java - 使用 TextWatcher 在 EditText 中查找文本更改

Question

我正在尝试获取用户对 EditText 所做的修改，无论是插入还是删除。我使用 TextWatcher 但我没有得到正确的结果，而且有时“getChar(start, end) has end before start”错误。

editText = (EditText) findViewById(R.id.MyEditText);
editText.addTextChangedListener(new TextWatcher() {

    @override
    public void afterTextChanged(Editable s){}

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

        showToast("text removed: " + s.subSequence(start, count));
    }

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

        showToast("text added: " + s.subSequence(start, count));

    }



}

如您所见，我用于beforeTextChanged获取用户删除和onTextChanged插入的任何文本。请在这里阐明一下。谢谢！

API就在这里：http: //developer.android.com/reference/android/text/TextWatcher.html#afterTextChanged(android.text.Editable)

编辑：

我似乎想通了......这很愚蠢：s.subSequence(start, count))真的应该s.subSequence(start, start+count))

Answer 1

把你的函数放在里面afterTextChanged看看会发生什么

示例代码

seachbox.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            // TODO Auto-generated method stub

            fillData(SEARCH_ORDER ,s.toString());
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count,
                int after) {
            // TODO Auto-generated method stub

        }

        @Override
        public void afterTextChanged(Editable s) {
            // TODO Auto-generated method stub


    });

我希望它会工作

Answer 2

试试这个，我不确定你是想要剩下的单词（插入/更新后）还是字母（添加/删除）。

public class MainActivity extends Activity implements TextWatcher {

private EditText myEditText;
private String inputText;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    myEditText = (EditText) findViewById(R.id.testEditText);
    myEditText.addTextChangedListener(this);
}

@Override
public void afterTextChanged(Editable s) {      
    if (inputText.length() < s.toString().length()) {
        Toast.makeText(
                this,
                ("Text Added: " + s.toString().substring(inputText.length(),
                        s.toString().length())), Toast.LENGTH_SHORT).show();
    }
    else{
        Toast.makeText(
                this,
                ("Text Removed: " + inputText.substring(s.toString().length(),
                        inputText.length())), Toast.LENGTH_SHORT).show();
    }
}

@Override
public void beforeTextChanged(CharSequence s, int start, int count,
        int after) {
    inputText = s.toString();
}

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

}