Scroll android studio kotlin

ScrollView и HorizontalScrollView

При большом количестве информации, которую нужно поместить на экране приходится использовать полосы прокрутки. В Android существуют специальные компоненты ScrollView и HorizontalScrollView, которые являются контейнерными элементами и наследуются от ViewGroup. Обратите внимание, что класс TextView использует свою собственную прокрутку и не нуждается в добавлении отдельных полос прокрутки. Но использование отдельных полос даже с TextView может улучшить вид вашего приложения и повышает удобство работы для пользователя.

На панели инструментов компоненты можно найти в разделе Containers.

В контейнеры ScrollView и HorizontalScrollView можно размещать только один дочерний элемент (обычно LinearLayout), который в свою очередь может быть контейнером для других элементов. Виджет ScrollView, несмотря на свое название, поддерживает только вертикальную прокрутку, поэтому для создания вертикальной и горизонтальной прокрутки необходимо использовать ScrollView в сочетании с HorizontalScrollView. Обычно ScrollView используют в качестве корневого элемента, а HorizontalScrollView в качестве дочернего. Можно и наоборот, пробуйте.

В в теле метода onCreate() создайте ссылку на элемент TextView, объявленный в XML-разметке, и запишите в него через метод setText() какой-нибуль длинный текст, который не поместится в видимые размеры экрана устройства:

Запустив проект, вы должны увидеть вертикальную и горизонтальную полосы прокрутки при попытке скролирования.

Если полосы прокрутки вас раздражают, то используйте атрибут android:scrollbars=»none», который скроет их.

По такому же принципу можете вложить ImageView, чтобы просматривать большие картинки:

Методы scrollBy() и scrollTo()

Вы можете программно прокручивать контент с помощью методов scrollBy() и scrollTo(). Например, можно организовать автоматическую прокрутку во время чтения. В нашем примере мы будем прокручивать контент с помощью трёх кнопок.

Сам код для методов:

Дополнительное чтение

Библиотека ParallaxScrollView с использованием эффекта параллакса. Вы прокручиваете длинный текст, а задний фон прокручивается чуть медленнее. Возможно, кому-то пригодится. Там же можно скачать готовое демо и просмотреть в действии.

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Tutorialwing

In this article, we will learn about android ScrollView using Kotlin. We will go through various example that demonstrates how to use different attributes of ScrollView. For example,

In this article, we will get answer to questions like –

• What is ScrollView?
• Why should we consider ScrollView while designing ui for any app?
• What are possibilities using ScrollView while designing ui? etc.

Let’s have a quick demo of things we want to cover in this tutorial –

Output

Tutorialwing Kotlin ScrollView Output

Tutorialwing Kotlin ScrollView Output

Getting Started

We can define android ScrollView widget as below –

ScrollView is a widget that are used to define vertically scrollable views. It can have only one direct child. So, if you need multiple child views, create a viewGroup as direct child of scrollView. Then, define all the views inside this viewGroup.

Now, how do we use ScrollView in android application ?

Creating New Project

At first, we will create an application.
So, 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 ScrollView. Then, fill other required details.
4.	Then, clicking on Finish button creates new project.

Some very important concepts (Recommended to learn before you move ahead)

Before we move ahead, we need to setup for viewBinding to access Android ScrollView Using 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.

Using ScrollView in Kotlin

Follow steps below to use ScrollView in newly created project –

• We need some images, stored in res/drawable folder, to be used in the application. These drawable images will be used by child view of scrollView to create different views.
• Open res/values/strings.xml file. Then, add below code into it.
• Open res/layout/activity_main.xml file. Then, add below code in it –
• We can also access it in Kotlin File, MainActivity.kt, as below –

Now, run the application. We will get output as below –

Tutorialwing Kotlin ScrollView Output

Tutorialwing Kotlin ScrollView Output

Different Attributes of ScrollView in XML

Now, we will see how to use different attributes of Android ScrollView using Kotlin to customise it –

Set Id of ScrollView

Many a time, we need id of View to access it in kotlin file or create ui relative to that view in xml file. So, we can set id of ScrollView using android:id attribute like below –

Here, we have set id of ScrollView as scrollView_ID using android:id=”” attribute. So, if we need to reference this ScrollView, we need to use this id – scrollView_ID.
Learn to Set ID of ScrollView Dynamically

Set Width of ScrollView

We use android:layout_width=”” attribute to set width of ScrollView.
We can do it as below –

Width can be either “MATCH_PARENT” or “WRAP_CONTENT” or any fixed value (like 20dp, 30dp etc.).
Learn to Set Width of ScrollView Dynamically

Set Height of ScrollView

We use android:layout_height=”” attribute to set height of ScrollView.
We can do it as below –

Height can be either “MATCH_PARENT” or “WRAP_CONTENT” or any fixed value.
Learn to Set Height of ScrollView Dynamically

Set Padding of ScrollView

We use android:padding=”” attribute to set padding of ScrollView.
We can do it as below –

Here, we have set padding of 10dp in ScrollView using android:padding=”” attribute.
Learn to Set Padding of ScrollView Dynamically

Set Margin of ScrollView

We use android:layout_margin=”” attribute to set margin of ScrollView.
We can do it as below –

Here, we have set margin of 10dp in ScrollView using android:layout_margin=”” attribute.
Learn to Set Margin of ScrollView Dynamically

Set Background of ScrollView

We use android:background=”” attribute to set background of ScrollView.
We can do it as below –

Here, we have set background of color #ff0000 in ScrollView using android:background=”” attribute.
Learn to Set Background of ScrollView Dynamically

Set Visibility of ScrollView

We use android:visibility=”” attribute to set visibility of ScrollView.
We can do it as below –

Here, we have set visibility of ScrollView using android:visiblity=”” attribute. Visibility can be of three types – gone, visible and invisible
Learn to Set Visibility of ScrollView Dynamically

Till now, we have see how to use android ScrollView using Kotlin. We have also gone through different attributes of ScrollView to perform certain task. Let’s have a look at list of such attributes and it’s related task.

Different Attributes of Android ScrollView Widget

Below are the various attributes that are used to customise android ScrollView Widget. However, you can check the complete list of attributes of ScrollView in it’s official documentation site. Here, we are going to list some of the important attributes of this widget –

Some of the popular attributes of android scrollView widget are –

Sr.	XML Attributes	Description
1	android:fillViewport	Defines whether scrollView should stretch it’s content to fill the viewport

Some of the popular attributes of android ScrollView inherited from FrameLayout are –

Sr.	XML Attributes	Description
1	android:foregroundGravity	Defines gravity of the foreground drawable
2	android:measureAllChildren	Defines whether to measure all children or only those in VISIBLE or INVISIBLE state when measuring

Some of the popular attributes of ScrollView inherited from ViewGroup are –

Sr.	XML Attributes	Description
1	android:animateLayoutChanges	Defines whether LayoutTransition should run whenever there is any changes in layout
2	android:animationCache	Defines whether layout animations should create a drawing cache for their children.
3	android:clipToPadding	Defines whether the ViewGroup will clip its children and resize (but not clip) any EdgeEffect to its padding, if padding is not zero.
4	android:layoutAnimation	Defines the layout animation to use the first time the ViewGroup is laid out
5	android:layoutMode	Defines the layout mode of this viewGroup

Some of the popular attributes of android ScrollView inherited from View are –

Sr.	XML Attributes	Description
1	android:alpha	Defines the alpha of the view
2	android:background	Defines the background of the view
3	android:padding	Defines padding of the view for all edges
4	android:tooltipText	Defines text displayed in a small popup window on hover or long press
5	android:clickable	Defines whether view is clickable or not
6	android:theme	Defines a theme override for view
7	android:id	Defines id of the view
8	android:padding	Defines padding of the view

We have seen different attributes of ScrollView and how to use it. If you wish to visit post to learn more about it

Thus, we have seen what is ScrollView, how can we use android ScrollView using Kotlin ? etc. We also went through different attributes of android ScrollView.

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HorizontalScrollView Android Kotlin | Step By Step Example

In this Kotlin Scrollview tutorial, I will tell you how to use HorizontalScrollView in your Android Applications. This is a step-by-step guide of HorizontalScrollview in Kotlin language. So, let’s start making HorizontalScrollView In Android Kotlin.

HorizontalScrollView Android Kotlin

I assume you have some KOTLIN skills.

1- Start a new Android Studio Project. Name it “KotlinHorizontalScrollView” or any name of your choice.

2- After your project starts you will have two files. MainActivity.kt file and activity_main_xml file.

Android Horizontal Scrollview

activity_main .xml

3- Come to the activity_main.xml file and change the default Layout from Constraint Layout to RelativeLayout.

4- So give android:gravity=”center” to the parent RelativeLayout. Then, add a HorizontalScrollView and a Linear Layout into your RelativeLayout like this.

5- Since the LinearLayout must be inside the HorizontalScrollView. So, the final activity_main.xml file will be like this.

6- Now, go to the res folder in your Android Studio list on the left and then click new and select Layout Resource File. Then give the name “test” to your new Layout XML file. After that in this file, we will design the view of our single item in the HorizontalScrollView.

HorizontalScrollView Android Kotlin ( test.xml file )

test.xml

7- Change the default Layout from Constraint Layout to Relative Layout. Then, add an ImageView and a TextView. Because we have to give some properties to our Views like this.

8- First change the gravity of the Parent RelativeLayout to android:gravity=” center”. So, the final text.xml file will be like this.

Android Horizontal Scrollview

MainActivity.kt file

9- In your MainActivity.kt file you need to add some images first. Add some random images into your “drawable” folder. In my case, I have used 10 Vector Images. To create a Vector image Right Click on your “drawable” folder then click “New” and then click “Vector Asset”

10- In the Vector Asset window you will see a small Clip Art image under Name. Click on that image and after that, you will see a list of icons. So, select the icon of your choice and change its name then save it. Then repeat the same procedure to add as many icons in your drawable folder.

11- Define an array for Names and another array for Images. Also, we will use a LinearLayout to display our View. Take these variables on the class level like this.

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