Greetings!
We have recently published 100+ articles on android tutorials with kotlin and java. If you need, you may visit Android Tutorial for beginners page. You can also check Kotlin Tutorial for beginners. Also, if you are interested in content writing, you can mail us at tutorialwing@gmail.com.Hello Readers! In this post, we are going to learn about how to use android floating action button programmatically in kotlin in the application. We will also learn how to add floating action button to linearLayout programmatically in android application.
Output

Dynamic Floating Action Button Output
Getting Started
At first, we will create android project. Then, we will create and use floating action button programmatically in kotlin file.
1. Creating New Project in Kotlin
Follow the steps below to create new project. Please ignore the steps if you have already created a new project.
Step | Description |
---|---|
1. | Open Android Studio. |
2. | Go to File => New => New Project. Write application name as DynamicFloatingActionButton. Then, check Include Kotlin Support and click next button. |
3. | Select minimum SDK you need. However, we have selected 17 as minimum SDK. Then, click next button |
4. | Then, select Empty Activity => click next => click finish. |
5. | At this point, You will get a newly created android project successfully. |
Now, we will modify xml and kotlin file to use floating action button dynamically.
2. Modify Values Folder
Open res/values/strings.xml file. Then, add below code into it.
<resources> <string name="app_name">DynamicFloatingActionButton</string> <string name="message">Floating Action Button has been created dynamically. Click on it to see Toast message.</string> </resources>
Now, open res/values/styles.xml file and add below code into it.
<resources> <!-- Base application theme. --> <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar"> <!-- Customize your theme here. --> <item name="colorPrimary">@color/colorPrimary</item> <item name="colorPrimaryDark">@color/colorPrimaryDark</item> <item name="colorAccent">@color/colorAccent</item> </style> <style name="AppTheme.AppBarOverlay" parent="AppTheme"> </style> <style name="AppTheme.PopupOverlay" parent="AppTheme"> </style> </resources>
3. Define main content xml file
Now, we will add an xml file that will contains main UI for the application. So, create an xml file, named content_main.xml, in res/layout/content_main.xml. Then, add below code into it.
<?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" app:layout_behavior="@string/appbar_scrolling_view_behavior" tools:showIn="@layout/activity_main"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerInParent="true" android:layout_margin="40dp" android:text="@string/message"/> </RelativeLayout>
Note – This is optional step. You may not need to add this file based on your application structures.
4. Modify Layout Folder
Open res/layout/activity_main.xml file. Then, add below code into it.
<?xml version="1.0" encoding="utf-8"?> <android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="match_parent" android:fitsSystemWindows="true"> <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="?android:attr/actionBarSize" android:background="@color/colorPrimary" app:popupTheme="@style/AppTheme.PopupOverlay" app:titleTextColor="@android:color/white"/> </android.support.design.widget.AppBarLayout> <include layout="@layout/content_main"/> <LinearLayout android:id="@+id/rootContainer" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="bottom|end" android:orientation="vertical"> </LinearLayout> </android.support.design.widget.CoordinatorLayout>
5. Create Android Floating Action Button Programmatically / Dynamically in Kotlin
Open app/src/main/java/com.tutorialwing.dynamicfloatingactionbutton/MainActivity.kt file. Then, add below code into it.
package com.tutorialwing.dynamicfloatingactionbutton import android.os.Bundle import android.support.design.widget.FloatingActionButton import android.support.v7.app.AppCompatActivity import android.support.v7.widget.Toolbar import android.view.ViewGroup import android.widget.LinearLayout import android.widget.Toast class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) val toolbar = findViewById<Toolbar>(R.id.toolbar) setSupportActionBar(toolbar) val floatingActionButton = FloatingActionButton(this) val layoutParams = LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT) layoutParams.setMargins(32, 32, 32, 32) floatingActionButton.layoutParams = layoutParams floatingActionButton.setImageResource(android.R.drawable.ic_dialog_email) floatingActionButton.setOnClickListener { // We are showing only toast message. However, you can do anything you need. Toast.makeText(applicationContext, "You clicked Floating Action Button", Toast.LENGTH_SHORT).show() } val linearLayout = findViewById<LinearLayout>(R.id.rootContainer) linearLayout?.addView(floatingActionButton) } }
Since AndroidManifest.xml file is very important in any android application, we are also going to see the content inside this file.
AndroidManifest.xml file
Code inside src/main/AndroidManifest.xml file is –
<?xml version="1.0" encoding="utf-8"?> <manifest package="com.tutorialwing.dynamicfloatingactionbutton" xmlns:android="http://schemas.android.com/apk/res/android"> <application android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round" android:supportsRtl="true" android:theme="@style/AppTheme"> <activity android:name=".MainActivity"> <intent-filter> <action android:name="android.intent.action.MAIN"/> <category android:name="android.intent.category.LAUNCHER"/> </intent-filter> </activity> </application> </manifest>
When we run the program, we will get output as shown above.
That’s end of our tutorial on Creating Android Floating Action Button Programmatically in Kotlin.