onWindowFocusChanged.kt

   override fun onWindowFocusChanged(hasFocus: Boolean) {
        super.onWindowFocusChanged(hasFocus)

        // what the heck! 這件事做在 onResume() 中是沒有用的。害我試了好久
        val clipBoardManager = getSystemService(CLIPBOARD_SERVICE) as ClipboardManager
        val copiedString = clipBoardManager.primaryClip?.getItemAt(0)?.text?.toString() ?: ""
        if (copiedString.isNotEmpty()) {
            handleSendText(copiedString)
        }
    }