created hidden settings menu for ab-testing

app/src/main/AndroidManifest.xml

@@ -41,6 +41,11 @@
             </intent-filter>
         </activity>
 
+        <activity
+            android:name=".ui.DevSettingsActivity"
+            android:exported="false"
+            android:parentActivityName=".MainActivity" />
+
     </application>
 
 </manifest>

app/src/main/java/com/dano/test1/ui/AbTestSettingsStore.kt

@@ -0,0 +1,46 @@
+package com.dano.test1.ui
+
+import android.content.Context
+
+/**
+ * Persists dev-only A/B overrides. Not a security boundary; values are for local QA.
+ * Use [effectiveVariant] when branching questionnaire or remote-config logic.
+ */
+object AbTestSettingsStore {
+    private const val PREF = "dev_ab_settings"
+    private const val KEY_OVERRIDE = "override_enabled"
+    private const val KEY_VARIANT = "variant"
+
+    const val VARIANT_NONE = "NONE"
+    const val VARIANT_A = "A"
+    const val VARIANT_B = "B"
+
+    fun isOverrideEnabled(context: Context): Boolean =
+        context.getSharedPreferences(PREF, Context.MODE_PRIVATE).getBoolean(KEY_OVERRIDE, false)
+
+    fun setOverrideEnabled(context: Context, enabled: Boolean) {
+        context.getSharedPreferences(PREF, Context.MODE_PRIVATE).edit()
+            .putBoolean(KEY_OVERRIDE, enabled)
+            .apply()
+    }
+
+    fun getVariant(context: Context): String =
+        context.getSharedPreferences(PREF, Context.MODE_PRIVATE).getString(KEY_VARIANT, VARIANT_NONE)
+            ?: VARIANT_NONE
+
+    fun setVariant(context: Context, variant: String) {
+        context.getSharedPreferences(PREF, Context.MODE_PRIVATE).edit()
+            .putString(KEY_VARIANT, variant)
+            .apply()
+    }
+
+    /** Returns "A" or "B" when override is on and a branch is selected; otherwise null. */
+    fun effectiveVariant(context: Context): String? {
+        if (!isOverrideEnabled(context)) return null
+        return when (getVariant(context)) {
+            VARIANT_A -> "A"
+            VARIANT_B -> "B"
+            else -> null
+        }
+    }
+}

app/src/main/java/com/dano/test1/ui/DevSettingsActivity.kt

@@ -0,0 +1,71 @@
+package com.dano.test1.ui
+
+import android.os.Bundle
+import android.widget.RadioButton
+import android.widget.RadioGroup
+import androidx.appcompat.app.AppCompatActivity
+import androidx.appcompat.widget.SwitchCompat
+import androidx.appcompat.widget.Toolbar
+import com.dano.test1.R
+
+/**
+ * Dev-only A/B settings. Entry: client code [_dev_settings_] on the opening screen Load action.
+ * Not a security boundary (secret string is in the APK).
+ */
+class DevSettingsActivity : AppCompatActivity() {
+
+    private lateinit var switchOverride: SwitchCompat
+    private lateinit var radioGroup: RadioGroup
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_dev_settings)
+
+        val toolbar = findViewById<Toolbar>(R.id.devSettingsToolbar)
+        setSupportActionBar(toolbar)
+        supportActionBar?.setDisplayHomeAsUpEnabled(true)
+
+        switchOverride = findViewById(R.id.switchAbOverride)
+        radioGroup = findViewById(R.id.radioGroupVariant)
+
+        applyPrefsToUi()
+
+        switchOverride.setOnCheckedChangeListener { _, isChecked ->
+            AbTestSettingsStore.setOverrideEnabled(this, isChecked)
+            updateRadiosEnabled(isChecked)
+        }
+
+        radioGroup.setOnCheckedChangeListener { _, checkedId ->
+            val variant = when (checkedId) {
+                R.id.radioVariantA -> AbTestSettingsStore.VARIANT_A
+                R.id.radioVariantB -> AbTestSettingsStore.VARIANT_B
+                else -> AbTestSettingsStore.VARIANT_NONE
+            }
+            AbTestSettingsStore.setVariant(this, variant)
+        }
+    }
+
+    private fun applyPrefsToUi() {
+        val overrideOn = AbTestSettingsStore.isOverrideEnabled(this)
+        switchOverride.isChecked = overrideOn
+        updateRadiosEnabled(overrideOn)
+
+        when (AbTestSettingsStore.getVariant(this)) {
+            AbTestSettingsStore.VARIANT_A -> radioGroup.check(R.id.radioVariantA)
+            AbTestSettingsStore.VARIANT_B -> radioGroup.check(R.id.radioVariantB)
+            else -> radioGroup.check(R.id.radioVariantDefault)
+        }
+    }
+
+    private fun updateRadiosEnabled(enabled: Boolean) {
+        for (i in 0 until radioGroup.childCount) {
+            (radioGroup.getChildAt(i) as? RadioButton)?.isEnabled = enabled
+        }
+        radioGroup.alpha = if (enabled) 1f else 0.5f
+    }
+
+    override fun onSupportNavigateUp(): Boolean {
+        finish()
+        return true
+    }
+}

app/src/main/java/com/dano/test1/ui/LoadButtonHandler.kt

@@ -1,5 +1,6 @@
 package com.dano.test1.ui
 
+import android.content.Intent
 import android.widget.Button
 import android.widget.EditText
 import android.widget.Toast
@@ -24,6 +25,11 @@ class LoadButtonHandler(
     private val updateMainButtonsState: (Boolean) -> Unit,
 ) {
 
+    companion object {
+        /** Opening-screen client code that opens dev A/B settings (not a security boundary). */
+        private const val DEV_SETTINGS_SECRET = "_dev_settings_"
+    }
+
     fun setup() {
         loadButton.text = LanguageManager.getText(languageIDProvider(), "load")
         loadButton.setOnClickListener { handleLoadButton() }
@@ -37,6 +43,12 @@ class LoadButtonHandler(
             return
         }
 
+        if (inputText == DEV_SETTINGS_SECRET) {
+            editText.text.clear()
+            activity.startActivity(Intent(activity, DevSettingsActivity::class.java))
+            return
+        }
+
         buttonPoints.clear()
         setButtonsEnabled(emptyList())   // temporär sperren
         updateButtonTexts()              // Chips zeigen vorläufig „Gesperrt“

app/src/main/res/layout/activity_dev_settings.xml

@@ -0,0 +1,75 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <androidx.appcompat.widget.Toolbar
+        android:id="@+id/devSettingsToolbar"
+        android:layout_width="match_parent"
+        android:layout_height="?attr/actionBarSize"
+        android:background="?attr/colorPrimary"
+        app:title="A/B testing (dev)"
+        app:titleTextColor="@android:color/white" />
+
+    <ScrollView
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:fillViewport="true">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="vertical"
+            android:padding="16dp">
+
+            <TextView
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:paddingBottom="8dp"
+                android:text="Manual A/B override for local testing. Not a security boundary."
+                android:textSize="14sp" />
+
+            <androidx.appcompat.widget.SwitchCompat
+                android:id="@+id/switchAbOverride"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:paddingVertical="8dp"
+                android:text="Manual A/B override" />
+
+            <TextView
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:paddingTop="16dp"
+                android:paddingBottom="8dp"
+                android:text="Variant"
+                android:textStyle="bold" />
+
+            <RadioGroup
+                android:id="@+id/radioGroupVariant"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:orientation="vertical">
+
+                <RadioButton
+                    android:id="@+id/radioVariantDefault"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:text="Default (no override)" />
+
+                <RadioButton
+                    android:id="@+id/radioVariantA"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:text="Variant A" />
+
+                <RadioButton
+                    android:id="@+id/radioVariantB"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:text="Variant B" />
+            </RadioGroup>
+        </LinearLayout>
+    </ScrollView>
+</LinearLayout>