Android 如何在演示课上显示Toast消息和对话框？

我为辅助监视器创建了演示类。我想在第二个监视器上显示一些对话框

对于toast，我发现：

但它不起作用

我唯一能想到的就是在我的基本布局上建立一个新的视图。 但是，它不能像对话框那样轻松地控制视图

这是我的托斯塔达。我将其更改为使用

Tostada.makeText（上下文、文本、时间）

object Tostada {
    private var mView: TextView? = null
    private var mWM: WindowManager? = null
    private val mParams = WindowManager.LayoutParams()
    private var mContext: Context? = null


    private val mHideRunnable = Runnable { handleHide() }

    /**
     * Assign the Tostada context. It can be a Presentation context. Remember to call setContext(null)
     * to clear the stored context when you no longer need this class, otherwise memory leaks can occur.
     *
     * @param context The context where the Tostada will be rendered
     */

    
    /**
     * Creates a Tostada with a gravity ana an offset x, y
     *
     * @param offsetX The X offset in pixels to apply to the gravity's location.
     * @param offsetY The Y offset in pixels to apply to the gravity's location.
     * @paran gravity The gravity constant
     */
    fun makeText(context: Context, text: String?, timeout: Int) {
        mContext = context
        mParams.packageName = context.packageName
        mView = TextView(context)
        mWM = context.getSystemService(Context.WINDOW_SERVICE) as WindowManager

        val params = mParams
        params.height = WindowManager.LayoutParams.WRAP_CONTENT
        params.width = WindowManager.LayoutParams.WRAP_CONTENT
        params.format = PixelFormat.TRANSLUCENT
        params.windowAnimations = 0
        params.type = WindowManager.LayoutParams.TYPE_TOAST
        params.title = "Toast"
        params.flags = (WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
                or WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
                or WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE)

        mParams.gravity = Gravity.BOTTOM or Gravity.CENTER_VERTICAL
        mParams.x = 0
        mParams.y = 50
        mParams.verticalMargin = 0f
        mParams.horizontalMargin = 0f

        checkNotNull(mContext) { "You must assign a context to this Tostada before it vcan be used" }

        // remove old timer for an ongoing tostada, if any
        mView!!.removeCallbacks(mHideRunnable)
        mView!!.text = text

        // Add the view to the window manager, if not already added
        if (mView!!.parent == null) mWM!!.addView(mView, mParams)

        // schedule for removal
        if (timeout > 0) mView!!.postDelayed(mHideRunnable, timeout.toLong())
    }

    private fun handleHide() {
        // remove the view if added
        if (mView!!.parent != null) mWM!!.removeView(mView)
    }
}