Creates effect such as vertical parallax, horizontal parallax etc. on android ImageView when it's being vertically or horizontally scrolled (moving) on the screen.

References:

• https://abdularis.com/2018/06/06/scroll_parallax_image_view.html
• https://medium.com/@abdularis/android-custom-view-tutorial-scroll-parallax-image-view-2140ac292ecb

Screenshot

Setup

• Step 1 Add repository into root build.gradle

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

• Step 2 Add library dependency into app build.gradle

dependencies {
    implementation 'com.github.abdularis:parallaximageview:1.1'
}

Usage

• Create vertical parallax image view

  <com.github.abdularis.piv.VerticalScrollParallaxImageView
  android:id="@+id/image_view"
  android:layout_width="200dp"
  android:layout_height="170dp"
  android:src="@drawable/img1"/>
  

• Create Horizontal parallax image view

  <com.github.abdularis.piv.HorizontalScrollParallaxImageView
  android:id="@+id/image_view"
  android:layout_width="200dp"
  android:layout_height="170dp"
  android:src="@drawable/img1"/>
  

• Create and customize effect on your own

  <com.github.abdularis.piv.ScrollTransformImageView
  android:id="@+id/image_view"
  android:layout_width="200dp"
  android:layout_height="170dp"
  android:src="@drawable/img1"/>
  

In the java/kotlin code you can set the effect (transformer) manually. There are three built-in effect classes, VerticalParallaxTransformer, HorizontalParallaxTransformer, HorizontalScaleTransformer.

Java code

ScrollTransformImageView img = findViewById(R.id.image_view);

// create horizontal scale effect
img.setViewTransformer(new HorizontalScaleTransformer())

// create vertical or horizontal parallax effect manually
// img.setViewTransformer(new VerticalParallaxTransformer())
// img.setViewTransformer(new HorizontalParallaxTransformer())
//
// the VerticalParallaxImageView or HorizontalParallaxImageView are nothing but the ScrollTransformImageView with coresponding parallax effect

You can create your own custom effect by extending ViewTransformer.

public class CustomTransformer extends ViewTransformer {
    @Override
    public void onAttached(@NotNull ScrollTransformImageView view) {
        // do something when this transformer is set into image view
    }

    @Override
    public void onDetached(@NotNull ScrollTransformImageView view) {
        // do something when this transformer is remove from image view
    }

    @Override
    public void apply(@NotNull ScrollTransformImageView view, @NotNull Canvas canvas, int viewX, int viewY) {
        // do transformation effect or so, this would be called everytime image view move/scrolled
    }
}

License

MIT License