在 Kotlin TextWatcher 中无按钮地乘以 2 个数字

Question

我的目标是使用如下所示的 2 个 edittext 自动显示用户在下面的 textView 中输入的数字。我怎么能这样做？因为这是迷恋。如果您能详细解释一下，我将不胜感激。提前致谢。

 items3=pronumber.text.toString() // Edittext
    items4=proprice.text.toString()// Edittext


    pronumber.addTextChangedListener ( object:TextWatcher{
        override fun afterTextChanged(p0: Editable?) {

        }

        override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
            TODO("Not yet implemented")
        }

        override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
            totalprice.text= "Toplam Tutar : "+(items3.toInt()*items4.toInt()).toString() +" TL"  //TextView

        }


    } )

    proprice.addTextChangedListener ( object:TextWatcher{
        override fun afterTextChanged(p0: Editable?) {

        }

        override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
            TODO("Not yet implemented")
        }

        override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
            totalprice.text= "Toplam Tutar : "+(items3.toInt()*items4.toInt()).toString() +" TL"  //TextView

        }


    } )


    items5=totalprice.text.toString()

Answer 1

您应该像这样更改您的代码

        items3=pronumber.text.toString() // Edittext
        items4=proprice.text.toString()// Edittext


        pronumber.addTextChangedListener ( object:TextWatcher{
            override fun afterTextChanged(p0: Editable?) {

            }

            override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
            }

            override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
                val first = pronumber.text.toString()
                val second = proprice.text.toString()
                totalprice.text =  if (first.isBlank() || second.isBlank()){
                    "Toplam Tutar : 0 TL"
                } else {
                    "Toplam Tutar : ${first.toInt().times(second.toInt())} TL"
                }

            }


        } )

        proprice.addTextChangedListener ( object:TextWatcher{
            override fun afterTextChanged(p0: Editable?) {

            }

            override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
            }

            override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
                totalprice.text =  if (first.isBlank() || second.isBlank()){
                    "Toplam Tutar : 0 TL"
                } else {
                    "Toplam Tutar : ${first.toInt().times(second.toInt())} TL"
                }
            }


        } )


        items5=totalprice.text.toString()

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