SwitchCompat Unresolved reference - Android Kotlin

Question

I'm using a SwitchCompat in a fragment where I keep getting and Unresolved reference that don't let me compile. I don't know where to look at any more.. I believe I have my gradle files how they are supposed to be but I still suspect is something from there.. Any idea what I might be doing wrong?

Thank you in advance!! Any tip would be very appreciated

My gradle files:

// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
    ext.kotlin_version = "1.4.21"
    ext.nav_version = '2.3.0'
    repositories {
        google()
        jcenter()
    }
    dependencies {
        classpath "com.android.tools.build:gradle:4.1.1"
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath "androidx.navigation:navigation-safe-args-gradle-plugin:$nav_version"

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

And:

plugins {
    id 'com.android.application'
    id 'kotlin-android'
    id 'androidx.navigation.safeargs.kotlin'
}

android {
    compileSdkVersion 30
    buildToolsVersion "30.0.2"

    defaultConfig {
        applicationId "com.example.onemorepassword"
        minSdkVersion 21
        targetSdkVersion 30
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }

    buildFeatures {
        dataBinding true
    }

}

dependencies {

    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    implementation 'androidx.core:core-ktx:1.3.2'
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'com.google.android.material:material:1.2.1'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
    implementation "androidx.navigation:navigation-fragment-ktx:$nav_version"
    implementation "androidx.navigation:navigation-ui-ktx:$nav_version"
    testImplementation 'junit:junit:4.+'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'

    //ViewModel
    implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.2.0'
}

I have my XML:

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools">

    <androidx.constraintlayout.widget.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <androidx.appcompat.widget.SwitchCompat
            android:id="@+id/lowLetters_switch"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginStart="16dp"
            android:layout_marginTop="30dp"
            android:checked="true"
            android:fontFamily="@font/nunito_sans_bold"
            android:text="@string/switchLowLetters"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/lengthSize_seekBar" />

    </androidx.constraintlayout.widget.ConstraintLayout>
</layout>

My Fragment:

package com.example.onemorepassword

import android.annotation.SuppressLint
import android.content.ClipData
import android.content.ClipboardManager
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.view.animation.Animation
import android.view.animation.AnimationUtils
import android.widget.Button
import android.widget.SeekBar
import android.widget.TextView
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import androidx.core.content.ContextCompat
import androidx.databinding.DataBindingUtil
import androidx.fragment.app.Fragment
import androidx.lifecycle.ViewModelProvider
import com.example.onemorepassword.databinding.OneMorePasswordFragmentBinding

class OneMorePasswordFragment : Fragment() {

    private lateinit var binding: OneMorePasswordFragmentBinding
    private lateinit var viewModel: OneMorePasswordViewModel

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        binding = DataBindingUtil.inflate<OneMorePasswordFragmentBinding>(inflater, R.layout.one_more_password_fragment, container, false)

        viewModel = ViewModelProvider(this).get(OneMorePasswordViewModel::class.java)

        //All fun that update UI from viewModel
        savedGeneratedPass()

        return binding.root
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        **val myLowLettersSwitch = binding.lowLettersSwitch
        myLowLettersSwitch.setOnCheckedChangeListener { _, b ->
            Toast.makeText(requireActivity(),b.toString(),Toast.LENGTH_SHORT).show(**)
        }

......
More code...
....

    **private fun switchLowLetters(): Boolean {
        val myLowLettersSwitch= binding.lowLettersSwitch
        return myLowLettersSwitch.isChecked
    }**

....
More code...

And last my mainActivity

package com.example.onemorepassword

import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import androidx.databinding.DataBindingUtil
import com.example.onemorepassword.databinding.ActivityMainBinding

class MainActivity : AppCompatActivity() {

    private lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        //setContentView(R.layout.activity_main)
        binding = DataBindingUtil.setContentView(this, R.layout.activity_main)

        supportActionBar?.hide()
    }
}

Answer 1

You need to add viewBinding true to buildFeatures in build.gradle (app) file in order to be able to use view binding.

Just replace:

buildFeatures {
    dataBinding true
}

with:

buildFeatures {
    dataBinding true
    viewBinding true
}

Answer 2

Found out what was happening. Once you know it..!

I have to XML files for same Fragment, Portrait and Landscape. Forgot to edit me Landscape XML file.... So in one I had <com.google.android.material.switchmaterial.SwitchMaterial> (or compat, does not matter)

and in other XML I only had

Maybe this will serve for someone to look into this before collapsing