KeyHandler: Add customization options

Change-Id: I5f50f5d442342b2082bf47e11b1351e578fa0144

KeyHandler/src/org/lineageos/settings/device/ButtonSettingsFragment.kt

@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2021 The LineageOS Project
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.lineageos.settings.device
+
+import android.os.Bundle
+import android.view.MenuItem
+import androidx.preference.PreferenceFragment
+
+class ButtonSettingsFragment : PreferenceFragment() {
+    override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
+        addPreferencesFromResource(R.xml.button_panel)
+        activity.actionBar!!.setDisplayHomeAsUpEnabled(true)
+    }
+
+    override fun addPreferencesFromResource(preferencesResId: Int) {
+        super.addPreferencesFromResource(preferencesResId)
+    }
+
+    override fun onOptionsItemSelected(item: MenuItem): Boolean {
+        when (item.itemId) {
+            R.id.home -> {
+                activity.finish()
+                return true
+            }
+        }
+        return super.onOptionsItemSelected(item)
+    }
+}