Sat. Dec 21st, 2024

AndroIndian

Simplify Learning

Android With Kotlin

Simple Fragment example in Fragment

ByRajashekar

Nov 6, 2023

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<layout>
<LinearLayout 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:orientation="vertical">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Fragment example"
         />
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="fragment one"
        android:id="@+id/fragone"/>

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="fragment two"
        android:id="@+id/fragtwo"/>

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/frame"
        android:background="#00BCD4"/>

</LinearLayout>
</layout>

MainActivity.kt

package com.androindian.fragment

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.databinding.DataBindingUtil
import androidx.fragment.app.FragmentManager
import com.androindian.fragment.databinding.ActivityMainBinding
import com.androindian.fragment.ui.login.SecondFrag

class MainActivity : AppCompatActivity() {

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

        binding?.fragone?.setOnClickListener {
            var fragmentmanager: FragmentManager=supportFragmentManager
            var fragmentTransaction=fragmentmanager.beginTransaction()
            var firstFrag=FirstFrag()
            fragmentTransaction.replace(R.id.frame,firstFrag)
            fragmentTransaction.commit()
        }

        binding?.fragtwo?.setOnClickListener {
            var fragmentmanager: FragmentManager=supportFragmentManager
            var fragmentTransaction=fragmentmanager.beginTransaction()
            var secondFrag= SecondFrag()
            fragmentTransaction.replace(R.id.frame,secondFrag)
            fragmentTransaction.commit()
        }
    }
}

FirstFrag.kt

package com.androindian.fragment

import android.content.Intent
import android.os.Bundle
import androidx.fragment.app.Fragment
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Button
import androidx.databinding.DataBindingUtil
import com.androindian.fragment.databinding.FragmentFirstBinding


class FirstFrag : Fragment() {

    var binding: FragmentFirstBinding?=null


    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        // Inflate the layout for this fragment
        var view: View
        //view=inflater.inflate(R.layout.fragment_first, container, false)
        binding=DataBindingUtil.inflate(inflater,
            R.layout.fragment_first, container, false)

       // var button: Button?=null
        //button=view?.findViewById(R.id.bt)

        binding?.bt?.setOnClickListener {
            var intent=Intent(context,Registr::class.java)
            startActivity(intent)
        }


            return binding?.root
    }




}

fragment_first.xml

<?xml version="1.0" encoding="utf-8"?>
<layout>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".FirstFrag"
    android:orientation="vertical">

    <!-- TODO: Update blank fragment layout -->
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello_blank_fragment" />

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/bt"
        android:text="Hellow frag"/>

</LinearLayout>
</layout>

second_frag.kt

package com.androindian.fragment.ui.login

import androidx.lifecycle.Observer
import androidx.lifecycle.ViewModelProvider
import androidx.annotation.StringRes
import androidx.fragment.app.Fragment
import android.os.Bundle
import android.text.Editable
import android.text.TextWatcher
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.view.inputmethod.EditorInfo
import android.widget.Button
import android.widget.EditText
import android.widget.ProgressBar
import android.widget.Toast
import com.androindian.fragment.databinding.FragmentSecondBinding

import com.androindian.fragment.R

class SecondFrag : Fragment() {

    private lateinit var loginViewModel: LoginViewModel
    private var _binding: FragmentSecondBinding? = null

    // This property is only valid between onCreateView and
    // onDestroyView.
    private val binding get() = _binding!!

    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {

        _binding = FragmentSecondBinding.inflate(inflater, container, false)
        return binding.root

    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        loginViewModel = ViewModelProvider(this, LoginViewModelFactory())
            .get(LoginViewModel::class.java)

        val usernameEditText = binding.username
        val passwordEditText = binding.password
        val loginButton = binding.login
        val loadingProgressBar = binding.loading

        loginViewModel.loginFormState.observe(viewLifecycleOwner,
            Observer { loginFormState ->
                if (loginFormState == null) {
                    return@Observer
                }
                loginButton.isEnabled = loginFormState.isDataValid
                loginFormState.usernameError?.let {
                    usernameEditText.error = getString(it)
                }
                loginFormState.passwordError?.let {
                    passwordEditText.error = getString(it)
                }
            })

        loginViewModel.loginResult.observe(viewLifecycleOwner,
            Observer { loginResult ->
                loginResult ?: return@Observer
                loadingProgressBar.visibility = View.GONE
                loginResult.error?.let {
                    showLoginFailed(it)
                }
                loginResult.success?.let {
                    updateUiWithUser(it)
                }
            })

        val afterTextChangedListener = object : TextWatcher {
            override fun beforeTextChanged(s: CharSequence, start: Int, count: Int, after: Int) {
                // ignore
            }

            override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
                // ignore
            }

            override fun afterTextChanged(s: Editable) {
                loginViewModel.loginDataChanged(
                    usernameEditText.text.toString(),
                    passwordEditText.text.toString()
                )
            }
        }
        usernameEditText.addTextChangedListener(afterTextChangedListener)
        passwordEditText.addTextChangedListener(afterTextChangedListener)
        passwordEditText.setOnEditorActionListener { _, actionId, _ ->
            if (actionId == EditorInfo.IME_ACTION_DONE) {
                loginViewModel.login(
                    usernameEditText.text.toString(),
                    passwordEditText.text.toString()
                )
            }
            false
        }

        loginButton.setOnClickListener {
            loadingProgressBar.visibility = View.VISIBLE
            loginViewModel.login(
                usernameEditText.text.toString(),
                passwordEditText.text.toString()
            )
        }
    }

    private fun updateUiWithUser(model: LoggedInUserView) {
        val welcome = getString(R.string.welcome) + model.displayName
        // TODO : initiate successful logged in experience
        val appContext = context?.applicationContext ?: return
        Toast.makeText(appContext, welcome, Toast.LENGTH_LONG).show()
    }

    private fun showLoginFailed(@StringRes errorString: Int) {
        val appContext = context?.applicationContext ?: return
        Toast.makeText(appContext, errorString, Toast.LENGTH_LONG).show()
    }

    override fun onDestroyView() {
        super.onDestroyView()
        _binding = null
    }
}

activity_second.xml

<?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:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/fragment_horizontal_margin"
    android:paddingTop="@dimen/fragment_vertical_margin"
    android:paddingRight="@dimen/fragment_horizontal_margin"
    android:paddingBottom="@dimen/fragment_vertical_margin"
    tools:context=".ui.login.SecondFrag">

    <EditText
        android:id="@+id/username"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="24dp"
        android:layout_marginTop="96dp"
        android:layout_marginEnd="24dp"
        android:hint="@string/prompt_email"
        android:inputType="textEmailAddress"
        android:selectAllOnFocus="true"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/password"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="24dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="24dp"
        android:hint="@string/prompt_password"
        android:imeActionLabel="@string/action_sign_in_short"
        android:imeOptions="actionDone"
        android:inputType="textPassword"
        android:selectAllOnFocus="true"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/username" />

    <Button
        android:id="@+id/login"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="start"
        android:layout_marginStart="48dp"
        android:layout_marginTop="16dp"
        android:layout_marginEnd="48dp"
        android:layout_marginBottom="64dp"
        android:enabled="false"
        android:text="@string/action_sign_in"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/password"
        app:layout_constraintVertical_bias="0.2" />

    <ProgressBar
        android:id="@+id/loading"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginStart="32dp"
        android:layout_marginTop="64dp"
        android:layout_marginEnd="32dp"
        android:layout_marginBottom="64dp"
        android:visibility="gone"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="@+id/password"
        app:layout_constraintStart_toStartOf="@+id/password"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.3" />
</androidx.constraintlayout.widget.ConstraintLayout>

Registr.kt

package com.androindian.fragment

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle

class Registr : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_registr)
    }
}

activity_regstr.xml

<?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"
    tools:context=".Registr">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Reg"
        tools:layout_editor_absoluteX="144dp"
        tools:layout_editor_absoluteY="170dp" />
</androidx.constraintlayout.widget.ConstraintLayout>

androidManifest.xml

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

    <application
        android:allowBackup="true"
        android:dataExtractionRules="@xml/data_extraction_rules"
        android:fullBackupContent="@xml/backup_rules"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.Fragment"
        tools:targetApi="31">
        <activity
            android:name=".Registr"
            android:exported="false" />
        <activity
            android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

By Rajashekar

I’m (Rajashekar) a core Android developer with complimenting skills as a web developer from India. I cherish taking up complex problems and turning them into beautiful interfaces. My love for decrypting the logic and structure of coding keeps me pushing towards writing elegant and proficient code, whether it is Android, PHP, Flutter or any other platforms. You would find me involved in cuisines, reading, travelling during my leisure hours.

Related Post

Android With Kotlin

What are Android Architecture Components?

Dec 15, 2024 Rajashekar
Android With Kotlin

Get current location Latitude and Longitude

Nov 27, 2024 Rajashekar
Android With Kotlin

What is SOLID

Nov 21, 2024 Rajashekar

Leave a Reply

Your email address will not be published. Required fields are marked *

You missed

Project Management

Project Management Tips

Dec 17, 2024 Rajashekar
Android With Kotlin

What are Android Architecture Components?

Dec 15, 2024 Rajashekar
AI

The best AI meeting assistants: tl‎;dv

Dec 11, 2024 Rajashekar
AI

The best AI project management tools-ClickUp

Dec 11, 2024 Rajashekar