Add integer constraint to port preference

app/src/main/java/io/bartek/preference/IntEditTextPreference.kt

@@ -0,0 +1,32 @@
+package io.bartek.preference
+
+import android.content.Context
+import android.util.AttributeSet
+import androidx.preference.EditTextPreference
+import java.lang.Integer.parseInt
+
+class IntEditTextPreference : EditTextPreference {
+    constructor(
+        context: Context?,
+        attrs: AttributeSet?,
+        defStyleAttr: Int,
+        defStyleRes: Int
+    ) : super(context, attrs, defStyleAttr, defStyleRes)
+
+    constructor(
+        context: Context?,
+        attrs: AttributeSet?,
+        defStyleAttr: Int
+    ) : super(context, attrs, defStyleAttr)
+
+    constructor(context: Context?, attrs: AttributeSet?) : super(context, attrs)
+
+    constructor(context: Context?) : super(context)
+
+    override fun getPersistedString(defaultReturnValue: String?) =
+        getPersistedInt(Integer.valueOf(defaultReturnValue ?: "-1")).toString()
+
+    override fun persistString(value: String?) = persistInt(Integer.valueOf(value ?: "-1"))
+
+
+}

app/src/main/java/io/bartek/preference/PreferencesFragment.kt

@@ -2,14 +2,14 @@ package io.bartek.preference
 
 import android.content.Intent
 import android.os.Bundle
-import androidx.preference.EditTextPreference
+import android.text.InputType
 import androidx.preference.Preference
 import androidx.preference.PreferenceFragmentCompat
 import androidx.preference.SwitchPreference
 import io.bartek.R
 
 class PreferencesFragment : PreferenceFragmentCompat() {
-    private lateinit var portPreference: EditTextPreference
+    private lateinit var portPreference: IntEditTextPreference
     private lateinit var sayEndpointPreference: SwitchPreference
     private lateinit var waveEndpointPreference: SwitchPreference
     private lateinit var ttsEnginePreference: Preference
@@ -17,6 +17,7 @@ class PreferencesFragment : PreferenceFragmentCompat() {
     override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
         setPreferencesFromResource(R.xml.preferences, rootKey)
         portPreference = findPreference("preference_port")!!
+        portPreference.setOnBindEditTextListener { it.inputType = InputType.TYPE_CLASS_NUMBER }
         sayEndpointPreference = findPreference("preference_enable_say_endpoint")!!
         waveEndpointPreference = findPreference("preference_enable_wave_endpoint")!!
         ttsEnginePreference = findPreference("preference_tts")!!

app/src/main/java/io/bartek/service/ForegroundService.kt

@@ -22,7 +22,7 @@ class ForegroundService : Service() {
     private var isServiceStarted = false
     private var ttsServer: TTSServer? = null
     private val port: Int
-        get() = parseInt(preferences.getString("preference_port", "8080")!!)
+        get() = preferences.getInt("preference_port", 8080)
 
     override fun onCreate() {
         super.onCreate()

app/src/main/res/xml/preferences.xml

@@ -2,7 +2,7 @@
 <androidx.preference.PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto">
     <PreferenceCategory android:title="@string/preference_category_server" app:iconSpaceReserved="false">
-        <EditTextPreference
+        <io.bartek.preference.IntEditTextPreference
             android:defaultValue="8080"
             android:inputType="number"
             android:key="preference_port"