Hello Readers! In this post, we are going to learn about how to use android chronoMeter programmatically in kotlin in the application. We will also learn how to add chronoMeter to linearLayout programmatically in android application.

Output

Tutorialwing Kotlin Dynamic ChronoMeter Output

Getting Started

At first, we will create android project. Then, we will create and use chronoMeter 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.

Now, we will modify xml and kotlin file to use chronoMeter dynamically.

2. Modify Values Folder

Open res/values/strings.xml file. Then, add below code into it.

<resources>
	<string name="app_name">DynamicChronometer</string>
	<string name="stop">Stop</string>
	<string name="start">Start</string>
	<string name="playing">Playing…</string>
	<string name="stopped">Stopped…</string>
</resources>

3. Modify Layout Folder

Open res/layout/activity_main.xml file. Then, add below code into it.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
	xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="match_parent"
	android:layout_height="match_parent"
	android:orientation="vertical"
	android:padding="20dp">

	<LinearLayout
		android:id="@+id/rootContainer"
		android:layout_width="match_parent"
		android:layout_height="wrap_content"
		android:orientation="vertical">
	</LinearLayout>

	<Button
		android:id="@+id/button"
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:paddingLeft="20dp"
		android:paddingRight="20dp"
		android:text="@string/start"/>

</LinearLayout>

In activity_main.xml file, we have defined button and linearLayout, with id rootContainer, that will as container for the chronoMeter widget created programmatically in the kotlin application.

4. Create Android ChronoMeter Programmatically / Dynamically in Kotlin

Open app/src/main/java/com.tutorialwing.dynamicchronometer/MainActivity.kt file. Then, add below code into it.

package com.tutorialwing.dynamicchronometer

import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import android.view.View
import android.view.ViewGroup
import android.widget.Button
import android.widget.Chronometer
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 chronometer = Chronometer(this)
        val layoutParams = LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT)
        layoutParams.setMargins(0, 40, 0, 40)
        chronometer.layoutParams = layoutParams

        val button = findViewById<Button>(R.id.button)
        button?.setOnClickListener(object : View.OnClickListener {

            internal var isPlaying = false

            override fun onClick(v: View) {
                if (!isPlaying) {
                    chronometer.start()
                    isPlaying = true
                } else {
                    chronometer.stop()
                    isPlaying = false
                }

                button.setText(if (isPlaying) R.string.start else R.string.stop)
                Toast.makeText(this@MainActivity, getString(if (isPlaying) R.string.playing else R.string.stopped), Toast.LENGTH_SHORT).show()
            }
        })

        val linearLayout = findViewById<LinearLayout>(R.id.rootContainer)
        linearLayout?.addView(chronometer)
    }
}

We have created chronoMeter programmatically in kotlin file (i.e. MainActivity.kt file) in the application. Then, we have set layout params, margins etc. in it. After that, we have set click listener in button to play/pause the chronoMeter. We are also showing a message, as toast, that display the current status of the chronoMeter whether it is playing or paused. At last, we have added this chronoMeter in linearLayout. Similarly, you can add chronoMeter in other layouts such as RelativeLayout, FrameLayout etc.

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.dynamicchronometer"
		  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 ChronoMeter Programmatically in Kotlin.