-Replace part of the code with Kotlin

app/build.gradle

@@ -1,4 +1,5 @@
 apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
 
 android {
     compileSdkVersion defCompileSdkVersion
@@ -16,6 +17,10 @@ android {
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
         }
     }
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
 }
 
 dependencies {

app/src/main/AndroidManifest.xml

@@ -7,8 +7,7 @@
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
         android:supportsRtl="true"
-        android:theme="@style/AppTheme"
-        android:name=".SampleApplication">
+        android:theme="@style/AppTheme">
         <activity android:name=".MainActivity"
             android:exported="true">
             <intent-filter>

app/src/main/java/com/getkeepsafe/taptargetviewsample/MainActivity.kt

@@ -0,0 +1,145 @@
+package com.getkeepsafe.taptargetviewsample
+
+import android.content.DialogInterface
+import android.graphics.Rect
+import android.graphics.Typeface
+import android.os.Bundle
+import android.text.SpannableString
+import android.text.style.StyleSpan
+import android.text.style.UnderlineSpan
+import android.util.Log
+import android.view.View
+import android.widget.TextView
+import android.widget.Toast
+import androidx.appcompat.app.AlertDialog
+import androidx.appcompat.app.AppCompatActivity
+import androidx.appcompat.widget.Toolbar
+import androidx.core.content.ContextCompat
+import com.getkeepsafe.taptargetview.TapTarget
+import com.getkeepsafe.taptargetview.TapTargetSequence
+import com.getkeepsafe.taptargetview.TapTargetView
+import com.getkeepsafe.taptargetview.showGuideView
+
+class MainActivity : AppCompatActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_main)
+        val toolbar = findViewById<View>(R.id.toolbar) as Toolbar
+        toolbar.inflateMenu(R.menu.menu_main)
+        toolbar.navigationIcon =
+            ContextCompat.getDrawable(this, R.drawable.ic_arrow_back_white_24dp)
+
+        // We load a drawable and create a location to show a tap target here
+        // We need the display to get the width and height at this point in time
+        val display = windowManager.defaultDisplay
+        // Load our little droid guy
+        val droid = ContextCompat.getDrawable(this, R.drawable.ic_android_black_24dp)
+        // Tell our droid buddy where we want him to appear
+        val droidTarget = Rect(0, 0, droid!!.intrinsicWidth * 2, droid.intrinsicHeight * 2)
+        // Using deprecated methods makes you look way cool
+        droidTarget.offset(display.width / 2, display.height / 2)
+        val sassyDesc = SpannableString("It allows you to go back, sometimes")
+        sassyDesc.setSpan(
+            StyleSpan(Typeface.ITALIC),
+            sassyDesc.length - "sometimes".length,
+            sassyDesc.length,
+            0
+        )
+
+        // We have a sequence of targets, so lets build it!
+        val sequence = TapTargetSequence(this)
+            .addTarget( // This tap target will target the back button, we just need to pass its containing toolbar
+                TapTarget.forToolbarNavigationIcon(toolbar, "This is the back button", sassyDesc)
+                    .id(1),  // Likewise, this tap target will target the search button
+                TapTarget.forToolbarMenuItem(
+                    toolbar,
+                    R.id.search,
+                    "This is a search icon",
+                    "As you can see, it has gotten pretty dark around here..."
+                )
+                    .dimColor(android.R.color.black)
+                    .outerCircleColor(R.color.colorAccent)
+                    .targetCircleColor(android.R.color.black)
+                    .transparentTarget(true)
+                    .textColor(android.R.color.black)
+                    .id(2),  // You can also target the overflow button in your toolbar
+                TapTarget.forToolbarOverflow(
+                    toolbar,
+                    "This will show more options",
+                    "But they're not useful :("
+                ).id(3),  // This tap target will target our droid buddy at the given target rect
+                TapTarget.forBounds(
+                    droidTarget,
+                    "Oh look!",
+                    "You can point to any part of the screen. You also can't cancel this one!"
+                )
+                    .cancelable(false)
+                    .icon(droid)
+                    .id(4)
+            )
+            .listener(object : TapTargetSequence.Listener {
+                // This listener will tell us when interesting(tm) events happen in regards
+                // to the sequence
+                override fun onSequenceFinish() {
+                    (findViewById<View>(R.id.educated) as TextView).text =
+                        "Congratulations! You're educated now!"
+                }
+
+                override fun onSequenceStep(lastTarget: TapTarget?, targetClicked: Boolean) {
+                    Log.d("TapTargetView", "Clicked on " + lastTarget!!.id())
+                }
+
+                override fun onSequenceCanceled(lastTarget: TapTarget?) {
+                    val dialog = AlertDialog.Builder(this@MainActivity)
+                        .setTitle("Uh oh")
+                        .setMessage("You canceled the sequence")
+                        .setPositiveButton("Oops", null).show()
+                    dialog.showGuideView(TapTarget.forView(
+                        dialog.getButton(DialogInterface.BUTTON_POSITIVE),
+                        "Uh oh!",
+                        "You canceled the sequence at step " + lastTarget?.id()
+                    )
+                        .cancelable(false)
+                        .tintTarget(false), object : TapTargetView.Listener() {
+                        override fun onTargetClick(view: TapTargetView) {
+                            super.onTargetClick(view)
+                            dialog.dismiss()
+                        }
+                    })
+                }
+            })
+
+        // You don't always need a sequence, and for that there's a single time tap target
+        val spannedDesc = SpannableString("This is the sample app for TapTargetView")
+        spannedDesc.setSpan(
+            UnderlineSpan(),
+            spannedDesc.length - "TapTargetView".length,
+            spannedDesc.length,
+            0
+        )
+        this.showGuideView(TapTarget.forView(findViewById(R.id.fab), "Hello, world!", spannedDesc)
+            .cancelable(false)
+            .drawShadow(true)
+            .titleTextDimen(R.dimen.title_text_size)
+            .tintTarget(false), object : TapTargetView.Listener() {
+            override fun onTargetClick(view: TapTargetView) {
+                super.onTargetClick(view)
+                // .. which evidently starts the sequence we defined earlier
+                sequence.start()
+            }
+
+            override fun onOuterCircleClick(view: TapTargetView) {
+                super.onOuterCircleClick(view)
+                Toast.makeText(
+                    view.context,
+                    "You clicked the outer circle!",
+                    Toast.LENGTH_SHORT
+                ).show()
+            }
+
+            override fun onTargetDismissed(view: TapTargetView, userInitiated: Boolean) {
+                Log.d("TapTargetViewSample", "You dismissed me :(")
+            }
+        })
+    }
+}

taptargetview/build.gradle

@@ -1,6 +1,7 @@
 plugins {
     id 'com.vanniktech.maven.publish'
     id 'com.android.library'
+    id 'kotlin-android'
 }
 
 android {
@@ -21,7 +22,7 @@ dependencies {
     api("androidx.appcompat:appcompat:$defAppCompatVersion") {
         exclude group: 'androidx.core', module: 'core-ktx'
     }
-    implementation ("androidx.core:core:$defAndroidXCoreVersion") {
+    implementation ("androidx.core:core-ktx:$defAndroidXCoreVersion") {
         exclude group: 'androidx.core', module: 'core-ktx'
     }
     api("org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.8.22") {

taptargetview/src/main/java/com/getkeepsafe/taptargetview/FloatValueAnimatorBuilder.java

@@ -69,12 +69,7 @@ public FloatValueAnimatorBuilder repeat(int times) {
   }
 
   public FloatValueAnimatorBuilder onUpdate(final UpdateListener listener) {
-    animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
-      @Override
-      public void onAnimationUpdate(ValueAnimator animation) {
-        listener.onUpdate((float) animation.getAnimatedValue());
-      }
-    });
+    animator.addUpdateListener(animation -> listener.onUpdate((float) animation.getAnimatedValue()));
     return this;
   }
 

taptargetview/src/main/java/com/getkeepsafe/taptargetview/ReflectExtensions.kt

@@ -0,0 +1,12 @@
+@file:JvmName("ReflectExtensions")
+package com.getkeepsafe.taptargetview
+
+import kotlin.jvm.Throws
+
+@Throws(NoSuchFieldException::class, IllegalAccessException::class)
+fun Any?.getPrivateField(fieldName: String?): Any? {
+    if (fieldName == null || this == null) return null
+    val field = this.javaClass.getDeclaredField(fieldName)
+    field.isAccessible = true
+    return field.get(this)
+}