android - 可使用 TextChangedListener 的引用进行编辑

Question

在 Xamarin 中，我可以为 EditText 对象的 TextChangedListener 编写一些代码吗？

这是我目前所拥有的:

public class InputTextWatcher
{
    public void afterTextChanged (Editable s)
    {

    }

    public void beforeTextChanged (CharSequence s, int start, int count, int after)
    {

    }

    public void onTextChanged (CharSequence s, int start, int before, int count)
    {

    }
}

这是我遇到的错误:

Error CS0246: The type or namespace name 'Editable' could not be found (are you missing a using directive or an assembly reference?)

Answer 1

您将需要实现 ITextWatcher:

using Android.Text;

public class InputTextWatcher : : Java.Lang.Object, ITextWatcher
{
    public void AfterTextChanged(IEditable s)
    {
        throw new NotImplementedException ();
    }

    public void BeforeTextChanged(Java.Lang.ICharSequence s, int start, int count, int after)
    {
        throw new NotImplementedException ();
    }

    public void OnTextChanged(Java.Lang.ICharSequence s, int start, int before, int count)
    {
        throw new NotImplementedException ();
    }
}

您还应该考虑改用事件处理程序:

        editText.BeforeTextChanged += HandleBeforeTextChanged;

        // or
        editText.TextChanged += (sender, e) => 
        {

        };
    }

    void HandleBeforeTextChanged (object sender, TextChangedEventArgs e)
    {

    }