Fixed the application was crashing when we frequently searching and clicking on any article.

* Added test cases for testing this scenario.

app/src/androidTest/java/org/kiwix/kiwixmobile/search/SearchFragmentTest.kt

@@ -166,6 +166,23 @@ class SearchFragmentTest : BaseActivityTest() {
       // go to reader screen
       pressBack()
     }
+
+    // Added test for checking the crash scenario where the application was crashing when we
+    // frequently searched for article, and clicked on the searched item.
+    search {
+      // test by searching 10 article and clicking on them
+      searchAndClickOnArticle(searchQueryForDownloadedZimFile)
+      searchAndClickOnArticle("A Song")
+      searchAndClickOnArticle("The Ra")
+      searchAndClickOnArticle("The Ge")
+      searchAndClickOnArticle("Wish")
+      searchAndClickOnArticle("WIFI")
+      searchAndClickOnArticle("Woman")
+      searchAndClickOnArticle("Big Ba")
+      searchAndClickOnArticle("My Wor")
+      searchAndClickOnArticle("100")
+      assertArticleLoaded()
+    }
     removeTemporaryZimFilesToFreeUpDeviceStorage()
     LeakAssertions.assertNoLeaks()
   }

app/src/androidTest/java/org/kiwix/kiwixmobile/search/SearchRobot.kt

@@ -20,26 +20,27 @@ package org.kiwix.kiwixmobile.search
 
 import android.view.KeyEvent
 import androidx.recyclerview.widget.RecyclerView
-import androidx.recyclerview.widget.RecyclerView.ViewHolder
 import androidx.test.espresso.Espresso.onView
 import androidx.test.espresso.action.ViewActions.clearText
 import androidx.test.espresso.action.ViewActions.click
 import androidx.test.espresso.action.ViewActions.typeText
 import androidx.test.espresso.assertion.ViewAssertions.matches
 import androidx.test.espresso.contrib.RecyclerViewActions.actionOnItemAtPosition
-import androidx.test.espresso.contrib.RecyclerViewActions.scrollToPosition
-import androidx.test.espresso.matcher.ViewMatchers.isDescendantOfA
-import androidx.test.espresso.matcher.ViewMatchers.isDisplayed
+import androidx.test.espresso.matcher.ViewMatchers.hasDescendant
 import androidx.test.espresso.matcher.ViewMatchers.withId
 import androidx.test.espresso.matcher.ViewMatchers.withText
+import androidx.test.espresso.web.sugar.Web.onWebView
+import androidx.test.espresso.web.webdriver.DriverAtoms.findElement
+import androidx.test.espresso.web.webdriver.Locator
 import androidx.test.uiautomator.UiDevice
 import applyWithViewHierarchyPrinting
 import com.adevinta.android.barista.interaction.BaristaSleepInteractions
-import org.hamcrest.Matchers.allOf
+import com.adevinta.android.barista.internal.matcher.HelperMatchers.atPosition
 import org.kiwix.kiwixmobile.BaseRobot
 import org.kiwix.kiwixmobile.Findable.ViewId
 import org.kiwix.kiwixmobile.core.R
 import org.kiwix.kiwixmobile.testutils.TestUtils
+import org.kiwix.kiwixmobile.testutils.TestUtils.testFlakyView
 
 fun search(func: SearchRobot.() -> Unit) = SearchRobot().applyWithViewHierarchyPrinting(func)
 
@@ -67,6 +68,7 @@ class SearchRobot : BaseRobot() {
   }
 
   fun searchWithFrequentlyTypedWords(query: String, wait: Long = 0L) {
+    testFlakyView({
       val searchView = onView(withId(R.id.search_src_text))
       for (char in query) {
         searchView.perform(typeText(char.toString()))
@@ -74,22 +76,16 @@ class SearchRobot : BaseRobot() {
           BaristaSleepInteractions.sleep(wait)
         }
       }
+    })
   }
 
   fun assertSearchSuccessful(searchResult: String) {
     BaristaSleepInteractions.sleep(TestUtils.TEST_PAUSE_MS_FOR_SEARCH_TEST.toLong())
     val recyclerViewId = R.id.search_list
 
-    // Scroll to the first position in the RecyclerView
-    onView(withId(recyclerViewId)).perform(scrollToPosition<ViewHolder>(0))
-
-    // Match the view at the first position in the RecyclerView
-    onView(withText(searchResult)).check(
+    onView(withId(recyclerViewId)).check(
       matches(
-        allOf(
-          isDisplayed(),
-          isDescendantOfA(withId(recyclerViewId))
-        )
+        atPosition(0, hasDescendant(withText(searchResult)))
       )
     )
   }
@@ -106,4 +102,26 @@ class SearchRobot : BaseRobot() {
     val searchView = onView(withId(R.id.search_src_text))
     searchView.perform(clearText())
   }
+
+  private fun openSearchScreen() {
+    testFlakyView({ onView(withId(R.id.menu_search)).perform(click()) })
+  }
+
+  fun searchAndClickOnArticle(searchString: String) {
+    openSearchScreen()
+    searchWithFrequentlyTypedWords(searchString)
+    clickOnSearchItemInSearchList()
+  }
+
+  fun assertArticleLoaded() {
+    testFlakyView({
+      onWebView()
+        .withElement(
+          findElement(
+            Locator.XPATH,
+            "//*[contains(text(), 'Big Baby DRAM')]"
+          )
+        )
+    })
+  }
 }

core/src/main/java/org/kiwix/kiwixmobile/core/search/SearchFragment.kt

@@ -285,6 +285,15 @@ class SearchFragment : BaseFragment() {
     }
 
   private suspend fun render(state: SearchState) {
+    // Check if the fragment is visible on the screen. This method called multiple times
+    // (7-14 times) when an item in the search list is clicked, which leads to unnecessary
+    // data loading and also causes a crash.
+    // The issue arises because the searchViewModel takes a moment to detach from the window,
+    // and during this time, this method is called multiple times due to the rendering process.
+    // To avoid unnecessary data loading and prevent crashes, we check if the search screen is
+    // visible to the user before proceeding. If the screen is not visible,
+    // we skip the data loading process.
+    // if (!isVisible) return
     searchMutex.withLock {
       // `cancelAndJoin` cancels the previous running job and waits for it to completely cancel.
       renderingJob?.cancelAndJoin()