Fix oppia#2756: clickable text summary for inactive cards

app/src/main/java/org/oppia/android/app/story/StoryFragmentPresenter.kt

@@ -1,6 +1,12 @@
 package org.oppia.android.app.story
 
 import android.content.res.Resources
+import android.graphics.Typeface
+import android.text.SpannableString
+import android.text.Spanned
+import android.text.TextPaint
+import android.text.method.LinkMovementMethod
+import android.text.style.ClickableSpan
 import android.util.DisplayMetrics
 import android.util.TypedValue
 import android.view.LayoutInflater
@@ -12,7 +18,9 @@ import androidx.fragment.app.Fragment
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.LinearSmoothScroller
 import androidx.recyclerview.widget.RecyclerView
+import org.oppia.android.R
 import org.oppia.android.app.home.RouteToExplorationListener
+import org.oppia.android.app.model.ChapterPlayState
 import org.oppia.android.app.model.EventLog
 import org.oppia.android.app.recyclerview.BindableAdapter
 import org.oppia.android.app.story.storyitemviewmodel.StoryChapterSummaryViewModel
@@ -142,6 +150,35 @@ class StoryFragmentPresenter @Inject constructor(
             ).parseOppiaHtml(
               storyItemViewModel.summary, binding.chapterSummary
             )
+          if (storyItemViewModel.chapterSummary.chapterPlayState
+            == ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES
+          ) {
+            val missingPrerequisiteSummary = fragment.getString(
+              R.string.chapter_prerequisite_title_label,
+              storyItemViewModel.index.toString(),
+              storyItemViewModel.missingPrerequisiteChapter.name
+            )
+            val chapterLockedSpannable = SpannableString(missingPrerequisiteSummary)
+            val clickableSpan = object : ClickableSpan() {
+              override fun onClick(widget: View) {
+                smoothScrollToPosition(storyItemViewModel.index - 1)
+              }
+
+              override fun updateDrawState(ds: TextPaint) {
+                super.updateDrawState(ds)
+                ds.isUnderlineText = false
+                ds.typeface = Typeface.DEFAULT_BOLD
+              }
+            }
+            chapterLockedSpannable.setSpan(
+              clickableSpan,
+              9,
+              chapterLockedSpannable.length - 24,
+              Spanned.SPAN_EXCLUSIVE_EXCLUSIVE
+            )
+            binding.htmlContent = chapterLockedSpannable
+            binding.chapterSummary.movementMethod = LinkMovementMethod.getInstance()
+          }
         }
       )
       .build()

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

@@ -76,8 +76,9 @@
             android:layout_marginEnd="8dp"
             android:layout_marginBottom="4dp"
             android:fontFamily="sans-serif"
-            android:text="@{viewModel.chapterSummary.chapterPlayState != ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES ? htmlContent : @string/chapter_prerequisite_title_label(viewModel.index, viewModel.missingPrerequisiteChapter.name)}"
+            android:text="@{htmlContent}"
             android:textColor="@color/oppiaPrimaryText"
+            android:textColorLink="@color/colorPrimary"
             android:textSize="16sp"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintEnd_toEndOf="parent"

app/src/main/res/layout-sw600dp/story_chapter_view.xml

@@ -112,8 +112,9 @@
             android:layout_marginEnd="8dp"
             android:layout_marginBottom="4dp"
             android:fontFamily="sans-serif"
-            android:text="@{viewModel.chapterSummary.chapterPlayState != ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES ? htmlContent : @string/chapter_prerequisite_title_label(viewModel.index, viewModel.missingPrerequisiteChapter.name)}"
+            android:text="@{htmlContent}"
             android:textColor="@color/oppiaPrimaryText"
+            android:textColorLink="@color/colorPrimary"
             android:textSize="16sp"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintEnd_toEndOf="parent"

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

@@ -112,8 +112,9 @@
             android:layout_marginEnd="8dp"
             android:layout_marginBottom="4dp"
             android:fontFamily="sans-serif"
-            android:text="@{viewModel.chapterSummary.chapterPlayState != ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES ? htmlContent : @string/chapter_prerequisite_title_label(viewModel.index, viewModel.missingPrerequisiteChapter.name)}"
+            android:text="@{htmlContent}"
             android:textColor="@color/oppiaPrimaryText"
+            android:textColorLink="@color/colorPrimary"
             android:textSize="16sp"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintEnd_toEndOf="parent"

app/src/sharedTest/java/org/oppia/android/app/story/StoryFragmentTest.kt

@@ -4,17 +4,25 @@ import android.app.Application
 import android.content.Context
 import android.content.Intent
 import android.content.res.Resources
+import android.text.SpannableString
+import android.text.style.ClickableSpan
+import android.view.View
+import android.widget.TextView
 import androidx.appcompat.app.AppCompatActivity
 import androidx.recyclerview.widget.RecyclerView
 import androidx.test.core.app.ActivityScenario.launch
 import androidx.test.core.app.ApplicationProvider
 import androidx.test.espresso.Espresso.onView
+import androidx.test.espresso.NoMatchingViewException
+import androidx.test.espresso.UiController
+import androidx.test.espresso.ViewAction
 import androidx.test.espresso.action.ViewActions.click
 import androidx.test.espresso.assertion.ViewAssertions.matches
 import androidx.test.espresso.contrib.RecyclerViewActions.scrollToPosition
 import androidx.test.espresso.intent.Intents
 import androidx.test.espresso.intent.Intents.intended
 import androidx.test.espresso.intent.matcher.IntentMatchers.hasComponent
+import androidx.test.espresso.matcher.ViewMatchers.isDisplayed
 import androidx.test.espresso.matcher.ViewMatchers.isRoot
 import androidx.test.espresso.matcher.ViewMatchers.withContentDescription
 import androidx.test.espresso.matcher.ViewMatchers.withId
@@ -26,6 +34,7 @@ import dagger.Component
 import dagger.Module
 import dagger.Provides
 import org.hamcrest.CoreMatchers.allOf
+import org.hamcrest.Matchers
 import org.junit.After
 import org.junit.Before
 import org.junit.Rule
@@ -51,6 +60,7 @@ import org.oppia.android.app.customview.LessonThumbnailImageView
 import org.oppia.android.app.model.ProfileId
 import org.oppia.android.app.player.exploration.ExplorationActivity
 import org.oppia.android.app.player.state.hintsandsolution.HintsAndSolutionConfigModule
+import org.oppia.android.app.recyclerview.RecyclerViewMatcher.Companion.atPosition
 import org.oppia.android.app.recyclerview.RecyclerViewMatcher.Companion.atPositionOnView
 import org.oppia.android.app.recyclerview.RecyclerViewMatcher.Companion.hasItemCount
 import org.oppia.android.app.shim.ViewBindingShimModule
@@ -359,10 +369,9 @@ class StoryFragmentTest {
   }
 
   @Test
-  fun testStoryFragment_configChange_chapterMissingPrerequisiteThumbnailIsBlurred() {
+  fun testStoryFragment_chapterMissingPrerequisiteIsShownCorrectly() {
     launch<StoryActivity>(createFractionsStoryActivityIntent()).use {
       testCoroutineDispatchers.runCurrent()
-      onView(isRoot()).perform(orientationLandscape())
       onView(allOf(withId(R.id.story_chapter_list))).perform(
         scrollToPosition<RecyclerView.ViewHolder>(
           2
@@ -372,26 +381,21 @@ class StoryFragmentTest {
         atPositionOnView(
           recyclerViewId = R.id.story_chapter_list,
           position = 2,
-          targetViewId = R.id.chapter_thumbnail
-        )
-      ).check { view, noViewFoundException ->
-        var lessonThumbnailImageView = view.findViewById<LessonThumbnailImageView>(
-          R.id.chapter_thumbnail
+          targetViewId = R.id.chapter_summary
         )
-        verify(lessonThumbnailImageView.imageLoader, atLeastOnce()).loadDrawable(
-          imageDrawableResId = anyInt(),
-          target = anyOrNull(),
-          transformations = capture(listCaptor)
+      ).check(
+        matches(
+          withText("Complete Chapter 1: What is a Fraction? to unlock this chapter.")
         )
-        assertThat(listCaptor.value).contains(ImageTransformation.BLUR)
-      }
+      )
     }
   }
 
   @Test
-  fun testStoryFragment_chapterMissingPrerequisiteIsShownCorrectly() {
+  fun testStoryFragment_changeConfiguration_chapterMissingPrerequisiteIsShownCorrectly() {
     launch<StoryActivity>(createFractionsStoryActivityIntent()).use {
       testCoroutineDispatchers.runCurrent()
+      onView(isRoot()).perform(orientationLandscape())
       onView(allOf(withId(R.id.story_chapter_list))).perform(
         scrollToPosition<RecyclerView.ViewHolder>(
           2
@@ -412,7 +416,40 @@ class StoryFragmentTest {
   }
 
   @Test
-  fun testStoryFragment_changeConfiguration_chapterMissingPrerequisiteIsShownCorrectly() {
+  fun testStoryFragment_clickPrerequisiteChapter_prerequisiteChapterCardIsDisplayed() {
+    launch<StoryActivity>(createFractionsStoryActivityIntent()).use {
+      testCoroutineDispatchers.runCurrent()
+      onView(allOf(withId(R.id.story_chapter_list))).perform(
+        scrollToPosition<RecyclerView.ViewHolder>(
+          2
+        )
+      )
+      onView(
+        atPositionOnView(
+          recyclerViewId = R.id.story_chapter_list,
+          position = 2,
+          targetViewId = R.id.chapter_summary
+        )
+      ).perform(
+        clickClickableSpan(
+          "Complete Chapter 1: What is a Fraction? to unlock this chapter."
+        )
+      )
+      onView(
+        atPosition(
+          recyclerViewId = R.id.story_chapter_list,
+          position = 1
+        )
+      ).check(
+        matches(
+          isDisplayed()
+        )
+      )
+    }
+  }
+
+  @Test
+  fun testStoryFragment_configChange_clickPrerequisiteChapter_prerequisiteChapterCardIsDisplayed() {
     launch<StoryActivity>(createFractionsStoryActivityIntent()).use {
       testCoroutineDispatchers.runCurrent()
       onView(isRoot()).perform(orientationLandscape())
@@ -427,9 +464,19 @@ class StoryFragmentTest {
           position = 2,
           targetViewId = R.id.chapter_summary
         )
+      ).perform(
+        clickClickableSpan(
+          "Complete Chapter 1: What is a Fraction? to unlock this chapter."
+        )
+      )
+      onView(
+        atPosition(
+          recyclerViewId = R.id.story_chapter_list,
+          position = 1
+        )
       ).check(
         matches(
-          withText("Complete Chapter 1: What is a Fraction? to unlock this chapter.")
+          isDisplayed()
         )
       )
     }
@@ -489,6 +536,59 @@ class StoryFragmentTest {
     }
   }
 
+  /**
+   * Reference:
+   * https://stackoverflow.com/questions/38314077/how-to-click-a-clickablespan-using-espresso
+   */
+  private fun clickClickableSpan(textToClick: CharSequence): ViewAction {
+    return object : ViewAction {
+
+      override fun getConstraints(): org.hamcrest.Matcher<View> {
+        return Matchers.instanceOf(TextView::class.java)
+      }
+
+      override fun getDescription(): String {
+        return "clicking on a ClickableSpan"
+      }
+
+      override fun perform(uiController: UiController, view: View) {
+        val textView = view as TextView
+        val spannableString = textView.text as SpannableString
+        if (spannableString.isEmpty()) {
+          // TextView is empty, nothing to do
+          throw NoMatchingViewException.Builder()
+            .includeViewHierarchy(true)
+            .withRootView(textView)
+            .build()
+        }
+        // Get the links inside the TextView and check if we find textToClick
+        val spans = spannableString.getSpans(
+          0,
+          spannableString.length,
+          ClickableSpan::class.java
+        )
+        if (spans.isNotEmpty()) {
+          var spanCandidate: ClickableSpan
+          for (span: ClickableSpan in spans) {
+            spanCandidate = span
+            val start = spannableString.getSpanStart(spanCandidate)
+            val end = spannableString.getSpanEnd(spanCandidate)
+            val sequence = spannableString.subSequence(start, end)
+            if (textToClick.toString().contains(sequence.toString())) {
+              span.onClick(textView)
+              return
+            }
+          }
+        }
+        // textToClick not found in TextView
+        throw NoMatchingViewException.Builder()
+          .includeViewHierarchy(true)
+          .withRootView(textView)
+          .build()
+      }
+    }
+  }
+
   private fun createFractionsStoryActivityIntent(): Intent {
     return StoryActivity.createStoryActivityIntent(
       ApplicationProvider.getApplicationContext(),