I have created a bottom menu bar using material , with five fragments. I have created xml file of each fragment along with their kt files. Also I have applied View Binding but the issue is when I use binding to refer to my buttons or text views from my fragments in the Main Activity.kt , I am Unable to do so. Below i have inflated the fragement in its kt file, have a look at it.
convert_fargment.xml This is the xml file of the feagment
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingHorizontal="32dp"
tools:context=".fragments.ConvertFragment">
<TextView
android:id="@+id/tvTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="92dp"
android:text="Converter"
android:textColor="@color/black"
android:textSize="35sp"
app:layout_constraintBottom_toTopOf="@+id/guideline2"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.564" />
<TextView
android:id="@+id/tvFrom"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="From "
app:layout_constraintStart_toStartOf="@+id/spFromCurrency"
app:layout_constraintTop_toTopOf="@+id/guideline2" />
<TextView
android:id="@+id/tvTo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="To "
app:layout_constraintStart_toStartOf="@+id/spToCurrency"
app:layout_constraintTop_toTopOf="@+id/guideline2" />
<com.google.android.material.textfield.TextInputLayout
android:id="@+id/tilFrom"
style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox.Dense"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:hint="Amount"
app:layout_constraintBottom_toBottomOf="@+id/spFromCurrency"
app:layout_constraintEnd_toStartOf="@+id/spFromCurrency"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/spFromCurrency">
<com.google.android.material.textfield.TextInputEditText
android:id="@+id/etFrom"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:inputType="numberDecimal"
tools:layout_editor_absoluteX="-3dp"
tools:layout_editor_absoluteY="153dp" />
</com.google.android.material.textfield.TextInputLayout>
<androidx.constraintlayout.widget.Guideline
android:id="@+id/guideline2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_percent="0.32" />
<Spinner
android:id="@+id/spFromCurrency"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:entries="@array/currency_codes"
android:padding="15dp"
app:layout_constraintEnd_toStartOf="@+id/spToCurrency"
app:layout_constraintTop_toBottomOf="@+id/tvFrom" />
<Button
android:id="@+id/btnConvert"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:text="Convert"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="@+id/spToCurrency" />
<TextView
android:id="@+id/tvResult"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:textColor="@color/black"
app:layout_constraintBottom_toBottomOf="@+id/btnConvert"
app:layout_constraintEnd_toStartOf="@+id/btnConvert"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/btnConvert"
app:layout_constraintVertical_bias="0.586"
tools:text="10 EUR = 15.0 USD" />
<ProgressBar
android:id="@+id/progresBar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
app:layout_constraintBottom_toBottomOf="@+id/btnConvert"
app:layout_constraintEnd_toStartOf="@+id/btnConvert"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/btnConvert"
tools:visibility="invisible" />
<Spinner
android:id="@+id/spToCurrency"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:entries="@array/currency_codes"
android:padding="15dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="@+id/tvTo" />
</androidx.constraintlayout.widget.ConstraintLayout>
ConvertFragment.kt This is the kt file of the fragment.
package com.example.currency.fragments
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.fragment.app.Fragment
import androidx.fragment.app.viewModels
import com.example.currency.R
import com.example.currency.databinding.FragmentConvertBinding
import com.example.currency.main.MainViewModel
class ConvertFragment : Fragment(R.layout.fragment_convert) {
private val viewModel: MainViewModel by viewModels()
private var _binding: FragmentConvertBinding? = null
private val binding get() = _binding!!
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
_binding = FragmentConvertBinding.inflate(inflater,container,false)
binding.btnConvert
return binding.root
}
override fun onDestroyView() {
super.onDestroyView()
_binding = null
}
}
MainActivity.kt This is the Main activity file
package com.example.currency
import android.os.Bundle
import androidx.activity.viewModels
import androidx.appcompat.app.AppCompatActivity
import androidx.appcompat.app.AppCompatDelegate
import androidx.fragment.app.Fragment
import com.example.currency.databinding.ActivityMainBinding
import com.example.currency.fragments.*
import com.example.currency.main.MainViewModel
class MainActivity : AppCompatActivity() {
private lateinit var binding: ActivityMainBinding
private val viewModel: MainViewModel by viewModels()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(layoutInflater)
setContentView(binding.root)
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_NO)
val convertFragment = ConvertFragment()
val chartsFragment = ChartsFragment()
val sendFragment = SendFragment()
val favoritesFragment = FavoritesFragment()
val moreFragment = MoreFragment()
makeCurrentFragment(convertFragment)
binding.bottomNavigation.setOnNavigationItemSelectedListener {
when (it.itemId){
R.id.ic_rupee -> makeCurrentFragment(convertFragment)
R.id.ic_charts -> makeCurrentFragment(chartsFragment)
R.id.ic_send_money -> makeCurrentFragment(sendFragment)
R.id.ic_favorites -> makeCurrentFragment(favoritesFragment)
R.id.ic_more -> makeCurrentFragment(moreFragment)
}
true
}
}
private fun makeCurrentFragment(fragment: Fragment) =
supportFragmentManager.beginTransaction().apply {
replace(R.id.fl_wrapper, fragment)
commit()
}
}
activity_main.xml This is the xml file of main activity
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:background="#EEEEEE">
<FrameLayout
android:id="@+id/fl_wrapper"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintBottom_toTopOf="@+id/bottom_navigation"/>
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="@+id/bottom_navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="?android:attr/windowBackground"
app:itemBackground="@color/purple_700"
app:itemIconTint="@color/white"
app:itemTextColor="@color/white"
app:menu="@menu/nav_menu"/>
</RelativeLayout>
