footerの実装

app/src/main/java/com/example/kanazawaapp_2019/ShoppingListActivity.kt

@@ -1,7 +1,9 @@
 package com.example.kanazawaapp_2019
 
+import android.content.Intent
 import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
+import com.google.android.material.tabs.TabLayout
 import android.widget.ListView
 import kotlinx.android.synthetic.main.activity_shoppinglist.*
 
@@ -31,7 +33,38 @@ class ShoppingListActivity : AppCompatActivity(), FragmentCallInterface{
 //            val intent = Intent(application, FoodAdditionActivity::class.java)
             startActivity(intent)
         }
+        //footerの実装
+        shoppingListTabLayout.addOnTabSelectedListener(object: TabLayout.OnTabSelectedListener {
+            override fun onTabSelected(tab: TabLayout.Tab) {
+                var position = shoppingListTabLayout.selectedTabPosition
+                when (position) {
+                    0 -> {
+                        val intent = Intent(application, PreservedFoodListActivity::class.java)
+                        startActivities(arrayOf(intent))
+                        overridePendingTransition(R.anim.slide_in_left, R.anim.slide_out_right)
+                    }
+                    else -> {
+                        shoppingListView.setSelection(0)
+                    }
+                }
+            }
 
+            override fun onTabUnselected(tab: TabLayout.Tab) {}
+
+            override fun onTabReselected(tab: TabLayout.Tab) {
+                var position = shoppingListTabLayout.selectedTabPosition
+                when (position) {
+                    0 -> {
+                        val intent = Intent(application, PreservedFoodListActivity::class.java)
+                        startActivities(arrayOf(intent))
+                        overridePendingTransition(R.anim.slide_in_left, R.anim.slide_out_right)
+                    }
+                    else -> {
+                    shoppingListView.setSelection(0)
+                    }
+                }
+            }
+        })
         //listにテストデータを追加
         ListView = findViewById(R.id.shoppingListView)