Create An Android ChronoMeter Programmatically in Kotlin

In this article, we will learn how to create android ChronoMeter programmatically in Kotlin. We will go through various steps that explains how to create ChronoMeter and add it in kotlin file, use different attributes to customise it etc. in any android application. For example, how to set text in ChronoMeter programmatically, how to set id of ChronoMeter, how to capitalise text of ChronoMeter dynamically etc. We will get answer to all such questions in this post.

Learn to use Different Attributes of ChronoMeter in XML File to Customize it.

Output

Tutorialwing Kotlin Dynamic ChronoMeter Output Android ChronoMeter Programmatically in kotlin

Tutorialwing Kotlin Dynamic ChronoMeter Output

Getting Started

We can define android ChronoMeter widget as below –

ChronoMeter is simple widget that can be used as simple timer. You can count up or down with a given base time using chronoMeter. If you do not provide a base time, it will assume base time as time at which you call start() method.

Now, how do we use ChronoMeter in android application ?

Creating New Project

Follow steps below to create any android project in Kotlin –

Step Description
1. Open Android Studio (Ignore if already done).
2. Go to File => New => New Project. This will open a new window. Then, under Phone and Tablet section, select Empty Activity. Then, click Next.
3. In next screen, select project name as DynamicChronoMeter. Then, fill other required details.
4. Then, clicking on Finish button creates new project.

Newbie in Android ?
Some very important concepts (Recommended to learn before you move ahead)

Before we move ahead, we need to setup for viewBinding to access ChronoMeter in Kotlin file without using findViewById() method.

Setup ViewBinding

Add viewBinding true in app/build.gradle file.

 
 android { 
 	// OTHER CODE... 
 	buildFeatures { 
 		viewBinding true 
 	} 
 } 
 

Now, set content in activity using view binding.
Open MainActivity.kt file and write below code in it.

 
 class MainActivity : AppCompatActivity() { 
 	
 	private lateinit var binding: ActivityMainBinding 
 	
 	override fun onCreate(savedInstanceState: Bundle?) { 
 		super.onCreate(savedInstanceState) 
 		binding = ActivityMainBinding.inflate(layoutInflater) 
 		val view = binding.root 
 		setContentView(view) 
 	} 
 } 
 

Now, we can access view in Kotlin file without using findViewById() method.

Since we have a new project, we will modify the xml and class file to use ChronoMeter programmatically in kotlin. Please follow the steps below.

2. Modify Values Folder

Open res/values/strings.xml file. 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>

Other values folders have not been changed. So, we are not going to mention it here.

3. Modify Layout Folder

Open res/layout/activity_main.xml file. 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/btnStart"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="20dp"
        android:paddingRight="20dp"
        android:text="@string/start"/>

</LinearLayout>

Note that LinearLayout has id rootContainer. In Kotlin file, we will create ChronoMeter Dynamically and add it into this LinearLayout having id rootContainer.

4. Create Android ChronoMeter programmatically in Kotlin

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

package com.tutorialwing.dynamicchronometer

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.view.ViewGroup
import android.widget.Chronometer
import android.widget.LinearLayout
import android.widget.Toast
import com.tutorialwing.dynamicchronometer.databinding.ActivityMainBinding

class MainActivity : AppCompatActivity() {

	private lateinit var binding: ActivityMainBinding

	override fun onCreate(savedInstanceState: Bundle?) {
		super.onCreate(savedInstanceState)
		binding = ActivityMainBinding.inflate(layoutInflater)
		val view = binding.root
		setContentView(view)

		setupChronoMeter()
	}

	private fun setupChronoMeter() {
		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

		binding.btnStart.setOnClickListener(object : View.OnClickListener {

			var isPlaying = false

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

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

		binding.rootContainer.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.

Finally, when you run the application, you will get output as shown above.

Tutorialwing Kotlin Dynamic ChronoMeter Output Android ChronoMeter Programmatically in kotlin

Tutorialwing Kotlin Dynamic ChronoMeter Output

Now, Let’s check how to use different attributes of ChronoMeter to customize it dynamically –

Set Id of ChronoMeter

Follow steps below to set id of ChronoMeter programmatically –

  • Create ids.xml file in res/values folder. Then, add below code into it –
    <?xml version="1.0" encoding="utf-8"?>
    <resources>
        <item type="id" name="chronoMeter_ID" />
    </resources>
    
  • Now, we can set id of ChronoMeter dynamically, in MainActivity.kt file, as –

    chronoMeter.id = R.id.chronoMeter_ID  // ChronoMeter
    

    Here, we have set id of ChronoMeter using property access syntax – chronoMeter.id

Learn to Set ID of ChronoMeter Using XML Attribute

Set Width and Height of ChronoMeter

We use layoutParams to set width and height of any View programmatically. In this article, we have added ChronoMeter in LinearLayout. So, we will define LayoutParams as below –

chronoMeter.layoutParams = LinearLayout.LayoutParams(
	ViewGroup.LayoutParams.WRAP_CONTENT,
	ViewGroup.LayoutParams.WRAP_CONTENT
)

Here, we have set width and height as WRAP_CONTENT. Some of possible values for width and height are –

  • WRAP_CONTENT: Sets value of width or height depending on text inside it.
  • MATCH_PARENT: Sets value of width of height depending on width or height of parent layout . i.e. width or height of ChronoMeter will be same as width or height of parent layout.
  • Fixed Value: Sets width or height as per value provided.

Learn to Set Width or Height of ChronoMeter Using XML Attribute

Set Padding of ChronoMeter

Follow steps below to set padding of ChronoMeter Dynamically –

  • If there is no dimens.xml file, create dimens.xml file in res/values folder. Then, add below code in it –
    <?xml version="1.0" encoding="utf-8"?>
    <resources>
        <dimen name="text_padding">16dp</dimen>
    </resources>
    
  • Now, we can set padding of ChronoMeter dynamically, in MainActivity.kt file, as –
    val padding = resources.getDimension(R.dimen.text_padding).toInt()
    chronoMeter.setPadding(padding, padding, padding, padding)
    

    Here, we have accessed dimension defined in dimens.xml using getDimension() method. Then, set padding of ChronoMeter using setPadding() method.

Learn to Set Padding of ChronoMeter Using XML Attribute

Set Margin of ChronoMeter

Follow steps below to set margin of ChronoMeter Dynamically –

  • If there is no dimens.xml file, create dimens.xml file in res/values folder. Then, add below code in it –
    <?xml version="1.0" encoding="utf-8"?>
    <resources>
        <dimen name="text_margin">16dp</dimen>
    </resources>
    
  • Now, we can set margin of ChronoMeter dynamically, in MainActivity.kt file, as –
    val margin = resources.getDimension(R.dimen.text_margin).toInt()
    val layoutParams = LinearLayout.LayoutParams(
    	ViewGroup.LayoutParams.WRAP_CONTENT,
    	ViewGroup.LayoutParams.WRAP_CONTENT
    )
    layoutParams.setMargins(margin, margin, margin, margin)
    chronoMeter.layoutParams = layoutParams
    

    Here, we have accessed dimension defined in dimens.xml using getDimension() method. Then, we have defined layoutParams, set margin to layoutParams. After that, set layoutParams to ChronoMeter.

Learn to Set Margin of ChronoMeter Using XML Attribute

Set Background of ChronoMeter

Follow steps below to set background of ChronoMeter programmatically –

  • If there is no colors.xml file, create colors.xml file in res/values folder. Then, add below code in it –
    <?xml version="1.0" encoding="utf-8"?>
    <resources>
        <color name="purple_200">#FFBB86FC</color>
    </resources>
    
  • Now, we can set background of ChronoMeter dynamically, in MainActivity.kt file, as –
    val color = ContextCompat.getColor(this, R.color.purple_200)
    chronoMeter.setBackgroundColor(color)
    

    Here, we used setBackgroundColor() method to set background color in chronoMeter.

Learn to Set Background of ChronoMeter Using XML Attribute

Set Visibility of ChronoMeter

We can set visibility of ChronoMeter programmatically as –

chronoMeter.visibility = View.VISIBLE

Here, we have set visibility of ChronoMeter using chronoMeter.visibility attribute. Visibility can be of three types – gone, visible and invisible.
Learn to Set Visibility of ChronoMeter Using XML Attribute

Set Text of ChronoMeter

Follow steps below to set text of ChronoMeter programmatically –

  • If there is no strings.xml file, create strings.xml file in res/values folder. Then, add below code in it –
    <resources>
        <string name="click_on_me">Click on me</string>
    </resources>
    
  • Now, we can set text of ChronoMeter dynamically, in MainActivity.kt file, as –
    chronoMeter.text = getString(R.string.click_on_me)
    

    Here, we used chronoMeter.text to set text in chronoMeter.

Learn to Set Text of ChronoMeter Using XML Attribute

Set Color of Text of ChronoMeter

Follow steps below to set color of text of ChronoMeter programmatically in Kotlin –

  • If there is no colors.xml file, create colors.xml file in res/values folder. Then, add below code in it –
    <?xml version="1.0" encoding="utf-8"?>
    <resources>
        <color name="black">#FF000000</color>
    </resources>
    
  • Now, we can set color of text of ChronoMeter dynamically, in MainActivity.kt file, as –
    val textColor = ContextCompat.getColor(this, R.color.black)
    chronoMeter.setTextColor(textColor)
    

    Here, we used setTextColor() method to set color of ChronoMeter of chronoMeter.

Learn to Set Color of ChronoMeter Using XML Attribute

Set Gravity of ChronoMeter

We can set gravity of text of ChronoMeter programmatically in Kotlin as –

chronoMeter.gravity = Gravity.CENTER

Here, we have set gravity of ChronoMeter as center. So, all the text of ChronoMeter will be center aligned.
We can also apply multiple gravity values as –

chronoMeter.gravity = Gravity.CENTER_HORIZONTAL or Gravity.BOTTOM

Here, we have applied multiple gravity values, in Kotlin, to ChronoMeter. In above case, text will be aligned as horizontally centered to bottom.
Learn to Set Margin of ChronoMeter Using XML Attribute

Set Text in Uppercase or Lowercase

Follow steps below to set text in uppercase or lowercase programmatically as –

  • Set Text in Uppercase

    We use chronoMeter.isAllCaps attributes to set text in uppercase or normal. If it is true, text will be set in uppercase.

    chronoMeter.text = "Hello Tutorialwing"
    chronoMeter.isAllCaps = true
    

    In Above case, “Hello Tutorialwing” will be set in Uppercase to ChronoMeter. So, text will be “HELLO TUTORIALWING”.

  • By default, isAllCaps is false. So, whatever is written, text will be set as it is. For example,

    chronoMeter.text = "Hello Tutorialwing"
    chronoMeter.isAllCaps = false. // By default it is false. Written here for example.
    

    Above code will set text, “Hello Tutorialwing”, to ChronoMeter without changing it to Uppercase.

    Actually, if isAllCaps is false, text is set as it is. It neither changes to uppercase nor lowercase.

    How do we set text in lowercase?

    Answer –

    • In xml file – write all the text in lowercase.
    • In kotlin file – take text as string. Then, convert it in lowercase. Then, set it to chronoMeter.

Learn to Set Text in Uppercase or Lowercase Using XML Attribute

Set Size of Text in ChronoMeter

Follow steps below to set size of ChronoMeter programmatically using chronoMeter.textSize attribute –

  • Open res/values/dimens.xml file. Then, add below font-size in it –
    <dimen name="text_size">16sp</dimen>
    
  • Now, using chronoMeter.textSize attribute, we can set size of text dynamically as –

    chronoMeter.textSize = resources.getDimension(R.dimen.text_margin)
    

Learn to Set Size of Text in ChronoMeter Using XML Attribute

Set Style (Bold/italic) of Text in ChronoMeter

We can set textStyle of ChronoMeter programmatically as –

chronoMeter.typeface = Typeface.DEFAULT_BOLD;

In above case, we have set textStyle as bold. So, text of ChronoMeter will be displayed as bold letters.

If we want to preserve previous textStyle too, we can do it as –

chronoMeter.setTypeface(chronoMeter.typeface, Typeface.BOLD);

Learn to Set Typeface of ChronoMeter Using XML Attribute

Set Letter Spacing of Text in ChronoMeter

Follow steps below to set letter spacing of ChronoMeter programmatically –

  • Open res/values/dimens.xml file. Then, add below dimension in it –
    <dimen name="text_letter_spacing">1dp</dimen>
    
  • We use chronoMeter.letterSpacing attribute to set letter spacing of ChronoMeter as below –

    chronoMeter.letterSpacing = resources.getDimension(R.dimen.text_letter_spacing)
    

Learn to Set Letter Spacing of ChronoMeter Using XML Attribute

That’s end of tutorial on ChronoMeter Programmatically in Kotlin With Example.

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