Added back button for logon and register

app/src/main/java/com/example/mampfmobil/MainActivity.java

 package com.example.mampfmobil;
 
+import android.content.Intent;
 import android.os.Bundle;
 import android.view.View;
 
@@ -31,4 +32,11 @@ public class MainActivity extends AppCompatActivity {
 
     }
 
+    @Override
+    public boolean onSupportNavigateUp() {
+        Intent intent = new Intent(this, MainActivity.class);
+        startActivity(intent);
+        return true; // true zurückgeben, um anzugeben, dass die Aktion behandelt wurde
+    }
+
 }
\ No newline at end of file

app/src/main/java/com/example/mampfmobil/ui/customer/CustomerLogonFragment.java

 package com.example.mampfmobil.ui.customer;
 
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentTransaction;
 import androidx.lifecycle.ViewModelProvider;
@@ -40,6 +42,13 @@ public class CustomerLogonFragment extends Fragment {
         EditText lastname = rootView.findViewById(R.id.editTextLastName);
         Button button = rootView.findViewById(R.id.buttonRegister);
 
+        AppCompatActivity activity = (AppCompatActivity) requireActivity();
+        // Enable the back button in the ActionBar
+        ActionBar actionBar = activity.getSupportActionBar();
+        if(actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+        }
+
         button.setOnClickListener(new View.OnClickListener() {
             private Toast toast; //
             @Override

app/src/main/java/com/example/mampfmobil/ui/customer/CustomerOrdersFragment.java

@@ -60,6 +60,18 @@ public class CustomerOrdersFragment extends Fragment {
         return rootView;
     }
 
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        if (item.getItemId() == android.R.id.home) {
+            // Hier kannst du den gewünschten Code ausführen, wenn der Zurück-Button gedrückt wird
+            // Zum Beispiel:
+            getActivity().onBackPressed(); // Rückwärtsnavigation durchführen
+            return true;
+        }
+        return super.onOptionsItemSelected(item);
+    }
+
     @Override
     public void onActivityCreated(@Nullable Bundle savedInstanceState) {
         super.onActivityCreated(savedInstanceState);

app/src/main/java/com/example/mampfmobil/ui/customer/CustomerRegisterFragment.java

 package com.example.mampfmobil.ui.customer;
 
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.lifecycle.ViewModelProvider;
 
 import android.content.Intent;
@@ -39,6 +41,13 @@ public class CustomerRegisterFragment extends Fragment {
         EditText lastname = rootView.findViewById(R.id.editTextLastName);
         EditText register = rootView.findViewById(R.id.editTextAddress);
 
+        AppCompatActivity activity = (AppCompatActivity) requireActivity();
+        // Enable the back button in the ActionBar
+        ActionBar actionBar = activity.getSupportActionBar();
+        if(actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+        }
+
 
         button.setOnClickListener(new View.OnClickListener() {
             private Toast toast; //

app/src/main/java/com/example/mampfmobil/ui/deliverer/DelivererLogonFragment.java

 package com.example.mampfmobil.ui.deliverer;
 
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentTransaction;
 import androidx.lifecycle.ViewModelProvider;
@@ -42,6 +44,12 @@ public class DelivererLogonFragment extends Fragment {
         EditText firstname = rootView.findViewById(R.id.editTextFirstName);
         EditText lastname = rootView.findViewById(R.id.editTextLastName);
 
+        AppCompatActivity activity = (AppCompatActivity) requireActivity();
+        // Enable the back button in the ActionBar
+        ActionBar actionBar = activity.getSupportActionBar();
+        if(actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+        }
 
         button.setOnClickListener(new View.OnClickListener() {
             private Toast toast; //

app/src/main/java/com/example/mampfmobil/ui/deliverer/DelivererRegisterFragment.java

 package com.example.mampfmobil.ui.deliverer;
 
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.lifecycle.ViewModelProvider;
 
 import android.content.Intent;
@@ -38,6 +40,13 @@ public class DelivererRegisterFragment extends Fragment {
         EditText lastname = rootView.findViewById(R.id.editTextLastName);
         EditText register = rootView.findViewById(R.id.editTextAddress);
 
+        AppCompatActivity activity = (AppCompatActivity) requireActivity();
+        // Enable the back button in the ActionBar
+        ActionBar actionBar = activity.getSupportActionBar();
+        if(actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+        }
+
         button.setOnClickListener(new View.OnClickListener() {
             private Toast toast; //
             @Override

app/src/main/java/com/example/mampfmobil/ui/supplier/SupplierLogonFragment.java

 package com.example.mampfmobil.ui.supplier;
 
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentTransaction;
 import androidx.lifecycle.ViewModelProvider;
@@ -41,6 +43,14 @@ public class SupplierLogonFragment extends Fragment {
         Button button = rootView.findViewById(R.id.buttonRegister);
         EditText firstname = rootView.findViewById(R.id.editTextFirstName);
 
+        AppCompatActivity activity = (AppCompatActivity) requireActivity();
+        // Enable the back button in the ActionBar
+        ActionBar actionBar = activity.getSupportActionBar();
+        if(actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+        }
+
+
         button.setOnClickListener(new View.OnClickListener() {
             private Toast toast; //
             @Override

app/src/main/java/com/example/mampfmobil/ui/supplier/SupplierRegisterFragment.java

 package com.example.mampfmobil.ui.supplier;
 
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.lifecycle.ViewModelProvider;
 
 import android.content.Intent;
@@ -39,6 +41,13 @@ public class SupplierRegisterFragment extends Fragment {
         EditText name = rootView.findViewById(R.id.editTextFirstName);
         EditText register = rootView.findViewById(R.id.editTextAddress);
 
+        AppCompatActivity activity = (AppCompatActivity) requireActivity();
+        // Enable the back button in the ActionBar
+        ActionBar actionBar = activity.getSupportActionBar();
+        if(actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+        }
+
         button.setOnClickListener(new View.OnClickListener() {
             private Toast toast; //
             @Override
@@ -71,6 +80,8 @@ public class SupplierRegisterFragment extends Fragment {
         return rootView;
     }
 
+    
+
     @Override
     public void onActivityCreated(@Nullable Bundle savedInstanceState) {
         super.onActivityCreated(savedInstanceState);