Fix Part of #4938: Introduce Onboarding Intro screen (#5385)

<!-- READ ME FIRST: Please fill in the explanation section below and
check off every point from the Essential Checklist! -->
## Explanation
Fix Part of #4938: New
screen to explain to the learner the purpose of the app.

The new learner's name is added as a greeting, passed via the intent.

Tests and placeholder tests have been added to verify that all views are
displayed and navigation works as expected.

## Essential Checklist
<!-- Please tick the relevant boxes by putting an "x" in them. -->
- [x] The PR title and explanation each start with "Fix #bugnum: " (If
this PR fixes part of an issue, prefix the title with "Fix part of
#bugnum: ...".)
- [x] Any changes to
[scripts/assets](https://github.com/oppia/oppia-android/tree/develop/scripts/assets)
files have their rationale included in the PR explanation.
- [x] The PR follows the [style
guide](https://github.com/oppia/oppia-android/wiki/Coding-style-guide).
- [x] The PR does not contain any unnecessary code changes from Android
Studio
([reference](https://github.com/oppia/oppia-android/wiki/Guidance-on-submitting-a-PR#undo-unnecessary-changes)).
- [x] The PR is made from a branch that's **not** called "develop" and
is up-to-date with "develop".
- [x] The PR is **assigned** to the appropriate reviewers
([reference](https://github.com/oppia/oppia-android/wiki/Guidance-on-submitting-a-PR#clarification-regarding-assignees-and-reviewers-section)).

## For UI-specific PRs only
||Portrait|Landscape|
|---|---|---|
|Mobile Light
Mode|![Screenshot_1718117878](https://github.com/oppia/oppia-android/assets/59600948/d01960a0-8eb4-4067-99ac-ccaa2f3b54af)|![Screenshot_1718117885](https://github.com/oppia/oppia-android/assets/59600948/29bb0cae-461e-40f1-930b-d3a2c58e1082)|
|Mobile Dark
Mode|![Screenshot_1718117908](https://github.com/oppia/oppia-android/assets/59600948/5fa43dce-fc9f-4924-ac10-1f1d55865580)|![Screenshot_1718117912](https://github.com/oppia/oppia-android/assets/59600948/e1fc1a9d-e993-4f8f-aa49-970b65dd444b)|
|Tablet Light
Mode|![Screenshot_1718118054](https://github.com/oppia/oppia-android/assets/59600948/4ebd9113-237b-4598-a1b9-982345bff8fd)|![Screenshot_1718118045](https://github.com/oppia/oppia-android/assets/59600948/bf318732-baa2-4f64-aa83-b1f0e82a8ba8)|![Screenshot_1718118119](https://github.com/oppia/oppia-android/assets/59600948/a0628419-867c-405a-b548-f487c1298e76)|
|Tablet Dark
Mode|![Screenshot_1718118119](https://github.com/oppia/oppia-android/assets/59600948/fdd40f9b-7cdf-4878-8833-f4d02500a3c2)|![Screenshot_1718118077](https://github.com/oppia/oppia-android/assets/59600948/3b4112a4-6574-432a-9d85-3a39767385a7)|

app/src/main/AndroidManifest.xml

@@ -344,6 +344,10 @@
       android:name=".app.onboarding.CreateProfileActivity"
       android:label="@string/create_profile_activity_title"
       android:theme="@style/OppiaThemeWithoutActionBar" />
+    <activity
+      android:name=".app.onboarding.IntroActivity"
+      android:label="@string/onboarding_learner_intro_activity_title"
+      android:theme="@style/OppiaThemeWithoutActionBar" />
     <provider
       android:name="androidx.work.impl.WorkManagerInitializer"
       android:authorities="${applicationId}.workmanager-init"

app/src/main/java/org/oppia/android/app/activity/ActivityComponentImpl.kt

@@ -33,6 +33,7 @@ import org.oppia.android.app.home.HomeActivity
 import org.oppia.android.app.home.recentlyplayed.RecentlyPlayedActivity
 import org.oppia.android.app.mydownloads.MyDownloadsActivity
 import org.oppia.android.app.onboarding.CreateProfileActivity
+import org.oppia.android.app.onboarding.IntroActivity
 import org.oppia.android.app.onboarding.OnboardingActivity
 import org.oppia.android.app.onboarding.OnboardingProfileTypeActivity
 import org.oppia.android.app.ongoingtopiclist.OngoingTopicListActivity
@@ -224,4 +225,5 @@ interface ActivityComponentImpl :
   fun inject(classroomListActivity: ClassroomListActivity)
   fun inject(onboardingProfileTypeActivity: OnboardingProfileTypeActivity)
   fun inject(createProfileActivity: CreateProfileActivity)
+  fun inject(introActivity: IntroActivity)
 }

app/src/main/java/org/oppia/android/app/fragment/FragmentComponentImpl.kt

@@ -37,6 +37,7 @@ import org.oppia.android.app.notice.GeneralAvailabilityUpgradeNoticeDialogFragme
 import org.oppia.android.app.notice.OptionalAppDeprecationNoticeDialogFragment
 import org.oppia.android.app.notice.OsDeprecationNoticeDialogFragment
 import org.oppia.android.app.onboarding.CreateProfileFragment
+import org.oppia.android.app.onboarding.IntroFragment
 import org.oppia.android.app.onboarding.OnboardingFragment
 import org.oppia.android.app.onboarding.OnboardingProfileTypeFragment
 import org.oppia.android.app.ongoingtopiclist.OngoingTopicListFragment
@@ -200,4 +201,5 @@ interface FragmentComponentImpl : FragmentComponent, ViewComponentBuilderInjecto
   fun inject(classroomListFragment: ClassroomListFragment)
   fun inject(onboardingProfileTypeFragment: OnboardingProfileTypeFragment)
   fun inject(createProfileFragment: CreateProfileFragment)
+  fun inject(introFragment: IntroFragment)
 }

app/src/main/java/org/oppia/android/app/onboarding/CreateProfileFragmentPresenter.kt

@@ -69,6 +69,11 @@ class CreateProfileFragmentPresenter @Inject constructor(
       val nickname = binding.createProfileNicknameEdittext.text.toString().trim()
 
       createProfileViewModel.hasErrorMessage.set(nickname.isBlank())
+
+      if (createProfileViewModel.hasErrorMessage.get() != true) {
+        val intent = IntroActivity.createIntroActivity(activity, nickname)
+        fragment.startActivity(intent)
+      }
     }
 
     binding.createProfileNicknameEdittext.addTextChangedListener(object : TextWatcher {

app/src/main/java/org/oppia/android/app/onboarding/IntroActivity.kt

@@ -0,0 +1,59 @@
+package org.oppia.android.app.onboarding
+
+import android.content.Context
+import android.content.Intent
+import android.os.Bundle
+import org.oppia.android.app.activity.ActivityComponentImpl
+import org.oppia.android.app.activity.InjectableAutoLocalizedAppCompatActivity
+import org.oppia.android.app.model.IntroActivityParams
+import org.oppia.android.app.model.ScreenName.INTRO_ACTIVITY
+import org.oppia.android.util.extensions.getProtoExtra
+import org.oppia.android.util.extensions.putProtoExtra
+import org.oppia.android.util.logging.CurrentAppScreenNameIntentDecorator.decorateWithScreenName
+import javax.inject.Inject
+
+/** The activity for showing the learner welcome screen. */
+class IntroActivity : InjectableAutoLocalizedAppCompatActivity() {
+  @Inject
+  lateinit var onboardingLearnerIntroActivityPresenter: IntroActivityPresenter
+
+  private lateinit var profileNickname: String
+
+  override fun onCreate(savedInstanceState: Bundle?) {
+    super.onCreate(savedInstanceState)
+    (activityComponent as ActivityComponentImpl).inject(this)
+
+    val params = intent.extractParams()
+    this.profileNickname = params.profileNickname
+
+    onboardingLearnerIntroActivityPresenter.handleOnCreate(profileNickname)
+  }
+
+  companion object {
+    private const val PARAMS_KEY = "OnboardingIntroActivity.params"
+
+    /**
+     * A convenience function for creating a new [OnboardingLearnerIntroActivity] intent by prefilling
+     * common params needed by the activity.
+     */
+    fun createIntroActivity(context: Context, profileNickname: String): Intent {
+      val params = IntroActivityParams.newBuilder()
+        .setProfileNickname(profileNickname)
+        .build()
+      return createOnboardingLearnerIntroActivity(context, params)
+    }
+
+    private fun createOnboardingLearnerIntroActivity(
+      context: Context,
+      params: IntroActivityParams
+    ): Intent {
+      return Intent(context, IntroActivity::class.java).apply {
+        putProtoExtra(PARAMS_KEY, params)
+        decorateWithScreenName(INTRO_ACTIVITY)
+      }
+    }
+
+    private fun Intent.extractParams() =
+      getProtoExtra(PARAMS_KEY, IntroActivityParams.getDefaultInstance())
+  }
+}

app/src/main/java/org/oppia/android/app/onboarding/IntroActivityPresenter.kt

@@ -0,0 +1,49 @@
+package org.oppia.android.app.onboarding
+
+import android.os.Bundle
+import androidx.appcompat.app.AppCompatActivity
+import androidx.databinding.DataBindingUtil
+import org.oppia.android.R
+import org.oppia.android.app.activity.ActivityScope
+import org.oppia.android.databinding.IntroActivityBinding
+import javax.inject.Inject
+
+private const val TAG_LEARNER_INTRO_FRAGMENT = "TAG_INTRO_FRAGMENT"
+
+/** Argument key for bundling the profileId. */
+const val PROFILE_NICKNAME_ARGUMENT_KEY = "profile_nickname"
+
+/** The Presenter for [IntroActivity]. */
+@ActivityScope
+class IntroActivityPresenter @Inject constructor(
+  private val activity: AppCompatActivity
+) {
+  private lateinit var binding: IntroActivityBinding
+
+  /** Handle creation and binding of the [IntroActivity] layout. */
+  fun handleOnCreate(profileNickname: String) {
+    binding = DataBindingUtil.setContentView(activity, R.layout.intro_activity)
+    binding.lifecycleOwner = activity
+
+    if (getIntroFragment() == null) {
+      val introFragment = IntroFragment()
+
+      val args = Bundle()
+      args.putString(PROFILE_NICKNAME_ARGUMENT_KEY, profileNickname)
+      introFragment.arguments = args
+
+      activity.supportFragmentManager.beginTransaction().add(
+        R.id.learner_intro_fragment_placeholder,
+        introFragment,
+        TAG_LEARNER_INTRO_FRAGMENT
+      )
+        .commitNow()
+    }
+  }
+
+  private fun getIntroFragment(): IntroFragment? {
+    return activity.supportFragmentManager.findFragmentByTag(
+      TAG_LEARNER_INTRO_FRAGMENT
+    ) as? IntroFragment
+  }
+}

app/src/main/java/org/oppia/android/app/onboarding/IntroFragment.kt

@@ -0,0 +1,38 @@
+package org.oppia.android.app.onboarding
+
+import android.content.Context
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import org.oppia.android.app.fragment.FragmentComponentImpl
+import org.oppia.android.app.fragment.InjectableFragment
+import org.oppia.android.util.extensions.getStringFromBundle
+import javax.inject.Inject
+
+/** Fragment that contains the introduction message for new learners. */
+class IntroFragment : InjectableFragment() {
+  @Inject
+  lateinit var introFragmentPresenter: IntroFragmentPresenter
+
+  override fun onAttach(context: Context) {
+    super.onAttach(context)
+    (fragmentComponent as FragmentComponentImpl).inject(this)
+  }
+
+  override fun onCreateView(
+    inflater: LayoutInflater,
+    container: ViewGroup?,
+    savedInstanceState: Bundle?
+  ): View? {
+    val profileNickname =
+      checkNotNull(arguments?.getStringFromBundle(PROFILE_NICKNAME_ARGUMENT_KEY)) {
+        "Expected profileNickname to be included in the arguments for IntroFragment."
+      }
+    return introFragmentPresenter.handleCreateView(
+      inflater,
+      container,
+      profileNickname
+    )
+  }
+}

app/src/main/java/org/oppia/android/app/onboarding/IntroFragmentPresenter.kt

@@ -0,0 +1,55 @@
+package org.oppia.android.app.onboarding
+
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.appcompat.app.AppCompatActivity
+import androidx.fragment.app.Fragment
+import org.oppia.android.R
+import org.oppia.android.app.translation.AppLanguageResourceHandler
+import org.oppia.android.databinding.LearnerIntroFragmentBinding
+import javax.inject.Inject
+
+/** The presenter for [IntroFragment]. */
+class IntroFragmentPresenter @Inject constructor(
+  private var fragment: Fragment,
+  private val activity: AppCompatActivity,
+  private val appLanguageResourceHandler: AppLanguageResourceHandler,
+) {
+  private lateinit var binding: LearnerIntroFragmentBinding
+
+  /** Handle creation and binding of the  OnboardingLearnerIntroFragment layout. */
+  fun handleCreateView(
+    inflater: LayoutInflater,
+    container: ViewGroup?,
+    profileNickname: String,
+  ): View {
+    binding = LearnerIntroFragmentBinding.inflate(
+      inflater,
+      container,
+      /* attachToRoot= */ false
+    )
+    binding.lifecycleOwner = fragment
+
+    setLearnerName(profileNickname)
+
+    binding.onboardingNavigationBack.setOnClickListener {
+      activity.finish()
+    }
+
+    binding.onboardingLearnerIntroFeedback.text =
+      appLanguageResourceHandler.getStringInLocaleWithWrapping(
+        R.string.onboarding_learner_intro_feedback_text,
+        appLanguageResourceHandler.getStringInLocale(R.string.app_name)
+      )
+
+    return binding.root
+  }
+
+  private fun setLearnerName(profileName: String) {
+    binding.onboardingLearnerIntroTitle.text =
+      appLanguageResourceHandler.getStringInLocaleWithWrapping(
+        R.string.onboarding_learner_intro_activity_text, profileName
+      )
+  }
+}

app/src/main/res/drawable/ic_green_check.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+  android:width="20dp"
+  android:height="20dp"
+  android:viewportWidth="20"
+  android:viewportHeight="20">
+  <path
+    android:pathData="M0,13.5385C0.1907,13.9557 0.5447,14.2878 0.8361,14.6375C1.32,15.2186 1.7995,15.8019 2.2679,16.396C2.8501,17.1343 3.6537,18.3712 4.1667,19.1616C4.3932,19.5105 4.4232,19.696 4.7823,19.9109C4.9976,20.0397 5.3221,19.9862 5.5614,19.9862H7.3671C7.5963,19.9862 7.9821,20.0594 8.1554,19.8687C8.4929,19.4973 8.6357,18.6971 8.8161,18.2277C9.1803,17.2804 9.6335,16.3627 10.061,15.4435C11.3427,12.6875 12.9254,10.0628 14.5898,7.5304C15.7954,5.696 17.1571,3.8561 18.7724,2.3716C19.2131,1.9667 20.3897,1.2326 19.87,0.5122C19.6045,0.1443 19.0427,0.0956 18.6344,0.0371C17.1884,-0.1701 15.7418,0.5127 14.7342,1.5226C12.207,4.0557 10.39,7.1461 8.5007,10.1681C7.9992,10.9704 7.5674,11.8236 7.1234,12.6593C6.9651,12.9573 6.7927,13.5016 6.485,13.6691C6.2234,13.8114 5.8627,13.6406 5.6337,13.5033C4.9993,13.1227 4.5233,12.5324 4.1086,11.9266C3.9712,11.7258 3.8034,11.3051 3.5324,11.2688C3.2105,11.2257 2.7761,11.6711 2.5279,11.8413C1.698,12.4104 0.8749,13.0444 0,13.5385Z"
+    android:fillColor="#00645C"/>
+</vector>

app/src/main/res/layout-land/learner_intro_fragment.xml

@@ -0,0 +1,96 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:android="http://schemas.android.com/apk/res/android"
+  xmlns:app="http://schemas.android.com/apk/res-auto">
+
+  <androidx.constraintlayout.widget.ConstraintLayout
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:background="@color/component_color_onboarding_learner_intro_background_color">
+
+    <TextView
+      android:id="@+id/onboarding_learner_intro_title"
+      style="@style/OnboardingHeaderStyle"
+      android:layout_marginTop="@dimen/phone_shared_margin_large"
+      android:text="@string/onboarding_learner_intro_activity_text"
+      android:textColor="@color/component_color_onboarding_learner_intro_header_color"
+      app:layout_constraintEnd_toEndOf="parent"
+      app:layout_constraintStart_toStartOf="parent"
+      app:layout_constraintTop_toTopOf="parent" />
+
+    <com.google.android.material.textview.MaterialTextView
+      android:id="@+id/onboarding_learner_intro_classroom"
+      style="@style/OnboardingLearnerIntroBulletsStyle"
+      android:layout_marginTop="@dimen/phone_shared_margin_medium"
+      android:text="@string/onboarding_learner_intro_classroom_text"
+      app:layout_constraintStart_toStartOf="parent"
+      app:layout_constraintEnd_toEndOf="parent"
+      app:layout_constraintWidth_percent="0.7"
+      app:layout_constraintTop_toBottomOf="@id/onboarding_learner_intro_title" />
+
+    <com.google.android.material.textview.MaterialTextView
+      android:id="@+id/onboarding_learner_intro_practice"
+      style="@style/OnboardingLearnerIntroBulletsStyle"
+      android:layout_marginTop="@dimen/phone_shared_margin_small"
+      android:text="@string/onboarding_learner_intro_practice_text"
+      app:layout_constraintStart_toStartOf="@id/onboarding_learner_intro_classroom"
+      app:layout_constraintTop_toBottomOf="@id/onboarding_learner_intro_classroom" />
+
+    <com.google.android.material.textview.MaterialTextView
+      android:id="@+id/onboarding_learner_intro_feedback"
+      style="@style/OnboardingLearnerIntroBulletsStyle"
+      android:layout_marginTop="@dimen/phone_shared_margin_small"
+      android:text="@string/onboarding_learner_intro_feedback_text"
+      app:layout_constraintStart_toStartOf="@id/onboarding_learner_intro_classroom"
+      app:layout_constraintTop_toBottomOf="@id/onboarding_learner_intro_practice" />
+
+    <androidx.constraintlayout.widget.Guideline
+      android:id="@+id/learner_intro_center_guide"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:orientation="horizontal"
+      app:layout_constraintGuide_percent="0.50" />
+
+    <org.oppia.android.app.customview.OppiaCurveBackgroundView
+      android:id="@+id/onboarding_learner_intro_background"
+      android:layout_width="match_parent"
+      android:layout_height="0dp"
+      app:customBackgroundColor="@{@color/component_color_onboarding_shared_white_color}"
+      app:layout_constraintTop_toBottomOf="@id/learner_intro_center_guide" />
+
+    <ImageView
+      android:id="@+id/learner_intro_otter_imageview"
+      android:layout_width="wrap_content"
+      android:layout_height="112dp"
+      android:layout_marginTop="@dimen/phone_shared_margin_xl"
+      android:contentDescription="@string/onboarding_otter_content_description"
+      app:layout_constraintEnd_toStartOf="@id/onboarding_navigation_continue"
+      app:layout_constraintStart_toEndOf="@id/onboarding_navigation_back"
+      app:layout_constraintTop_toBottomOf="@id/learner_intro_center_guide"
+      app:srcCompat="@drawable/otter" />
+
+    <Button
+      android:id="@+id/onboarding_navigation_back"
+      style="@style/OnboardingNavigationSecondaryButton"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:text="@string/onboarding_navigation_back"
+      android:layout_marginStart="@dimen/phone_shared_margin_medium"
+      android:layout_marginBottom="@dimen/phone_shared_margin_medium"
+      app:layout_constraintBottom_toBottomOf="parent"
+      app:layout_constraintEnd_toStartOf="@id/onboarding_navigation_continue"
+      app:layout_constraintHorizontal_chainStyle="spread_inside"
+      app:layout_constraintStart_toStartOf="parent" />
+
+    <Button
+      android:id="@+id/onboarding_navigation_continue"
+      style="@style/OnboardingNavigationPrimaryButton"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:text="@string/onboarding_navigation_continue"
+      app:layout_constraintBottom_toBottomOf="parent"
+      app:layout_constraintEnd_toEndOf="parent"
+      android:layout_marginEnd="@dimen/phone_shared_margin_medium"
+      android:layout_marginBottom="@dimen/phone_shared_margin_medium"
+      app:layout_constraintStart_toEndOf="@id/onboarding_navigation_back" />
+  </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>