在res文件內 新建XML->LayoutXML

gotoXML編輯代碼

基本元素

android:layout_width="match_parent"
//尺寸和父容器相適應
android:layout_height="wrap_content"
//與輸入內容相適應
android:orientation="vertical"
//設置控件排布 水平/垂直
android:gravity="center"
//對齊方式

在android程序內加入

viewBinding{
    enbale = true
}

MainActivity控件綁定

private lateinit var binding:LayoutBinding
//databinding 人工綁定

binding = LayoutBinding.inflate(layoutInflater)

setContentView(binding.root)
//一定要注釋掉原有的setView

解決“使用binding綁定按鈕不管用”：查看setContentView下是否綁定了其他界面

Layout.xml

        <EditText
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="4"
            android:id="@+id/etvTest"
            android:background="#ff0000"
            android:hint="請輸入應發金額"
            android:inputType="number">
        </EditText>

binding.etvTest.addTextChangedListener(object:TextWatcher{
    override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
    }

    override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {

    }

    override fun afterTextChanged(s: Editable?) {
        var text = binding.etvTest.text.toString()
        val num:Float = text.toFloat()
        var result = cul(num)
        binding.txt2Test.text = result.toString()
        binding.txt1Test.text = (num-result).toString()
    }
})