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Fix Navigation Component Not Working in Kotlin

If you’re facing issues where the Navigation Component is not working in Kotlin, you’re not alone. Many Android developers encounter…

If you’re facing issues where the Navigation Component is not working in Kotlin, you’re not alone. Many Android developers encounter crashes, blank screens, or navigation not responding as expected. This article walks you through the common causes, how to resolve them, and includes a full working example separated by class.

Navigation Component Kotlin

Common Problems

  1. Missing NavHostFragment
  2. Incorrect navigation graph reference
  3. Wrong Fragment or Activity setup
  4. Incomplete dependencies or lifecycle setup

Full Working Example Using Navigation Component

1. build.gradle (app level)

dependencies {
    implementation "androidx.navigation:navigation-fragment-ktx:2.7.0"
    implementation "androidx.navigation:navigation-ui-ktx:2.7.0"
}

2. res/navigation/nav_graph.xml

<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/nav_graph"
    app:startDestination="@id/homeFragment">

    <fragment
        android:id="@+id/homeFragment"
        android:name="com.example.app.HomeFragment"
        android:label="Home" >
        <action
            android:id="@+id/action_homeFragment_to_detailFragment"
            app:destination="@id/detailFragment" />
    </fragment>

    <fragment
        android:id="@+id/detailFragment"
        android:name="com.example.app.DetailFragment"
        android:label="Detail" />
</navigation>

3. MainActivity.kt

package com.example.app

import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import androidx.navigation.fragment.NavHostFragment
import androidx.navigation.ui.setupActionBarWithNavController

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val navHostFragment = supportFragmentManager
            .findFragmentById(R.id.nav_host_fragment_container) as NavHostFragment
        val navController = navHostFragment.navController

        setupActionBarWithNavController(navController)
    }

    override fun onSupportNavigateUp(): Boolean {
        val navController = supportFragmentManager
            .findFragmentById(R.id.nav_host_fragment_container)
            ?.findNavController()
        return navController?.navigateUp() ?: false
    }
}

4. activity_main.xml

<androidx.fragment.app.FragmentContainerView
    android:id="@+id/nav_host_fragment_container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:navGraph="@navigation/nav_graph"
    app:defaultNavHost="true"
    android:name="androidx.navigation.fragment.NavHostFragment" />

5. HomeFragment.kt

package com.example.app

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.fragment.app.Fragment
import androidx.navigation.fragment.findNavController
import com.example.app.databinding.FragmentHomeBinding

class HomeFragment : Fragment() {
    private lateinit var binding: FragmentHomeBinding

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?
    ): View {
        binding = FragmentHomeBinding.inflate(inflater, container, false)
        return binding.root
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        binding.buttonNavigate.setOnClickListener {
            findNavController().navigate(R.id.action_homeFragment_to_detailFragment)
        }
    }
}

6. DetailFragment.kt

package com.example.app

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.fragment.app.Fragment
import com.example.app.databinding.FragmentDetailBinding

class DetailFragment : Fragment() {
    private lateinit var binding: FragmentDetailBinding

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?
    ): View {
        binding = FragmentDetailBinding.inflate(inflater, container, false)
        return binding.root
    }
}

Tips for Debugging

  • Ensure you’re using the correct NavHostFragment
  • Use findNavController() within Fragments
  • Use setupActionBarWithNavController() if needed
  • Avoid calling navigate() before view is created

For more guidance on Android Navigation Component, check the official documentation.

rysasahrial

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