/src/main/java/ttlock/demo/lock/ScanLockActivity.java
+++ b/app/src/main/java/ttlock/demo/lock/ScanLockActivity.java
@@ -93,8 +93,8 @@ private void initListener(){
      */
     @TargetApi(Build.VERSION_CODES.M)
     private void startScan(){
-        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
-            requestPermissions(new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, REQUEST_PERMISSION_REQ_CODE);
+        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
+            requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_PERMISSION_REQ_CODE);
             return;
         }
 
@@ -133,7 +133,7 @@ public void onRequestPermissionsResult(int requestCode, @NonNull String[] permis
                 if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                     getScanLockCallback();
                 } else {
-                    if (permissions[0].equals(Manifest.permission.ACCESS_COARSE_LOCATION)){
+                    if (permissions[0].equals(Manifest.permission.ACCESS_FINE_LOCATION)){
 
                     }
                 }
diff --git a/app/src/main/java/ttlock/demo/wireless_keyboard/WirelessKeyboardActivity.java b/app/src/main/java/ttlock/demo/wireless_keyboard/WirelessKeyboardActivity.java
index 0c5faf8..4f5d3a0 100644
--- a/app/src/main/java/ttlock/demo/wireless_keyboard/WirelessKeyboardActivity.java
+++ b/app/src/main/java/ttlock/demo/wireless_keyboard/WirelessKeyboardActivity.java
@@ -75,8 +75,8 @@ private void initListener(){
      */
     @TargetApi(Build.VERSION_CODES.M)
     private void startScan(){
-        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
-            requestPermissions(new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, REQUEST_PERMISSION_REQ_CODE);
+        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
+            requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_PERMISSION_REQ_CODE);
             return;
         }
 
@@ -143,7 +143,7 @@ public void onRequestPermissionsResult(int requestCode, @NonNull String[] permis
                 if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                     getScanWirelessKeyboardCallback();
                 } else {
-                    if (permissions[0].equals(Manifest.permission.ACCESS_COARSE_LOCATION)){
+                    if (permissions[0].equals(Manifest.permission.ACCESS_FINE_LOCATION)){
 
                     }
                 }
diff --git a/build.gradle b/build.gradle
index ab39209..ce3d1e0 100644
--- a/build.gradle
+++ b/build.gradle
@@ -6,7 +6,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.3.1'
+        classpath 'com.android.tools.build:gradle:3.4.1'
 
         classpath 'com.github.dcendents:android-maven-gradle-plugin:1.5'
         classpath 'com.jfrog.bintray.gradle:gradle-bintray-plugin:1.7.3'
@@ -31,10 +31,10 @@ ext {
     // Support library and architecture components support minSdk 14 and above.
     minSdkVersion = 18
     targetSdkVersion = 23
-    compileSdkVersion = 27
-    buildToolsVersion = '27.0.3'
+    compileSdkVersion = 28
+    buildToolsVersion = '28.0.3'
     // App dependencies
-    supportLibraryVersion = '27.1.1'
+    supportLibraryVersion = '28.0.0'
     lifecycle_version = "1.1.1"
 }