Android set textview width programmatically

Making the most of TextView auto-sizing on Android

Dynamically adjusting the size of text on Android with a simple API

TextView auto-sizing was introduced to the framework with Android 8.0 Oreo (API 26). It offers a simple yet powerful API to solve a particular problem: scaling of text size to fit text bounds.

When is this needed? 🤔

For Android Development, using a fixed textSize , layout_width=»match_parent” and layout_height=»wrap_content” (perhaps inside a scrollable parent) is fairly common practice and suitable for most TextView use cases.

However, consider the case where the width and/or height of the text bounds are fixed and the text needs to adapt to the available space. Examples include a newspaper-style layout, a font selector that needs to show each different font typeface/name on a single-line, etc. The text can’t scroll and we can’t just add a «read more» button. In these scenarios, TextView auto-sizing is precisely what we need.

The basics 🔤

The TextView auto-sizing API is fairly concise. It can be implemented in XML layouts or programmatically. There are three distinct ways of enabling auto-sizing on a TextView , with increasing levels of specificity: Default, Granular and Preset.

At the time of this writing, the chances of anyone having a minSdk of 26 are quite slim. Thankfully, all of the auto-sizing functionality is available in the AndroidX core package (formerly Support Library). The differences to the framework API are minimal:

• Use the app namespace for XML attributes
• Use the functions in TextViewCompat instead those on TextView directly

Note: All of the examples in this post will use the AndroidX implementation.

Before we get going, there are two important points to keep in mind:

• Auto-sizing (as the name would suggest) only adjusts the text size. Other properties (eg. letterSpacing , lineHeight , etc.) are not changed. They do, of course, affect the text layout bounds and thus impact the automatic size chosen for the text.
• It is advised to not use a layout_width or layout_height of «wrap_content» when using TextView auto-sizing, as this may lead to unexpected results. Using a fixed dimension or «match_parent» is fine (or a “0dp” match_constraint if you are using ConstraintLayout ) .

Default auto-sizing 1️⃣

This is the simplest way of enabling TextView auto-sizing. Given the bounds and attributes of a TextView , the text size is adjusted in an attempt to perfectly fit the horizontal and vertical axes.

Note: The granularity dimensions for default auto-sizing are minTextSize = 12sp, maxTextSize = 112sp, and granularity = 1px (see Granular auto-sizing below).

In XML:

Programmatically:

where autoSizeTextType can be:

• TextViewCompat. AUTO_SIZE_TEXT_TYPE_UNIFORM (enabled)
• TextViewCompat. AUTO_SIZE_TEXT_TYPE_NONE (disabled)

Granular auto-sizing 2️⃣

This allows you to define the values used in uniform auto-sizing: the minimum and maximum text sizes as well a dimension for the size of each «step». A «step» is the increase/decrease in size of the text layout bounds. The text size scales uniformly between the minimum and maximum text size after each «step».

In XML:

Programmatically:

where unit is the TypedValue dimension unit of all of the configuration values (eg. TypedValue. COMPLEX_UNIT_SP ).

Preset auto-sizing 3️⃣

This allows you to specify all the possible values used for auto-sizing. The most appropriate text size will be picked from these values to fit the text bounds.

In XML:

Add the preset sizes to res/values/arrays.xml:

Programmatically:

where unit is the TypedValue dimension unit of the preset size values in the array.

Pro-tips and gotchas 🤓

Mixing value types:

You may have noticed that the programmatic versions of granular and preset auto-sizing could be limiting: the TypedValue unit in these functions applies to all of the supplied auto-sizing values. If you want to mix types (eg. PX and SP) then you need to do so in XML.

Auto-sizing to a single line:

You may be required to restrict auto-sized text to a single line. You can set the lines or maxLines TextView layout attributes to «1» (or use the programmatic equivalent). You may also need to adjust the granular autoSizeMinTextSize , as single-line text will be clipped if the minimum text size is reached but the width still exceeds that of the layout bounds.

Performance:

For performance optimization, one might assume that using preset auto-sizing is the best option. In reality, granular text sizes are precomputed given the minimum, maximum and step values and the difference is negligible.

I hope this post has provided some insight into TextView auto-sizing and how best to make use of it. If you have any questions, thoughts or suggestions then I’d love to hear from you!

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Tutorialwing

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.

Output

Tutorialwing Create TextView Programmatically Tutorial 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.

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

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.

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.

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.

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

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

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 –

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.

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 –
• Now, we can set padding of textView dynamically, in MainActivity.kt file, as –

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

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 –
• Now, we can set margin of textView dynamically, in MainActivity.kt file, as –

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.

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 –
• Now, we can set background of textView dynamically, in MainActivity.kt file, as –

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

Set Visibility of TextView

We can set visibility of textView programmatically as –

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 –
• Now, we can set text of textView dynamically, in MainActivity.kt file, as –

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

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 –
• Now, we can set color of text of textView dynamically, in MainActivity.kt file, as –

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

Set Gravity of TextView

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

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 –

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.

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,

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?

• 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.

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 –
• Now, using textView.textSize attribute, we can set size of text dynamically as –

Set Style (Bold/italic) of Text in TextView

We can set textStyle of textView programmatically as –

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 –

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 –
• We use textView.letterSpacing attribute to set letter spacing of textView as below –

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

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