PowerWheelPicker for Android

PowerWheelPicker is a highly customizable wheel picker view for Android, backed by RecyclerView and SimpleCarousel.

Installation

To download this library, add dependency to your project.

dependencies {
    implementation("com.cheonjaeung.powerwheelpicker.android:powerwheelpicker:<version>")
}

Getting Started

Setup

Add WheelPicker view to your layout.

<com.cheonjaeung.powerwheelpicker.android.WheelPicker
    android:id="@+id/wheelPicker"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" />

All supported attributes:

Attribute	Type	Description
android:orientation	enum(horizontal, vertical)	Sets orientation of the WheelPicker.
app:circular	boolean	If true, enable circular mode.
app:selectorWidth	dimension	Size of the selector area.
app:selectorHeight	dimension	Size of the selector area.

WheelPicker needs RecyclerView.Adapter to handle data set. Create and add an adapter to WheelPicker.

val wheelPicker = findViewById<WheelPicker>(R.id.wheelPicker)
wheelPicker.adapter = SampleAdapter()

class SampleAdapter : RecyclerView.Adapter<SampleAdapter.Holder>() {
    // ...
}

Event Listening

WheelPicker supports listeners for scrolling and item selected event.

There are 2 listeners, WheelPicker.OnScrollListener and WheelPicker.OnItemSelectedListener. Both listeners can be added and removed via add or remove prefixed methods.

OnScrollListener is a listener to receive scrolling event. It is same to RecyclerView.OnScrollListener.

wheelPicker.addOnScrollListener(object : WheelPicker.OnScrollListener() {
    override fun onScrollStateChanged(wheelPicker: WheelPicker, @ScrollState newState: Int) {
        // Action for scroll state changing.
    }

    override fun onScrolled(wheelPicker: WheelPicker, dx: Int, dy: Int) {
        // Action for scrolling.
    }
})

OnItemSelectedListener is a listener to receive item selected event.

wheelPicker.addOnItemSelectedListener { _, position ->
    Snackbar.make(findViewById(R.id.main), "Selected position: $position", 1000).show()
}

Visual Effects

WheelPicker has WheelPicker.ItemEffector to support visual effects like transformation, alpha and others.

ItemEffector has 3 callbacks, applyEffectOnScrollStateChanged, applyEffectOnScrolled and applyEffectOnItemSelected. It makes more flexible to apply visual effect.

wheelPicker.addItemEffector(object : WheelPicker.ItemEffector() {
    // Implementation of custom effector.
})

Sample

This project has sample application in the sample directory. The sample app provides example of basic usage and visual effects.

Changelog

Please see changelog file.

License

Copyright 2023 Cheon Jaeung.

This project is licensed under the Apache License Version 2.0. See License file for more details.