Add Chapters query

Author: lorensr

app/src/main/graphql/guide/graphql/toc/Chapters.graphql

@@ -0,0 +1,7 @@
+query Chapters {
+  chapters {
+    id
+    number
+    title
+  }
+}

app/src/main/java/guide/graphql/toc/data/Apollo.kt

@@ -0,0 +1,11 @@
+package guide.graphql.toc.data
+
+import com.apollographql.apollo.ApolloClient
+
+object Apollo {
+    val client: ApolloClient by lazy {
+        ApolloClient.builder()
+            .serverUrl("https://api.graphql.guide/graphql")
+            .build()
+    }
+}

app/src/main/java/guide/graphql/toc/ui/chapters/ChaptersAdapter.kt

@@ -2,19 +2,22 @@ package guide.graphql.toc.ui.chapters
 
 import android.content.Context
 import android.view.LayoutInflater
+import android.view.View
 import android.view.ViewGroup
 import androidx.recyclerview.widget.RecyclerView
+import guide.graphql.toc.ChaptersQuery
+import guide.graphql.toc.R
 import guide.graphql.toc.databinding.ChapterBinding
 
 class ChaptersAdapter(
     private val context: Context,
-    private var chapters: List<String> = listOf(),
-    private val onItemClicked: ((String) -> Unit)
+    private var chapters: List<ChaptersQuery.Chapter> = listOf(),
+    private val onItemClicked: ((ChaptersQuery.Chapter) -> Unit)
 ) : RecyclerView.Adapter<ChaptersAdapter.ViewHolder>() {
 
     class ViewHolder(val binding: ChapterBinding) : RecyclerView.ViewHolder(binding.root)
 
-    fun updateChapters(chapters: List<String>) {
+    fun updateChapters(chapters: List<ChaptersQuery.Chapter>) {
         this.chapters = chapters
         notifyDataSetChanged()
     }
@@ -30,8 +33,20 @@ class ChaptersAdapter(
 
     override fun onBindViewHolder(holder: ViewHolder, position: Int) {
         val chapter = chapters[position]
-
-        holder.binding.chapterHeader.text = chapter
+        val header =
+            if (chapter.number == null) chapter.title else context.getString(
+                R.string.chapter_number,
+                chapter.number.toInt().toString()
+            )
+
+        holder.binding.chapterHeader.text = header
+        if (chapter.number == null) {
+            holder.binding.chapterSubheader.visibility = View.GONE
+
+        } else {
+            holder.binding.chapterSubheader.text = chapter.title
+            holder.binding.chapterSubheader.visibility = View.VISIBLE
+        }
 
         holder.binding.root.setOnClickListener {
             onItemClicked.invoke(chapter)

app/src/main/java/guide/graphql/toc/ui/chapters/ChaptersFragment.kt

@@ -6,11 +6,16 @@ import android.view.View
 import android.view.ViewGroup
 import android.widget.Toast
 import androidx.fragment.app.Fragment
+import androidx.lifecycle.lifecycleScope
 import androidx.navigation.fragment.findNavController
 import androidx.recyclerview.widget.DividerItemDecoration
 import androidx.recyclerview.widget.LinearLayoutManager
+import com.apollographql.apollo.coroutines.toDeferred
+import com.apollographql.apollo.exception.ApolloException
 import com.google.android.material.transition.MaterialSharedAxis
+import guide.graphql.toc.ChaptersQuery
 import guide.graphql.toc.R
+import guide.graphql.toc.data.Apollo
 import guide.graphql.toc.databinding.ChaptersFragmentBinding
 
 class ChaptersFragment : Fragment() {
@@ -45,25 +50,42 @@ class ChaptersFragment : Fragment() {
             ) { chapter ->
                 findNavController().navigate(
                     ChaptersFragmentDirections.viewSections(
-                        chapterId = 10,
-                        chapterNumber = 10,
-                        chapterTitle = getString(
+                        chapterId = chapter.id,
+                        chapterNumber = chapter.number?.toInt() ?: -1,
+                        chapterTitle = if (chapter.number == null) chapter.title else getString(
                             R.string.chapter_title,
-                            "10",
-                            "Android Dev"
+                            chapter.number.toInt().toString(),
+                            chapter.title
                         )
                     )
                 )
             }
 
         val layoutManager = LinearLayoutManager(requireContext())
         binding.chapters.layoutManager = layoutManager
-
+ 
         val itemDivider = DividerItemDecoration(requireContext(), layoutManager.orientation)
         binding.chapters.addItemDecoration(itemDivider)
         binding.chapters.adapter = adapter
 
-        adapter.updateChapters(listOf("Android Dev"))
+        lifecycleScope.launchWhenStarted {
+            try {
+                val response = Apollo.client.query(
+                    ChaptersQuery()
+                ).toDeferred().await()
+
+                if (response.hasErrors()) {
+                    throw Exception(response.errors?.get(0)?.message)
+                }
+
+                val chapters = response.data?.chapters ?: throw Exception("Data is null")
+                adapter.updateChapters(chapters)
+            } catch (e: ApolloException) {
+                showErrorMessage("GraphQL request failed")
+            } catch (e: Exception) {
+                showErrorMessage(e.message.orEmpty())
+            }
+        }
     }
 
     override fun onDestroyView() {