Scrolling Image View

An Android view for displaying repeated continuous side scrolling images. This can be used to create a parallax animation effect.

Example

Installation

Step 1. Add the JitPack repository to your project build.gradle file

allprojects {
    repositories {
        // ~~~
        maven { url 'https://jitpack.io' }
    }
}

Step 2. Add the dependency in the form

dependencies {
    implementation 'com.github.Q42:AndroidScrollingImageView:1.3.4'
}

Sample app

Please see the sample app for some examples

Usage

In your Android layout file add:

<com.q42.android.scrollingimageview.ScrollingImageView
    android:id="@+id/scrolling_background"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    scrolling_image_view:speed="60dp"
    scrolling_image_view:contiguous="false"
    scrolling_image_view:source="@drawable/scrolling_background" />

There are three attributes for the ScrollingImageView:

• speed is the number of dp's to move the drawable per second (may be a negative number)

• source is the drawable to paint. May refer to an array of drawables

• contiguous When source is an array of drawables, contiguous determines their ordering.

  false (default) for random ordering, true for the same order as in the array

Don't forget to add the namespace to your root XML element

xmlns:scrolling_image_view="http://schemas.android.com/apk/res-auto"

In your Java code, you can start and stop the animation like this:

ScrollingImageView scrollingBackground = (ScrollingImageView) loader.findViewById(R.id.scrolling_background);
scrollingBackground.stop();
scrollingBackground.start();

Parallax effect

In order to achieve a parallax effect, you can stack multiple ScrollingImageView's in a FrameLayout with different speeds. For example:

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

  <com.q42.android.scrollingimageview.ScrollingImageView
      android:id="@+id/scrolling_background"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      scrolling_image_view:speed="60dp"
      scrolling_image_view:source="@drawable/scrolling_background" />
      
  <com.q42.android.scrollingimageview.ScrollingImageView
      android:id="@+id/scrolling_foreground"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      scrolling_image_view:speed="150dp"
      scrolling_image_view:source="@drawable/scrolling_foreground" />
</FrameLayout>