Transitioned from a fairly custom solution to using a colour palette generated by the Material Theme Builder to simplify colour management. Also began work on a bottom sheet for displaying allergens and additives in canteen offers.

app/src/main/java/com/denizk0461/studip/fragment/AppFragment.kt

@@ -0,0 +1,21 @@
+package com.denizk0461.studip.fragment
+
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.FragmentActivity
+import com.denizk0461.studip.sheet.AppSheet
+
+/**
+ * Fragment super class providing common functionality. Fragments are used for providing the user
+ * with different views and functionality. All fragments should inherit from this.
+ */
+open class AppFragment : Fragment() {
+
+    /**
+     * Opens a bottom sheet. Sheet must be a subclass of [com.denizk0461.studip.sheet.AppSheet].
+     *
+     * @param sheet element that will be displayed
+     */
+    protected fun openBottomSheet(sheet: AppSheet) {
+        sheet.show((context as FragmentActivity).supportFragmentManager, sheet.javaClass.simpleName)
+    }
+}

app/src/main/java/com/denizk0461/studip/fragment/CanteenFragment.kt

@@ -5,11 +5,12 @@ import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import androidx.fragment.app.Fragment
 import androidx.fragment.app.viewModels
+import com.denizk0461.studip.adapter.CanteenOfferItemAdapter
 import com.denizk0461.studip.adapter.CanteenOfferPageAdapter
 import com.denizk0461.studip.databinding.FragmentCanteenBinding
 import com.denizk0461.studip.model.*
+import com.denizk0461.studip.sheet.AllergenSheet
 import com.denizk0461.studip.viewmodel.CanteenViewModel
 import com.google.android.material.tabs.TabLayoutMediator
 
@@ -17,7 +18,7 @@ import com.google.android.material.tabs.TabLayoutMediator
  * User-facing fragment view that displays the canteen offers from the website of the
  * Studierendenwerk Bremen.
  */
-class CanteenFragment : Fragment() {
+class CanteenFragment : AppFragment(), CanteenOfferItemAdapter.OnClickListener {
 
     // Nullable view binding reference
     private var _binding: FragmentCanteenBinding? = null
@@ -91,7 +92,7 @@ class CanteenFragment : Fragment() {
         }
 
         // Set up the view pager's adapter
-        viewPagerAdapter = CanteenOfferPageAdapter(listOf(), 0)
+        viewPagerAdapter = CanteenOfferPageAdapter(listOf(), 0, this)
 
         // Assign the adapter to the view pager
         binding.viewPager.adapter = viewPagerAdapter
@@ -268,4 +269,23 @@ class CanteenFragment : Fragment() {
             )
         }
     }
+
+    /**
+     * Executed when an item has been clicked.
+     *
+     * @param offer item that has been clicked
+     */
+    override fun onClick(offer: CanteenOfferGroupElement) {
+        openBottomSheet(AllergenSheet(offer))
+    }
+
+    /**
+     * Executed when an item has been long-pressed.
+     *
+     * @param offer item that has been long-pressed
+     * @return      whether the long press was successful
+     */
+    override fun onLongClick(offer: CanteenOfferGroupElement): Boolean {
+        return false
+    }
 }

app/src/main/java/com/denizk0461/studip/fragment/EventFragment.kt

@@ -1,7 +1,6 @@
 package com.denizk0461.studip.fragment
 
 import android.os.Bundle
-import androidx.fragment.app.Fragment
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -18,7 +17,7 @@ import java.util.*
 /**
  * User-facing fragment view that displays the user's Stud.IP schedule.
  */
-class EventFragment : Fragment() {
+class EventFragment : AppFragment() {
 
     // Nullable view binding reference
     private var _binding: FragmentEventBinding? = null

app/src/main/java/com/denizk0461/studip/fragment/SettingsFragment.kt

@@ -7,7 +7,6 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import androidx.fragment.app.Fragment
 import com.denizk0461.studip.BuildConfig
 import com.denizk0461.studip.activity.FetcherActivity
 import com.denizk0461.studip.databinding.FragmentSettingsBinding
@@ -15,7 +14,7 @@ import com.denizk0461.studip.databinding.FragmentSettingsBinding
 /**
  * User-facing fragment view that is used to change app settings.
  */
-class SettingsFragment : Fragment() {
+class SettingsFragment : AppFragment() {
 
     // Nullable view binding reference
     private var _binding: FragmentSettingsBinding? = null