Wallpaper

안드로이드에서 간단한 Wallpaper를 만들어보는 예제입니다.

AndroidManifest.xml

먼저 다음 Permission을 추가해줍니다.

    <uses-permission android:name="android.permission.SET_WALLPAPER" />
    <uses-feature
            android:name="android.software.live_wallpaper"
            android:required="true"/>

그리고 Wallpaper는 android.service를 사용하기 때문에 service도 등록합니다.

    <service
        android:name=".service.snowdeer.SimpleWallpaperService"
        android:enabled="true"
        android:label="@string/app_name"
        android:permission="android.permission.BIND_WALLPAPER">
        <intent-filter>
            <action android:name="android.service.wallpaper.WallpaperService" />
        </intent-filter>

        <meta-data
            android:name="android.service.wallpaper"
            android:resource="@xml/wallpaper" />
    </service>

BaseWallpaperService.kt

import android.content.Context
import android.service.wallpaper.WallpaperService
import android.view.MotionEvent
import android.view.SurfaceHolder
import android.view.WindowManager

interface InteractiveEngine {
    fun setScreenSize(width: Int, height: Int)
    fun onSurfaceCreated(holder: SurfaceHolder)
    fun onDestory()
}

open abstract class BaseWallpaperService : WallpaperService() {

    abstract fun handleScreenSize(width: Int, height: Int)
    abstract fun handleSurfaceCreated(holder: SurfaceHolder)
    open fun handleTouchEvent(event: MotionEvent) {}

    override fun onCreate() {
        super.onCreate()

        val window = getSystemService(Context.WINDOW_SERVICE) as WindowManager
        val display = window.defaultDisplay
        val width = display.width
        val height = display.height

        handleScreenSize(width, height)
    }

    override fun onCreateEngine(): Engine {
        return WallpaperEngine()
    }

    inner class WallpaperEngine : WallpaperService.Engine() {
        override fun onSurfaceCreated(holder: SurfaceHolder) {
            handleSurfaceCreated(holder)
        }

        override fun onTouchEvent(event: MotionEvent?) {
            event?.let {
                handleTouchEvent(event)
            }
        }
    }
}

SimpleWallpaper.kt

import android.view.MotionEvent
import android.view.SurfaceHolder
import com.snowdeer.wallpaper.service.BaseWallpaperService

class SimpleWallpaper : BaseWallpaperService() {
    val engine: InteractiveEngine = RandomColorEngine()
    
    companion object {
        const val TAG = "NormalWallpaperService"
    }

    override fun handleScreenSize(width: Int, height: Int) {
        engine.setScreenSize(width, height)
    }

    override fun handleSurfaceCreated(holder: SurfaceHolder) {
        engine.onSurfaceCreated(holder)
    }

    override fun handleTouchEvent(event: MotionEvent) {
        engine.handleTouchEvent(event)
    }

    override fun onDestroy() {
        super.onDestroy()
        engine.onDestory()
    }
}

RandomColorEngine.kt

import android.graphics.Color
import android.graphics.Paint
import android.os.Handler
import android.os.Looper
import android.view.SurfaceHolder
import com.snowdeer.service.InteractiveEngine
import kotlin.random.Random

class RandomColorEngine : InteractiveEngine {
    private val handler = Handler(Looper.getMainLooper())
    private var isRunning = false

    override fun setScreenSize(width: Int, height: Int) {

    }

    override fun onSurfaceCreated(holder: SurfaceHolder) {
        isRunning = true

        drawCanvas(holder)
    }

    override fun onDestory() {
        isRunning = false
    }

    private fun drawCanvas(holder: SurfaceHolder) {
        if (!isRunning) {
            return
        }

        try {
            val canvas = holder.lockCanvas()

            canvas?.let {
                val paint = Paint().apply {
                    val randomColor = Random.nextInt(16_777_216)
                        .toString(16)
                        .padStart(6, '0')
                    color = Color.parseColor("#$randomColor")
                    style = Paint.Style.FILL
                }
                canvas.drawPaint(paint)
                holder.unlockCanvasAndPost(canvas)

                handler.postDelayed({ drawCanvas(holder) }, 1000)
            }
        } catch (e: Exception) {
            e.printStackTrace()
        }

    }
}

WallpaperApplier.kt

import android.app.WallpaperManager
import android.content.ComponentName
import android.content.Context
import android.content.Intent

data class WallpaperListItem(val name: String, val resId: Int, val cls: Class<*>)

class WallpaperApplier(val ctx: Context) {
    fun apply(wallpaper: WallpaperListItem) {
        setWallpaperService(wallpaper.cls)
    }

    private fun setWallpaperService(wallpaperService: Class<*>) {
        val intent = Intent(WallpaperManager.ACTION_CHANGE_LIVE_WALLPAPER)
        intent.putExtra(
            WallpaperManager.EXTRA_LIVE_WALLPAPER_COMPONENT,
            ComponentName(ctx, wallpaperService)
        )
        intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK
        ctx.startActivity(intent)
    }
}