有关如何基于给定给“编辑文本”视图的计数值动态实现线性布局的代码

Question

我正在研究个人详细信息模型，有2个单选选项已婚和未婚。点击已婚单选按钮，它将启用编辑文本，它将采取该已婚人士的子女号码。基于为编辑文本输入的值。正在实施动态线性布局。但是问题是当点击编辑文本时，它正在创建线性布局（在删除编辑文本时，线性布局也应该删除）。

我的代码是这样的。主要活动

et_childCount.addTextChangedListener(new TextWatcher() {
   @Override
       public void beforeTextChanged(CharSequence s, int start, int count, int after) {
   @Override
       public void onTextChanged(CharSequence s, int start, int before, int count) {
        }
    @Override
       public void afterTextChanged(Editable s) {
           if (s != null) {
               countI = childCount;
               noOfChild = countI;
                if (noOfChild >= 1) {
                   for (int i = 1; i <= noOfChild; i++) {
                       LinearLayout linearLayout = new LinearLayout(getActivity());
                       LayoutParams params = new LinearLayout.LayoutParams(
                               LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
                       linearLayout.setLayoutParams(params);
                       linearLayout.setOrientation(LinearLayout.VERTICAL);
                       TextView tv_BorderChildDetails = new TextView(getActivity());
                       tv_BorderChildDetails.setText("Child " + i);
                       tv_BorderChildDetails.setGravity(Gravity.CENTER_HORIZONTAL);
                       tv_BorderChildDetails.setBackgroundColor(getResources().getColor(R.color.colorPrimary));
                       linearLayout.addView(tv_BorderChildDetails);
                       EditText et_cName = new EditText(getActivity());
                       EditText et_cDob = new EditText(getActivity());
                       EditText et_cSchoolName = new EditText(getActivity());
                       et_cName.setHint("Child name");
                       et_cDob.setHint("Date of birth");
                       et_cSchoolName.setHint("School name");
                       childNameList.add(et_cName);
                       childDOBList.add(et_cDob);
                       childSchoolNameList.add(et_cSchoolName);
                       et_cName.setLayoutParams(params);
                       et_cDob.setLayoutParams(params);
                       et_cSchoolName.setLayoutParams(params);
                        linearLayout.addView(et_cName);
                       linearLayout.addView(et_cDob);
                       linearLayout.addView(et_cSchoolName); } } });

Answer 1

您可以使用EditText的属性addTextChangedListener。这是代码。

YourEditText.addTextChangedListener(new TextWatcher() {

    @Override
    public void afterTextChanged(Editable s) {
        int count = Integer.parseInt(YourEditText.getText().toString());
    }

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

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

});

将编辑文本输入类型更改为数字，否则如果有人输入文本，您将面临错误。

Listview listview= (ListView) findViewById(R.id.your_list_view);
Adapter adapter = new adapter (YourActivity.this, count);
listview.setAdapter(adapter );

只需在计数部分输入listview计数，这里是适配器类

 public class Adapter extends BaseAdapter {

    // Declare Variables \\
    Context mContext;
    LayoutInflater inflater;
    int count;

    public Adapter (Context context, String count) {
        mContext = context;
        inflater = LayoutInflater.from(mContext);
        this.count = Integer.parseInt(count);
        //---------------------------\\
    }

    public class ViewHolder {

    }

    @Override
    public int getCount() {
        return count; // Your Desired Count which you entered in EditText \\
    }

    @Override
    public Object getItem(int position) {
        return null; 
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    public View getView(final int position, View view, ViewGroup parent) {
        final ViewHolder holder;
        if (view == null) {
            holder = new ViewHolder();
            view = inflater.inflate(R.layout.lv_items, null);
            yourTv = view.findViewById(R.id.lv_item_tv);
            view.setTag(holder);
        } else {
            holder = (ViewHolder) view.getTag();
        }

        return view;
    }}

无论何时更改listview计数，都必须初始化适配器和listview。希望有帮助！

Answer 2

您可以像这样使用TextWatcher（）：

editText.addTextChangedListener(new TextWatcher() {
    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

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

    @Override
    public void afterTextChanged(Editable s) {
        // Convert the editable to int.
        int userInput = Integer.parseInt(s.getText().toString());
        // First we want to copy the data ArrayList so we don't affect the original one.
        ArrayList<Data> new = copyArray(originalDataArrayList);
        // Then we want to run a for loop to change the item count depending on the userInput value.
        for (int i = 0; i < newArray.size(); i++){
          if (i >= userInput){
            newArray.remove(i);
        }
      }
        // Now we have ArrayList with the required size.
        // Here you create a new adapter and pass the new ArrayList to it and set the ListView adapter as the new adapter.
    }
});

复制ArrayList方法：

    private ArrayList<Data> copyArray(ArrayList<Data> array) {
    ArrayList<Data> newArray = new ArrayList<>();
    newArray.addAll(array);
    return newArray;
}