onTextChanged 由于两个超类覆盖而触发两次

Question

我制作了自定义视图并添加了 TextWatcher，但 onTextChanged 方法也在 TextView 上。当我覆盖它时，它适用于 2 个超类。 是否可以只覆盖一个超类？

class PhoneEditText(context: Context, attrs: AttributeSet?) : AppCompatEditText(context, attrs!!),
    TextWatcher {

    override fun beforeTextChanged(charSequence: CharSequence, i: Int, i1: Int, i2: Int) {}

    override fun onTextChanged(charSequence: CharSequence, start: Int, before: Int, count: Int) {
        Timber.d("onTextChanged count = $count")
    }

    override fun afterTextChanged(editable: Editable) {}

Answer 1

您继承了 AppCompatEditText 并实现了 TextWatcher 接口，这意味着当您在自定义类中重写 onTextChanged 等方法时，您正在扩展 AppCompatEditText 类和 TextWatcher 接口的行为，实际上您是在为超类/接口重写它们您正在扩展/实施。

class PhoneEditText(context: Context, attrs: AttributeSet?) : AppCompatEditText(context, attrs!!),
    TextWatcher {

    private var phoneTextWatcher: TextWatcher? = null

    init {
        phoneTextWatcher = object : TextWatcher {
            override fun beforeTextChanged(charSequence: CharSequence, i: Int, i1: Int, i2: Int) {}

            override fun onTextChanged(charSequence: CharSequence, start: Int, before: Int, count: Int) {
                Timber.d("PhoneEditText onTextChanged count = $count")
            }

            override fun afterTextChanged(editable: Editable) {}
        }

        addTextChangedListener(phoneTextWatcher)
    }

    // Rest of your class implementation...
}