Added support for API-27 and Android Studio 3.1

app/build.gradle

@@ -1,13 +1,11 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 22
-    buildToolsVersion "22.0.1"
-
+    compileSdkVersion 27
     defaultConfig {
         applicationId "com.example.android.devicepolicydemo"
-        minSdkVersion 14
-        targetSdkVersion 22
+        minSdkVersion 19
+        targetSdkVersion 27
         versionCode 1
         versionName "1.0"
     }
@@ -20,5 +18,6 @@ android {
 }
 
 dependencies {
-    compile fileTree(dir: 'libs', include: ['*.jar'])
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    implementation 'com.android.support:appcompat-v7:27.1.1'
 }

app/src/main/AndroidManifest.xml

@@ -5,10 +5,10 @@
 
     <application
         android:icon="@mipmap/ic_launcher"
-        android:label="@string/app_name" >
+        android:label="@string/app_name">
         <activity
             android:name=".DevicePolicyDemoActivity"
-            android:label="@string/app_name" >
+            android:label="@string/app_name">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 

app/src/main/java/com/example/android/devicepolicydemo/DemoDeviceAdminReceiver.java

@@ -13,9 +13,9 @@
  * method onEnabled().
  */
 public class DemoDeviceAdminReceiver extends DeviceAdminReceiver {
-	static final String TAG = "DemoDeviceAdminReceiver";
+    static final String TAG = "DemoDeviceAdminReceiver";
 
-	//TODO: Override onEnabled(), onDisabled()
+    //TODO: Override onEnabled(), onDisabled()
 
     //TODO: Override onPasswordChanged(), onPasswordFailed(), onPasswordSucceeded()
 

app/src/main/java/com/example/android/devicepolicydemo/DevicePolicyDemoActivity.java

@@ -10,7 +10,6 @@
 import android.view.View;
 import android.widget.Button;
 import android.widget.TextView;
-import android.widget.Toast;
 
 public class DevicePolicyDemoActivity extends Activity {
     static final String TAG = DevicePolicyDemoActivity.class.getSimpleName();
@@ -27,12 +26,11 @@ public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
-        instructions = (TextView) findViewById(R.id.instructions);
-        toggleButton = (Button) findViewById(R.id.toggle_device_admin);
+        instructions = findViewById(R.id.instructions);
+        toggleButton = findViewById(R.id.toggle_device_admin);
 
         // Initialize Device Policy Manager service and our receiver class
-        devicePolicyManager = (DevicePolicyManager) getSystemService(
-                Context.DEVICE_POLICY_SERVICE);
+        devicePolicyManager = (DevicePolicyManager) getSystemService(Context.DEVICE_POLICY_SERVICE);
         demoDeviceAdmin = new ComponentName(this, DemoDeviceAdminReceiver.class);
     }
 

build.gradle

@@ -2,10 +2,11 @@
 
 buildscript {
     repositories {
+        google()
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:1.2.3'
+        classpath 'com.android.tools.build:gradle:3.1.0'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
@@ -14,6 +15,11 @@ buildscript {
 
 allprojects {
     repositories {
+        google()
         jcenter()
     }
 }
+
+task clean(type: Delete) {
+    delete rootProject.buildDir
+}

gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.2.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-all.zip