<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
<uses-permission android:name="android.permission.SYSTEM_OVERLAY_WINDOW" />

class FloatWindowService : Service() {
 
    private val TAG = FloatWindowService::class.java.simpleName
    private var mFloatWindowManager: FloatWindowManager? = null
    private var mHomeKeyObserverReceiver: HomeKeyObserverReceiver? = null
 
    override fun onCreate() {
        TLogUtils.i(TAG, "onCreate: ")
        mFloatWindowManager = FloatWindowManager(applicationContext)
        mHomeKeyObserverReceiver = HomeKeyObserverReceiver()
 
        registerReceiver(mHomeKeyObserverReceiver, IntentFilter(Intent.ACTION_CLOSE_SYSTEM_DIALOGS))
        mFloatWindowManager!!.createWindow()
    }
 
    override fun onBind(intent: Intent?): IBinder? {
        return null
    }
 
    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        return START_NOT_STICKY
    }
 
    override fun onDestroy() {
        TLogUtils.i(TAG, "onDestroy: ")
        mFloatWindowManager?.removeWindow()
        if (mHomeKeyObserverReceiver != null) {
            unregisterReceiver(mHomeKeyObserverReceiver)
        }
    }
 
}

 
public void addView(View view, ViewGroup.LayoutParams params); // 添加 View 到 Window
public void updateViewLayout(View view, ViewGroup.LayoutParams params); //更新 View 在 Window 中的位置
public void removeView(View view); //刪除 View

class FloatWindowManager constructor(context: Context) {
 
    var isShowing = false
    private val TAG = FloatWindowManager::class.java.simpleName
    private var mContext: Context = context
    private var mFloatLayout = FloatLayout(mContext)
    private var mLayoutParams: WindowManager.LayoutParams? = null
    private var mWindowManager: WindowManager = context.getSystemService(Context.WINDOW_SERVICE) as WindowManager
 
    fun createWindow() {
        TLogUtils.i(TAG, "createWindow: start...")
        // 對象配置操作使用apply，額外的處理使用also
        mLayoutParams = WindowManager.LayoutParams().apply {
            type = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                // Android 8.0以后需要使用TYPE_APPLICATION_OVERLAY，不允許使用以下窗口類型來在其他應用和窗口上方顯示提醒窗口：TYPE_PHONE、TYPE_PRIORITY_PHONE、TYPE_SYSTEM_ALERT、TYPE_SYSTEM_OVERLAY、TYPE_SYSTEM_ERROR。
                WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY
            } else {
                // 在Android 8.0之前，懸浮窗口設置可以為TYPE_PHONE，這種類型是用于提供用戶交互操作的非應用窗口。
                // 在API Level  = 23的時候，需要在Android Manifest.xml文件中聲明權限SYSTEM_ALERT_WINDOW才能在其他應用上繪制控件
                WindowManager.LayoutParams.TYPE_PHONE
            }
            // 設置圖片格式，效果為背景透明
            format = PixelFormat.RGBA_8888
            // 設置浮動窗口不可聚焦（實現(xiàn)操作除浮動窗口外的其他可見窗口的操作）
            flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
            // 調整懸浮窗顯示的停靠位置為右側置頂
            gravity = Gravity.TOP or Gravity.END
            width = 800
            height = 200
            x = 20
            y = 40
        }
 
        mWindowManager.addView(mFloatLayout, mLayoutParams)
        TLogUtils.i(TAG, "createWindow: end...")
        isShowing = true
    }
 
    fun showWindow() {
        TLogUtils.i(TAG, "showWindow: isShowing = $isShowing")
        if (!isShowing) {
            if (mLayoutParams == null) {
                createWindow()
            } else {
                mWindowManager.addView(mFloatLayout, mLayoutParams)
                isShowing = true
            }
        }
    }
 
    fun removeWindow() {
        TLogUtils.i(TAG, "removeWindow: isShowing = $isShowing")
        mWindowManager.removeView(mFloatLayout)
        isShowing = false
    }
 
}

class FloatLayout @JvmOverloads constructor(context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0, defStyleRes: Int = 0) :
    ConstraintLayout(context, attrs, defStyleAttr, defStyleRes) {
 
    private var mTime: TCLTextView
    private var mDistance: TCLTextView
    private var mSpeed: TCLTextView
    private var mCalories: TCLTextView
 
    init {
        val view = LayoutInflater.from(context).inflate(R.layout.do_exercise_view_float_layout, this, true)
        mTime = view.findViewById(R.id.float_layout_tv_time)
        mDistance = view.findViewById(R.id.float_layout_tv_distance)
        mSpeed = view.findViewById(R.id.float_layout_tv_speed)
        mCalories = view.findViewById(R.id.float_layout_tv_calories)
    }
 
}

class HomeKeyObserverReceiver : BroadcastReceiver() {
 
    override fun onReceive(context: Context?, intent: Intent?) {
        try {
            val action = intent!!.action
            val reason = intent.getStringExtra("reason")
            TLogUtils.d(TAG, "HomeKeyObserverReceiver: action = $action,reason = $reason")
            if (Intent.ACTION_CLOSE_SYSTEM_DIALOGS == action && "homekey" == reason) {
                val keyCode = intent.getIntExtra("keycode", KeyEvent.KEYCODE_UNKNOWN)
                TLogUtils.d(TAG, "keyCode = $keyCode")
                context?.stopService(Intent(context, FloatWindowService::class.java))
            }
        } catch (ex: Exception) {
            ex.printStackTrace()
        }
    }
 
    companion object {
        private val TAG = HomeKeyObserverReceiver::class.java.simpleName
    }
 
}

object FloatWindowUtils {
 
    const val REQUEST_FLOAT_CODE = 1000
    private val TAG = FloatWindowUtils::class.java.simpleName
 
    /**
     * 判斷Service是否開啟
     */
    fun isServiceRunning(context: Context, ServiceName: String): Boolean {
        if (TextUtils.isEmpty(ServiceName)) {
            return false
        }
        val myManager = context.getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager
        val runningService = myManager.getRunningServices(1000) as ArrayList<ActivityManager.RunningServiceInfo>
        runningService.forEach {
            if (it.service.className == ServiceName) {
                return true
            }
        }
        return false
    }
 
    /**
     * 檢查懸浮窗權限是否開啟
     */
    @SuppressLint("NewApi")
    fun checkSuspendedWindowPermission(context: Activity, block: () -> Unit) {
        if (commonROMPermissionCheck(context)) {
            block()
        } else {
            Toast.makeText(context, "請開啟懸浮窗權限", Toast.LENGTH_SHORT).show()
            context.startActivityForResult(Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION).apply {
                data = Uri.parse("package:${context.packageName}")
            }, REQUEST_FLOAT_CODE)
        }
    }
 
    /**
     * 判斷懸浮窗權限權限
     */
    fun commonROMPermissionCheck(context: Context?): Boolean {
        var result = true
        if (Build.VERSION.SDK_INT >= 23) {
            try {
                val clazz: Class<*> = Settings::class.java
                val canDrawOverlays = clazz.getDeclaredMethod("canDrawOverlays", Context::class.java)
                result = canDrawOverlays.invoke(null, context) as Boolean
            } catch (e: Exception) {
                TLogUtils.e(TAG, e)
            }
        }
        return result
    }
 
}