Added Parameters to SimplePageChangeListener

app/src/main/java/org/kiwix/kiwixmobile/intro/IntroActivity.kt

@@ -20,16 +20,17 @@ package org.kiwix.kiwixmobile.intro
 import android.os.Bundle
 import android.os.Handler
 import android.view.View
-import android.widget.ImageView
+import androidx.core.view.isVisible
 import androidx.viewpager.widget.ViewPager
-import androidx.viewpager.widget.ViewPager.OnPageChangeListener
 import kotlinx.android.synthetic.main.activity_intro.*
+import kotlinx.android.synthetic.main.item_intro_2.airplane
 import org.kiwix.kiwixmobile.R
 import org.kiwix.kiwixmobile.core.Intents.internal
 import org.kiwix.kiwixmobile.core.base.BaseActivity
 import org.kiwix.kiwixmobile.core.di.components.CoreComponent
 import org.kiwix.kiwixmobile.core.main.CoreMainActivity
 import org.kiwix.kiwixmobile.kiwixActivityComponent
+import org.kiwix.kiwixmobile.zim_manager.SimplePageChangeListener
 import java.util.Timer
 import java.util.TimerTask
 import javax.inject.Inject
@@ -47,33 +48,9 @@ class IntroActivity : BaseActivity(), IntroContract.View {
 
   @Inject
   internal lateinit var presenter: IntroContract.Presenter
-  private lateinit var airPlane: ImageView
   private var currentPage = 0
   private lateinit var views: Array<View>
 
-  @Suppress("EmptyFunctionBlock")
-  private val pageChangeListener: OnPageChangeListener = object : OnPageChangeListener {
-    override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {
-    }
-
-    override fun onPageSelected(position: Int) {
-      if (position == 1) {
-        airPlane.visibility = View.VISIBLE
-        airPlane.animate().translationX(airPlane.width.toFloat()).duration = animationDuration
-      } else {
-        airPlane.visibility = View.INVISIBLE
-        airPlane.animate().translationX(-airPlane.width.toFloat())
-      }
-      currentPage = position
-    }
-
-    override fun onPageScrollStateChanged(state: Int) {
-      if (state == ViewPager.SCROLL_STATE_DRAGGING) {
-        dismissAutoRotate()
-      }
-    }
-  }
-
   override fun injection(coreComponent: CoreComponent) {
     this.kiwixActivityComponent.inject(this)
   }
@@ -86,23 +63,21 @@ class IntroActivity : BaseActivity(), IntroContract.View {
       layoutInflater.inflate(R.layout.item_intro_1, view_pager, false),
       layoutInflater.inflate(R.layout.item_intro_2, view_pager, false)
     )
-    val introPagerAdapter = IntroPagerAdapter(views)
-    view_pager.adapter = introPagerAdapter
+    view_pager.run {
+      adapter = IntroPagerAdapter(views)
+      addOnPageChangeListener(SimplePageChangeListener(::updateView, ::handleDraggingState))
+    }
     tab_indicator.setViewPager(view_pager)
-    airPlane = views[1].findViewById(R.id.airplane)
-    view_pager.addOnPageChangeListener(pageChangeListener)
     timer.schedule(object : TimerTask() {
       override fun run() {
         handler.post {
-          if (currentPage == views.size) {
-            currentPage = 0
-          }
+          if (currentPage == views.size) currentPage = 0
           view_pager.setCurrentItem(currentPage++, true)
         }
       }
     }, timerDelay, timerPeriod)
     views.forEach {
-      it.findViewById<View>(R.id.root).setOnClickListener { dismissAutoRotate() }
+      it.setOnClickListener { dismissAutoRotate() }
     }
   }
 
@@ -111,7 +86,7 @@ class IntroActivity : BaseActivity(), IntroContract.View {
     handler.removeCallbacksAndMessages(null)
     timer.cancel()
     views.forEach {
-      it.findViewById<View>(R.id.root).setOnClickListener(null)
+      it.setOnClickListener(null)
     }
   }
 
@@ -122,6 +97,19 @@ class IntroActivity : BaseActivity(), IntroContract.View {
     finish()
   }
 
+  private fun updateView(position: Int) {
+    airplane.isVisible = position == 1
+    if (position == 1)
+      airplane.animate().translationX(airplane.width.toFloat()).duration = animationDuration
+    else
+      airplane.animate().translationX(-airplane.width.toFloat())
+    currentPage = position
+  }
+
+  private fun handleDraggingState(state: Int) {
+    if (state == ViewPager.SCROLL_STATE_DRAGGING) dismissAutoRotate()
+  }
+
   private fun dismissAutoRotate() {
     handler.removeCallbacksAndMessages(null)
     timer.cancel()

app/src/main/java/org/kiwix/kiwixmobile/zim_manager/SimplePageChangeListener.kt

@@ -20,8 +20,10 @@ package org.kiwix.kiwixmobile.zim_manager
 
 import androidx.viewpager.widget.ViewPager.OnPageChangeListener
 
-class SimplePageChangeListener(private val onPageSelectedAction: (Int) -> Unit) :
-  OnPageChangeListener {
+class SimplePageChangeListener @JvmOverloads constructor(
+  private val onPageSelectedAction: (Int) -> Unit,
+  private val onPageScrollStateChanged: ((Int) -> Unit)? = null
+) : OnPageChangeListener {
   override fun onPageScrolled(
     position: Int,
     positionOffset: Float,
@@ -34,5 +36,6 @@ class SimplePageChangeListener(private val onPageSelectedAction: (Int) -> Unit)
   }
 
   override fun onPageScrollStateChanged(state: Int) {
+    onPageScrollStateChanged?.invoke(state)
   }
 }

app/src/main/res/layout/item_intro_1.xml

@@ -1,7 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:app="http://schemas.android.com/apk/res-auto"
-  android:id="@+id/root"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:padding="24dp">

app/src/main/res/layout/item_intro_2.xml

@@ -1,7 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:app="http://schemas.android.com/apk/res-auto"
-  android:id="@+id/root"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:padding="24dp">