Skip to main content

Simple example of using Fragments in Kotlin | Android

Here is the simple example of using Fragments with Activity in Android.

MainActivity.kt
  
class MainActivity : AppCompatActivity(), BlankFragment.OnFragmentInteractionListener {

    override fun onFragmentInteraction(uri: Uri) {
        TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        setSupportActionBar(toolbar)

        if (savedInstanceState == null) {
            supportFragmentManager.beginTransaction().
                    add(R.id.fragment, BlankFragment.newInstance("Param1", "Param2"), "Second").commit()
        }

        fab.setOnClickListener { view ->
            //Here we will replace the BlanckFragment with SecondFragment.
            supportFragmentManager.beginTransaction().replace(R.id.fragment, SecondFragment(), "Second").commit()
        }
    }
}

activity_main.xml
  
<android.support.design.widget.CoordinatorLayout 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="com.guna.kotlinapplication.MainActivity">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

    </android.support.design.widget.AppBarLayout>

    <include layout="@layout/content_main" />

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:layout_margin="@dimen/fab_margin"
        app:srcCompat="@android:drawable/ic_dialog_email" />

</android.support.design.widget.CoordinatorLayout>

content_main.xml
  
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/fragment"
    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"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.guna.kotlinapplication.MainActivity"
    tools:showIn="@layout/activity_main"/>

We can add static fragment like this. content_main.xml
  
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/fragment"
    class="com.guna.kotlinapplication.BlankFragment"
    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"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.guna.kotlinapplication.MainActivity"
    tools:showIn="@layout/activity_main"/>

BlankFragment.kt 
 
/**
 * A simple [Fragment] subclass.
 * Activities that contain this fragment must implement the
 * [BlankFragment.OnFragmentInteractionListener] interface
 * to handle interaction events.
 * Use the [BlankFragment.newInstance] factory method to
 * create an instance of this fragment.
 */
class BlankFragment : Fragment() {

    // TODO: Rename and change types of parameters
    private var mParam1: String? = null
    private var mParam2: String? = null

    private var mListener: OnFragmentInteractionListener? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        if (arguments != null) {
            mParam1 = arguments!!.getString(ARG_PARAM1)
            mParam2 = arguments!!.getString(ARG_PARAM2)
        }
    }

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                              savedInstanceState: Bundle?): View? {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_blank, container, false)
    }

    // TODO: Rename method, update argument and hook method into UI event
    fun onButtonPressed(uri: Uri) {
        if (mListener != null) {
            mListener!!.onFragmentInteraction(uri)
        }
    }

    override fun onAttach(context: Context?) {
        super.onAttach(context)
        if (context is OnFragmentInteractionListener) {
            mListener = context
        } else {
            throw RuntimeException(context!!.toString() + " must implement OnFragmentInteractionListener")
        }
    }

    override fun onDetach() {
        super.onDetach()
        mListener = null
    }

    /**
     * This interface must be implemented by activities that contain this
     * fragment to allow an interaction in this fragment to be communicated
     * to the activity and potentially other fragments contained in that
     * activity.
     *
     *
     * See the Android Training lesson [Communicating with Other Fragments](http://developer.android.com/training/basics/fragments/communicating.html) for more information.
     */
    interface OnFragmentInteractionListener {
        // TODO: Update argument type and name
        fun onFragmentInteraction(uri: Uri)
    }

    companion object {
        // TODO: Rename parameter arguments, choose names that match
        // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
        private val ARG_PARAM1 = "param1"
        private val ARG_PARAM2 = "param2"

        /**
         * Use this factory method to create a new instance of
         * this fragment using the provided parameters.
         *
         * @param param1 Parameter 1.
         * @param param2 Parameter 2.
         * @return A new instance of fragment BlankFragment.
         */
        // TODO: Rename and change types and number of parameters
        fun newInstance(param1: String, param2: String): BlankFragment {
            val fragment = BlankFragment()
            val args = Bundle()
            args.putString(ARG_PARAM1, param1)
            args.putString(ARG_PARAM2, param2)
            fragment.arguments = args
            return fragment
        }
    }
}// Required empty public constructor

fragment_blank.xml
  
<FrameLayout 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"
    android:background="@color/colorPrimary"
    tools:context="com.guna.kotlinapplication.BlankFragment">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:text="@string/hello_blank_fragment"
        android:textColor="#fff" />

</FrameLayout>

SecondFragment.kt 
 
/**
 * A simple [Fragment] subclass.
 */
class SecondFragment : Fragment() {


    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                              savedInstanceState: Bundle?): View? {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_second, container, false)
    }

}// Required empty public constructor

fragment_second.xml
  
<FrameLayout 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"
    android:background="#567891"
    tools:context="com.guna.kotlinapplication.SecondFragment">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:text="@string/hello_blank_fragment"
        android:textColor="#fff" />

</FrameLayout>


Here is the full video tutorial


Interesting right?


If you are really interested in this code, then please share this post with your friends.


Text WhatsApp message to +91-99654 70689 To join Android Developers WhatsApp group.
Join WhatsApp group by this link
Thank You


Comments

Post a Comment

Popular posts from this blog

Simple example of using Spinner in Kotlin | Android

Though Kotlin has lot massive features to speedup the development time, here is the simple way of using Spinner in Android. In Kotlin we don't need to declare and initialize Spinner. We can simply access the id of Spinner from xml. Ex : import android.os.Bundle import android.support.v7.app.AppCompatActivity import android.view.View import android.widget.AdapterView import android.widget.ArrayAdapter import android.widget.Toast import android.widget.Toast.LENGTH_LONG import kotlinx.android.synthetic.main.activity_main.* class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) //String array. val myStrings = arrayOf("One", "Two", "Three", "Four", "Five") //Adapter for spinner mySpinner.adapter = ArrayAdapter(this, android.R.layout.simple_spinner_dropdown_i...
183 comments
Read more

Simple example of OCRReader in Android.

Hi Friends, Maybe you all heard/used text scanning using camera feature or extracting text from Image. But this sample made it very easy for you. You can made it in very simple line of code. You can download the source code from OCRSample and import the library as a module into your project. Example usage : MainActivity.java public class MainActivity extends AppCompatActivity { private TextView textView; private final int CAMERA_SCAN_TEXT = 0; private final int LOAD_IMAGE_RESULTS = 1; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); textView = findViewById(R.id.textView); } @Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = getMenuInflater(); inflater.inflate(R.menu.menu_main, menu); return super.onCreateOptionsMenu(menu); } @Override public boolean onOptionsItemSele...
32 comments
Read more

Simple RecyclerView example with filter option in Android

Hi Guys, Maybe you all are expert in terms of using RecyclerView in android. This blog is simple example for using filter option with RecyclerView adapter. As for now you will instantiate RecyclerView and set the adapter to RecyclerView as following way. RecyclerView list = (RecyclerView) findViewById(R.id.list); list.setLayoutManager(new LinearLayoutManager(this)); list.setHasFixedSize(true); ArrayList&ltNumber&gt numbers = new ArrayList&lt&gt(); String ONEs[] = {"ZERO", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE", "TEN"}; String TENs[] = {"ZERO", "TEN", "TWENTY", "THIRTY", "FOURTY", "FIFTY", "SIXTY", "SEVENTY", "EIGHTY", "NINETY", "HUNDRED"}; String HUNDREDS[] = {"ZERO", "HUNDRED", "TWO HUND...
58 comments
Read more