In this article, we will learn how to create android Textview programmatically in Kotlin. We will go through various steps that explains how to create Textview and add it in kotlin file, use different attributes to customise it etc. in any android application. For example, how to set text in textView programmatically, how to set id of textView, how to capitalise text of textview dynamically etc. We will get answer to all such questions in this post.
Learn to use Different Attributes of TextView in XML File to Customize it.
Output
Video Output
Getting Started
We can define android Textview widget as below –
Android TextView widget is a View that are used to show texts to the user and optionally allow them to edit it. However, Text editing is disabled by default. You need to customise the basic class of TextView Widget to make it editable.
Now, how do we use TextView 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 DynamicTextView. 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 widget 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 TextView 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">DynamicTextViewUsingKotlin</string> <string name="clicked_on_me">You clicked on me.</string> <string name="click_on_me">Click on me</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 android:id="@+id/rootLayout" xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:gravity="center" android:orientation="vertical"> </LinearLayout>
Note that LinearLayout has id rootLayout. In Kotlin file, we will create TextView Dynamically and add it into this LinearLayout having id rootLayout.
4. Create Android TextView programmatically in Kotlin
Open src/main/java/com.tutorialwing.dynamictextview/MainActivity.kt file. Then, add below code into it.
package com.tutorialwing.dynamictextview import androidx.appcompat.app.AppCompatActivity import android.os.Bundle import android.view.Gravity import android.view.ViewGroup import android.widget.LinearLayout import android.widget.TextView import android.widget.Toast import com.tutorialwing.dynamictextview.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) addTextView() } private fun addTextView() { // Create TextView programmatically. val textView = TextView(this) textView.layoutParams = LinearLayout.LayoutParams( ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT ) textView.gravity = Gravity.CENTER textView.text = getString(R.string.click_on_me) // Add TextView to LinearLayout binding.rootLayout.addView(textView) } }
Note that we are creating TextView dynamically. Then, we have added it’s layoutParams, gravity and text dynamically. Finally, added this TextView in LinearLayout having id rootLayout.
Finally, when you run the application, you will get output as shown above.
Now, Let’s check how to use different attributes of textView to customize it dynamically –
Set Id of TextView
Follow steps below to set id of textView 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="TEXT_ID" /> </resources>
-
Now, we can set id of textView dynamically, in MainActivity.kt file, as –
textView.id = R.id.TEXT_ID
Here, we have set id of textView using property access syntax – textView.id
Learn to Set ID of TextView Using XML Attribute
Set Width and Height of TextView
We use layoutParams to set width and height of any View programmatically. In this article, we have added textView in LinearLayout. So, we will define LayoutParams as below –
textView.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 textView 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 TextView Using XML Attribute
Set Padding of TextView
Follow steps below to set padding of textView 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 textView dynamically, in MainActivity.kt file, as –
val padding = resources.getDimension(R.dimen.text_padding).toInt() textView.setPadding(padding, padding, padding, padding)
Here, we have accessed dimension defined in dimens.xml using getDimension() method. Then, set padding of textView using setPadding() method.
Learn to Set Padding of TextView Using XML Attribute
Set Margin of TextView
Follow steps below to set margin of textView 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 textView 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) textView.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 textView.
Learn to Set Margin of TextView Using XML Attribute
Set Background of TextView
Follow steps below to set background of textView 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 textView dynamically, in MainActivity.kt file, as –
val color = ContextCompat.getColor(this, R.color.purple_200) textView.setBackgroundColor(color)
Here, we used setBackgroundColor() method to set background color in textView.
Learn to Set Background of TextView Using XML Attribute
Set Visibility of TextView
We can set visibility of textView programmatically as –
textView.visibility = View.VISIBLE
Here, we have set visibility of textView using textView.visibility attribute. Visibility can be of three types – gone, visible and invisible.
Learn to Set Visibility of TextView Using XML Attribute
Set Text of TextView
Follow steps below to set text of textView 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 textView dynamically, in MainActivity.kt file, as –
textView.text = getString(R.string.click_on_me)
Here, we used textView.text to set text in textView.
Learn to Set Text of TextView Using XML Attribute
Set Color of Text of TextView
Follow steps below to set color of text of textView 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 textView dynamically, in MainActivity.kt file, as –
val textColor = ContextCompat.getColor(this, R.color.black) textView.setTextColor(textColor)
Here, we used setTextColor() method to set color of textView of textView.
Learn to Set Color of TextView Using XML Attribute
Set Gravity of TextView
We can set gravity of text of textView programmatically in Kotlin as –
textView.gravity = Gravity.CENTER
Here, we have set gravity of textView as center. So, all the text of textView will be center aligned.
We can also apply multiple gravity values as –
textView.gravity = Gravity.CENTER_HORIZONTAL or Gravity.BOTTOM
Here, we have applied multiple gravity values, in Kotlin, to textView. In above case, text will be aligned as horizontally centered to bottom.
Learn to Set Margin of TextView 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 textView.isAllCaps attributes to set text in uppercase or normal. If it is true, text will be set in uppercase.
textView.text = "Hello Tutorialwing" textView.isAllCaps = true
In Above case, “Hello Tutorialwing” will be set in Uppercase to textView. So, text will be “HELLO TUTORIALWING”.
-
By default, isAllCaps is false. So, whatever is written, text will be set as it is. For example,
textView.text = "Hello Tutorialwing" textView.isAllCaps = false. // By default it is false. Written here for example.
Above code will set text, “Hello Tutorialwing”, to TextView 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 textView.
Learn to Set Text in Uppercase or Lowercase Using XML Attribute
Set Size of Text in TextView
Follow steps below to set size of textView programmatically using textView.textSize attribute –
- Open res/values/dimens.xml file. Then, add below font-size in it –
<dimen name="text_size">16sp</dimen>
-
Now, using textView.textSize attribute, we can set size of text dynamically as –
textView.textSize = resources.getDimension(R.dimen.text_margin)
Learn to Set Size of Text in TextView Using XML Attribute
Set Style (Bold/italic) of Text in TextView
We can set textStyle of textView programmatically as –
textView.typeface = Typeface.DEFAULT_BOLD;
In above case, we have set textStyle as bold. So, text of textView will be displayed as bold letters.
If we want to preserve previous textStyle too, we can do it as –
textView.setTypeface(textView.typeface, Typeface.BOLD);
Learn to Set Typeface of TextView Using XML Attribute
Set Letter Spacing of Text in TextView
Follow steps below to set letter spacing of textView programmatically –
- Open res/values/dimens.xml file. Then, add below dimension in it –
<dimen name="text_letter_spacing">1dp</dimen>
-
We use textView.letterSpacing attribute to set letter spacing of textView as below –
textView.letterSpacing = resources.getDimension(R.dimen.text_letter_spacing)
Learn to Set Letter Spacing of TextView Using XML Attribute
That’s end of tutorial on textView Programmatically in Kotlin With Example.
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