Implemented navigation component; deleting an entry now shows a snack bar that allows for undo; edited several layouts

app/src/main/java/com/denizd/textbasic/activity/MainActivity.kt

@@ -1,19 +1,15 @@
 package com.denizd.textbasic.activity
 
-import android.app.backup.BackupManager
 import android.appwidget.AppWidgetManager
 import android.content.ComponentName
 import android.content.Intent
 import android.os.Bundle
 import androidx.appcompat.app.AppCompatActivity
-import androidx.lifecycle.Lifecycle
-import com.denizd.textbasic.R
+import androidx.navigation.fragment.NavHostFragment
+import androidx.navigation.fragment.findNavController
+import androidx.navigation.ui.setupWithNavController
 import com.denizd.textbasic.databinding.ActivityMainBinding
-import com.denizd.textbasic.fragment.GuideFragment
-import com.denizd.textbasic.fragment.QuoteFragment
-import com.denizd.textbasic.fragment.SettingsFragment
 import com.denizd.textbasic.widget.TextCanvasWidget
-import com.google.android.material.snackbar.Snackbar
 
 class MainActivity : AppCompatActivity() {
 
@@ -24,57 +20,9 @@ class MainActivity : AppCompatActivity() {
         binding = ActivityMainBinding.inflate(this.layoutInflater)
         setContentView(binding.root)
 
-        binding.buttonBackupUpload.setOnClickListener {
-            BackupManager(this).dataChanged()
-            Snackbar.make(binding.rootLayout, R.string.snack_backup_upload, Snackbar.LENGTH_LONG).show()
-        }
-
-        binding.bottomNav.setOnItemSelectedListener { item ->
-            loadFragment(item.itemId)
-        }
-    }
-
-    override fun onResume() {
-        super.onResume()
-
-        if (supportFragmentManager.fragments.size == 0) {
-            binding.bottomNav.selectedItemId = R.id.quotes
-            loadFragment(R.id.quotes)
-        }
-    }
-
-    private fun loadFragment(type: Int): Boolean {
-        val fragment = when (type) {
-            R.id.quotes -> QuoteFragment()
-            R.id.guide -> GuideFragment()
-            R.id.settings -> SettingsFragment()
-            else -> QuoteFragment()
-        }//supportFragmentManager.findFragmentByTag(type) ?: viewModel.getFragment(type)
-
-        if (supportFragmentManager.fragments.isNotEmpty() &&
-            supportFragmentManager.fragments[supportFragmentManager.fragments.size-1]
-                .tag?.equals(type.toString()) == true
-        ) {
-            return false
-        }
-
-        if (fragment.lifecycle.currentState != Lifecycle.State.INITIALIZED) {
-            return false
-        }
-
-        supportFragmentManager.beginTransaction()
-            .replace(R.id.fragment_container, fragment, type.toString())
-//            .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE)
-            .commit()
-
-//        with (supportFragmentManager) {
-//            beginTransaction()
-//                .hide(fragments[fragments.size - 1]) // should this be 0?
-//                .show(findFragmentByTag(type) ?: TODO())
-//                .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN)
-//                .commit()
-//        }
-        return true
+        binding.navView.setupWithNavController(
+            binding.navHostFragmentContentMain.getFragment<NavHostFragment>().findNavController()
+        )
     }
 
     override fun onPause() {

app/src/main/java/com/denizd/textbasic/adapter/QuoteAdapter.kt

@@ -5,14 +5,15 @@ import android.text.TextWatcher
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import android.widget.ImageButton
 import android.widget.TextView
 import androidx.recyclerview.widget.RecyclerView
 import com.denizd.textbasic.R
+import com.google.android.material.button.MaterialButton
 import java.util.Collections
 
 class QuoteAdapter(
     quotes: List<String>,
+    private val onDeleteListener: OnDeleteListener,
 ) : RecyclerView.Adapter<QuoteAdapter.QuoteViewHolder>(),
     RecyclerRowMoveCallback.RecyclerViewTouchHelperContract {
 
@@ -20,8 +21,8 @@ class QuoteAdapter(
 
     class QuoteViewHolder(view: View) : RecyclerView.ViewHolder(view) {
 
-        val quote: TextView = view.findViewById(R.id.quote)
-        val delete: ImageButton = view.findViewById(R.id.delete_button)
+        val quote: TextView = view.findViewById(R.id.edit_text_quote)
+        val delete: MaterialButton = view.findViewById(R.id.delete_button)
     }
 
 //    override fun getItemViewType(position: Int): Int {
@@ -47,6 +48,7 @@ class QuoteAdapter(
         })
 
         holder.delete.setOnClickListener {
+            onDeleteListener.onDelete(mutableQuotes[holder.layoutPosition], holder.layoutPosition)
             mutableQuotes.removeAt(holder.layoutPosition)
             notifyItemRemoved(holder.layoutPosition)
         }
@@ -59,6 +61,11 @@ class QuoteAdapter(
         notifyItemInserted(mutableQuotes.size + 1)
     }
 
+    fun addEntryAt(index: Int, entry: String) {
+        mutableQuotes.add(index, entry)
+        notifyItemInserted(index)
+    }
+
     fun getAllQuotes(): Array<String> {
         return mutableQuotes.filter { s -> s.isNotBlank() }.toTypedArray()
     }
@@ -80,4 +87,8 @@ class QuoteAdapter(
     override fun onRowClear(viewHolder: QuoteViewHolder) {
         // TODO
     }
+
+    interface OnDeleteListener {
+        fun onDelete(entry: String, index: Int)
+    }
 }

app/src/main/java/com/denizd/textbasic/fragment/QuoteFragment.kt

@@ -1,6 +1,5 @@
 package com.denizd.textbasic.fragment
 
-import android.animation.LayoutTransition
 import android.os.Bundle
 import android.view.View
 import androidx.recyclerview.widget.ItemTouchHelper
@@ -11,40 +10,40 @@ import com.denizd.textbasic.util.viewBinding
 import com.denizd.textbasic.R
 import com.denizd.textbasic.adapter.RecyclerRowMoveCallback
 import com.denizd.textbasic.databinding.FragmentQuoteBinding
-import com.google.android.material.transition.MaterialSharedAxis
+import com.denizd.textbasic.util.showSnackBar
 
-class QuoteFragment : BaseFragment(R.layout.fragment_quote) {
+class QuoteFragment : BaseFragment(R.layout.fragment_quote), QuoteAdapter.OnDeleteListener {
 
     private lateinit var storage: QuoteStorage
     private lateinit var quoteAdapter: QuoteAdapter
 
     private val binding: FragmentQuoteBinding by viewBinding(FragmentQuoteBinding::bind)
 
-    override fun onCreate(savedInstanceState: Bundle?) {
-        super.onCreate(savedInstanceState)
-
-        exitTransition = MaterialSharedAxis(MaterialSharedAxis.Z, true)
-        reenterTransition = MaterialSharedAxis(MaterialSharedAxis.Z, false)
-
-        enterTransition = MaterialSharedAxis(MaterialSharedAxis.Z, false)
-        returnTransition = MaterialSharedAxis(MaterialSharedAxis.Z, true)
-    }
-
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
 
-        binding.quoteConstraintLayout.layoutTransition.enableTransitionType(LayoutTransition.CHANGING)
-
         storage = QuoteStorage(context)
-        quoteAdapter = QuoteAdapter(storage.getAllQuotes())
+        quoteAdapter = QuoteAdapter(storage.getAllQuotes(), this)
 
-        binding.quoteScroller.let { s ->
-            s.layoutManager = LinearLayoutManager(context)
-            ItemTouchHelper(RecyclerRowMoveCallback(quoteAdapter)).attachToRecyclerView(s)
-            s.adapter = quoteAdapter
+        binding.recyclerView.layoutManager = LinearLayoutManager(context)
+        ItemTouchHelper(RecyclerRowMoveCallback(quoteAdapter))
+            .attachToRecyclerView(binding.recyclerView)
+        binding.recyclerView.adapter = quoteAdapter
+
+        // Set up scroll change listener to shrink and extend FAB accordingly
+        binding.recyclerView.setOnScrollChangeListener { _, _, scrollY, _, oldScrollY ->
+            // Calculate the vertical scroll difference
+            val dy = scrollY - oldScrollY
+            if (dy > 0) {
+                // If scrolling down, shrink the FAB
+                binding.fabAddQuote.shrink()
+            } else if (dy < 0) {
+                // If scrolling up, extend the FAB
+                binding.fabAddQuote.extend()
+            }
         }
 
-        binding.addFab.setOnClickListener {
+        binding.fabAddQuote.setOnClickListener {
             quoteAdapter.addNewQuote()
         }
     }
@@ -57,4 +56,15 @@ class QuoteFragment : BaseFragment(R.layout.fragment_quote) {
         save()
         super.onPause()
     }
+
+    override fun onDelete(entry: String, index: Int) {
+        context.theme.showSnackBar(
+            binding.coordinatorLayout,
+            getString(R.string.quote_fragment_snack_text),
+            null,
+            getString(R.string.quote_fragment_snack_undo),
+        ) {
+            quoteAdapter.addEntryAt(index, entry)
+        }
+    }
 }

app/src/main/java/com/denizd/textbasic/util/Extensions.kt

@@ -0,0 +1,56 @@
+package com.denizd.textbasic.util
+
+import android.content.res.Resources
+import android.util.TypedValue
+import android.view.View
+import androidx.annotation.AttrRes
+import androidx.coordinatorlayout.widget.CoordinatorLayout
+import com.google.android.material.snackbar.Snackbar
+
+/**
+ * Retrieves a specified colour customised to the currently applied theme.
+ *
+ * @param id    attribute ID of the colour reference
+ * @return      resolved colour
+ */
+fun Resources.Theme.getThemedColor(@AttrRes id: Int): Int = TypedValue().also { value ->
+    resolveAttribute(id, value, true)
+}.data
+
+/**
+ * Show a snack bar. Colours will be applied according to the theme given.
+ *
+ * @receiver            theme to apply colours of
+ * @param view          view where the snack bar will be shown in
+ * @param text          text to present in the snack bar
+ * @param anchor        view to anchor the snack bar to
+ * @param actionText    text to show on the action button; button will only be shown if a value is
+ *                      passed here
+ * @param action        action to execute if the action button is pressed
+ */
+fun Resources.Theme.showSnackBar(
+    view: CoordinatorLayout,
+    text: String,
+    anchor: View? = null,
+    actionText: String = "",
+    action: () -> Unit = {},
+) {
+    val s = Snackbar.make(view, text, Snackbar.LENGTH_SHORT)
+        // Set colours
+        .setTextColor(getThemedColor(com.google.android.material.R.attr.colorOnSurfaceInverse))
+        .setBackgroundTint(getThemedColor(com.google.android.material.R.attr.colorSurfaceInverse))
+
+    if (actionText.isNotBlank()) {
+        // Set action, if a value for the text has been passed
+        s.setAction(actionText) {
+            action()
+        }
+
+        // Show this snack bar for a longer time for the user to have a chance to react
+        s.duration = Snackbar.LENGTH_LONG
+    }
+
+    // Set anchor view, if one has been passed
+    anchor?.let { a -> s.setAnchorView(a) }
+    s.show()
+}