檢查 Kotlin 中的 EditText 文本

Question

我的活動有一個editText，我想在運行時檢查輸入的文本，如果文本等於“1”，那么 r 會改變.. 如何在 Kotlin 中制作這個？

fun EditText.afterTextChanged(afterTextChanged: (String) -> Unit) {
    this.addTextChangedListener(object : TextWatcher {
        override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
            textView9.visibility = View.GONE
            spin7.visibility = View.GONE
            spin8.visibility = View.GONE
            spin9.visibility = View.GONE
        }

        override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
            val Edit = editText.text.toString()
            if (Edit.equals("1")){
                textView9.visibility = View.GONE
                spin7.visibility = View.GONE
                spin8.visibility = View.GONE
                spin9.visibility = View.GONE
            }
            else {
                textView9.visibility = View.VISIBLE
                spin7.visibility = View.VISIBLE
                spin8.visibility = View.VISIBLE
                spin9.visibility = View.VISIBLE
            }
        }

        override fun afterTextChanged(editable: Editable?) {
        }
    })
}

Answer 1

嘗試這個：

yourEditText.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 text = p0.toString()
            if (text == "1") {
                //do something
            } else {
                //do something else
            }
         }
     })

您可以在此處可視化這些方法的工作原理（來源）：