簡介

許多app會有需要顯示條碼的時候，在打開條碼時，通常會螢幕變亮使條碼的感應能夠靈敏。以下是食用方法:

1.取得當前螢幕亮度

fun getScreenBrightness(context: Context): Int {
    var nowBrightnessValue = 0
    val resolver: ContentResolver = context.getContentResolver()
    try {
        
        //亮度值範圍為0~255
        nowBrightnessValue = Settings.System.getInt(
            resolver,
            Settings.System.SCREEN_BRIGHTNESS
        )
    } catch (e: Exception) {
        e.printStackTrace()
    }
    return nowBrightnessValue
}

2.設定你要的螢幕亮度

 fun setScreenBrightnessLight(activity:Activity){
    val lp = activity!!.window.attributes
    
    //screenBrightness的值範圍為0~1 單位為float 
    lp.screenBrightness = java.lang.Float.valueOf(0.8f)
    activity!!.window.attributes = lp
}

3.還原原本的螢幕亮度

 fun setScreenBrightnessOrigin(activity: Activity,context: Context){
    val lp = activity!!.window.attributes
    
    //記得將單位0~255(Int)轉換為0-1f
    lp.screenBrightness = java.lang.Float.valueOf(getScreenBrightness(context!!) * (1f / 255f))
    activity!!.window.attributes = lp
}

參考資料

Android開發如何調整螢幕亮度