In this article, we will learn how to create android Filter Chip programmatically in Kotlin. We will go through various steps that explains how to create Filter Chip and add it in kotlin file, use different attributes to customise it etc. in any android application.

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

Output

Getting Started

We can define android Filter Chip widget as below –

Filter Chips are used to display filter for a collection. It is a good collection alternative to toggle button or checkboxes.

Now, how do we use Filter Chip in android application ?

Before we move ahead, we need to setup for viewBinding to access Filter Chip 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 Filter Chip 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">DynamicChipFilter</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"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
    android:padding="10dp"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/label"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="20dp"
        android:text="Choose Amenities"
        android:textSize="16sp"
        android:textStyle="bold"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <com.google.android.material.chip.ChipGroup
        android:id="@+id/chipGroup"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/label"
        app:singleLine="false">

    </com.google.android.material.chip.ChipGroup>

</androidx.constraintlayout.widget.ConstraintLayout>

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

4. Create XML file for Filter Chip

Create a new file, chip.xml, in res/layout folder. Then, add below code into it –

<?xml version="1.0" encoding="utf-8"?>
<com.google.android.material.chip.Chip xmlns:android="http://schemas.android.com/apk/res/android"
    style="@style/Widget.MaterialComponents.Chip.Filter"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

We will use this chip to dynamically inflate it in MainActivity file.

5. Create Android Filter Chip programmatically in Kotlin

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

package com.tutorialwing.dynamicchipfilter

import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import com.google.android.material.chip.Chip
import com.tutorialwing.dynamicchipfilter.databinding.ActivityMainBinding
import com.tutorialwing.dynamicchipfilter.databinding.ChipBinding

class MainActivity : AppCompatActivity() {

	private lateinit var binding: ActivityMainBinding

	override fun onCreate(savedInstanceState: Bundle?) {
		super.onCreate(savedInstanceState)

		binding = ActivityMainBinding.inflate(layoutInflater)
		setContentView(binding.root)

		setupChip()
	}

	private fun setupChip() {
		val nameList =
			arrayListOf("Elevator", "Washer / Dryer", "Fireplace", "Wheelchair Access", "Dogs OK")
		for (name in nameList) {
			val chip = createChip(name)
			binding.chipGroup.addView(chip)
		}
	}

	private fun createChip(label: String): Chip {
		val chip = ChipBinding.inflate(layoutInflater).root
		chip.text = label
		return chip
	}
}

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

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

Set Id of Filter Chip

Follow steps below to set id of Filter Chip 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="filerChip_ID" />
  </resources>
  

• Now, we can set id of Filter Chip dynamically, in MainActivity.kt file, as –

  filterChip.id = R.id.filerChip_ID  // Filter Chip
  

  Here, we have set id of Filter Chip using property access syntax – filterChip.id

Learn to Set ID of Filter Chip Using XML Attribute

Set Width and Height of Filter Chip

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

filterChip.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 Filter Chip 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 Filter Chip Using XML Attribute

Set Padding of Filter Chip

Follow steps below to set padding of Filter Chip 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 Filter Chip dynamically, in MainActivity.kt file, as –

  val padding = resources.getDimension(R.dimen.text_padding).toInt()
  filterChip.setPadding(padding, padding, padding, padding)
  

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

Learn to Set Padding of Filter Chip Using XML Attribute

Set Margin of Filter Chip

Follow steps below to set margin of Filter Chip 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 Filter Chip 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)
  filterChip.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 Filter Chip.

Learn to Set Margin of Filter Chip Using XML Attribute

Set Background of Filter Chip

Follow steps below to set background of Filter Chip 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 Filter Chip dynamically, in MainActivity.kt file, as –

  val color = ContextCompat.getColor(this, R.color.purple_200)
  filterChip.setBackgroundColor(color)
  

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

Learn to Set Background of Filter Chip Using XML Attribute

Set Visibility of Filter Chip

We can set visibility of Filter Chip programmatically as –

filterChip.visibility = View.VISIBLE

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

That’s end of tutorial on Android Filter Chip Programmatically in Kotlin With Example.