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Android ScrollView and HorizontalScrollView Tutorial with Examples

  1. ScrollView and HorizontalScrollView
  2. An example of the ScrollView
  3. An example of the HorizontalScrollView

1. ScrollView and HorizontalScrollView

In Android, ScrollView is a Layout type, which is a rectangular container with a vertical scroll bar. It is able to contain another component larger-sized than itself. Similar to ScrollView, HorizontalScrollView is a container with a horizontal scroll bar.
Generally speaking, ScrollView and HorizontalScrollView are useful. Both of them are used to contain a large-sized content, and the user needs to use scroll bars to be able to view the content completely.
ScrollView and HorizontalScrollView can only contain one direct child component, so its child component is normally another container that can contain one or more child components.
On Android Studio, if you drag and drop a ScrollView (Or HorizontalScrollView) into the interface, a child component called LinearLayout will automatically be added. You can definitely delete it to insert another child component.
You had better not combine the ScrollView with ListView or GridView components, because both of them already have their own vertical scroll bars.

2. An example of the ScrollView

In this example, a vertical LinearLayout has multiple child components. As clearly seen, it needs a space with sufficient height. However, the screen size is limited, so it is essential to be placed in a ScrollView.
Some steps to design the interface of the app are shown in this example:
Set ID, Text for the components in the interface:
main_activity.xml
<?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"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/button_scrollUp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginTop="24dp"
        android:text="Scroll Up"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/button_scrollDown"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="19dp"
        android:layout_marginLeft="19dp"
        android:layout_marginTop="24dp"
        android:text="Scroll Down"
        app:layout_constraintStart_toEndOf="@+id/button_scrollUp"
        app:layout_constraintTop_toTopOf="parent" />

    <ScrollView
        android:id="@+id/scrollView"
        android:layout_width="0dp"
        android:layout_height="229dp"
        android:layout_marginStart="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginTop="16dp"
        android:layout_marginEnd="16dp"
        android:layout_marginRight="16dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button_scrollUp">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <Button
                android:id="@+id/button11"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button" />

            <Button
                android:id="@+id/button10"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button" />

            <Button
                android:id="@+id/button9"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button" />

            <Button
                android:id="@+id/button8"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button" />

            <Button
                android:id="@+id/button7"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button" />

            <Button
                android:id="@+id/button6"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button" />

            <Button
                android:id="@+id/button5"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button" />

            <Button
                android:id="@+id/button4"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button" />

            <Button
                android:id="@+id/button3"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button" />
        </LinearLayout>
    </ScrollView>
</androidx.constraintlayout.widget.ConstraintLayout>
MainActivity.java
package com.example.scrollviewexample;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ScrollView;

public class MainActivity extends AppCompatActivity {

    private ScrollView scrollView;

    private Button buttonScrollUp;
    private Button buttonScrollDown;

    public static final int SCROLL_DELTA = 15; // Pixel.

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        this.scrollView = (ScrollView) this.findViewById(R.id.scrollView);

        this.buttonScrollUp = (Button) this.findViewById(R.id.button_scrollUp);
        this.buttonScrollDown = (Button) this.findViewById(R.id.button_scrollDown);

        this.buttonScrollUp.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                doScrollUp();
            }
        });

        this.buttonScrollDown.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                doScrollDown();
            }
        });
    }

    private void doScrollUp() {

        int x = this.scrollView.getScrollX();
        int y = this.scrollView.getScrollY();

        if(y - SCROLL_DELTA >= 0) {
            this.scrollView.scrollTo(x, y-SCROLL_DELTA);
        }

    }

    private void doScrollDown() {
        int maxAmount = scrollView.getMaxScrollAmount();

        int x = this.scrollView.getScrollX();
        int y = this.scrollView.getScrollY();

        if(y + SCROLL_DELTA <= maxAmount) {
            this.scrollView.scrollTo(x, y + SCROLL_DELTA);
        }
    }
}

3. An example of the HorizontalScrollView

In this example, a horizontal LinearLayout has a lot of child components. It definitely needs a space with sufficient width. As you can see, the user's device screen size is limited, so it is necessary to be placed in a HorizontalScrollView.
Now let's design your interface:
And set ID, Text for the components in the interface:
activity_main.xml
<?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"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/button_scrollLeft"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginTop="24dp"
        android:text="Scroll Left"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/button_scrollRight"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginTop="24dp"
        android:text="Scroll Right"
        app:layout_constraintStart_toEndOf="@+id/button_scrollLeft"
        app:layout_constraintTop_toTopOf="parent" />

    <HorizontalScrollView
        android:id="@+id/horizontalScrollView"
        android:layout_width="0dp"
        android:layout_height="128dp"
        android:layout_marginStart="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginTop="16dp"
        android:layout_marginEnd="16dp"
        android:layout_marginRight="16dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button_scrollLeft">

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:orientation="horizontal">

            <Button
                android:id="@+id/button9"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="Button" />

            <Button
                android:id="@+id/button8"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="Button" />

            <Button
                android:id="@+id/button7"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="Button" />

            <Button
                android:id="@+id/button6"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="Button" />

            <Button
                android:id="@+id/button5"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="Button" />

            <Button
                android:id="@+id/button4"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="Button" />

            <Button
                android:id="@+id/button3"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="Button" />
        </LinearLayout>
    </HorizontalScrollView>
</androidx.constraintlayout.widget.ConstraintLayout>
MainActivity.java
package com.example.horizontalscrollviewexample;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.HorizontalScrollView;

public class MainActivity extends AppCompatActivity {

    private HorizontalScrollView horizontalScrollView;

    private Button buttonScrollLeft;
    private Button buttonScrollRight;

    public static final int SCROLL_DELTA = 15; // Pixel.

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        this.horizontalScrollView = (HorizontalScrollView) this.findViewById(R.id.horizontalScrollView);

        this.buttonScrollLeft = (Button) this.findViewById(R.id.button_scrollLeft);
        this.buttonScrollRight = (Button) this.findViewById(R.id.button_scrollRight);

        this.buttonScrollLeft.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                doScrollLeft();
            }
        });

        this.buttonScrollRight.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                doScrollRight();
            }
        });
    }

    private void doScrollLeft() {

        int x = this.horizontalScrollView.getScrollX();
        int y = this.horizontalScrollView.getScrollY();

        if(x - SCROLL_DELTA >= 0) {
            this.horizontalScrollView.scrollTo(x - SCROLL_DELTA, y);
        }

    }

    private void doScrollRight() {
        int maxAmount = horizontalScrollView.getMaxScrollAmount();

        int x = this.horizontalScrollView.getScrollX();
        int y = this.horizontalScrollView.getScrollY();

        if(x + SCROLL_DELTA <= maxAmount) {
            this.horizontalScrollView.scrollTo(x + SCROLL_DELTA, y);
        }
    }
}

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