在 ListView 适配器中初始化空的 EditText

Question

我有 ListView 并且它包括 2 EditText我想在 activity started.How 时初始化 6 个空 EditText 我可以这样做吗？

我无法添加 list null 模型并进行设置，所以我不知道该如何处理。

This is listview_row.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">

<EditText
    android:id="@+id/SerialNumber"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_weight="3"
    android:ellipsize="end"
    android:padding="5dp"
    android:singleLine="true">
    <requestFocus />
</EditText>

<EditText
    android:id="@+id/countItem"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:ellipsize="end"
    android:padding="5dp"
    android:singleLine="true"
    android:inputType="number">
</EditText>

这是我的布局；

activity_reader.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">

<Button
    android:id="@+id/btn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content""
    android:text="btn" />

<GridLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ListView
        android:id="@+id/listview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:divider="@null" />
</GridLayout>

这是 ListView 适配器；

public class ListViewAdapter extends BaseAdapter {

public ArrayList<Model> productList;
Activity activity;
ViewHolder holder;
public ListViewAdapter(Activity activity, ArrayList<Census> productList) {
    super();
    this.activity = activity;
    this.productList = productList;
}

@Override
public int getCount() {
    return productList.size();
}

@Override
public Object getItem(int position) {
    return productList.get(position);
}

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

private class ViewHolder {
    EditText SerialNumber;
    EditText countItem;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    LayoutInflater inflater = activity.getLayoutInflater();

    if (convertView == null) {
        convertView = inflater.inflate(R.layout.listview_row, null);
        holder = new ViewHolder();
        holder.SerialNumber = (EditText) convertView.findViewById(R.id.SerialNumber );
        holder.countItem = (EditText) convertView.findViewById(R.id.countItem );;
        convertView.setTag(holder);
    } else {
        holder = (ViewHolder) convertView.getTag();
    }


    holder.SerialNumber.addTextChangedListener(new TextWatcher() { @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        holder.SerialNumber.requestFocus();

    }

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            holder.censusRowSerialNumber.requestFocus();
        }

        @Override
        public void afterTextChanged(Editable s) {
            //holder.countItem.requestFocus();
        }
    });

    Model item = productList.get(position);
    holder.SerialNumber.setText(item.getID().toString());
    holder.countItem.setText(String.valueOf(item.getQuantity()));
    return convertView;
}

}

Here is the Activity;

public class ReaderActivity extends AppCompatActivity {

EditText countItem,SerialNumber;
private ArrayList<Model> csList;
Model item;
ListViewAdapter adapter;
ListView lview;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_reader);

    csList = new ArrayList<Model>();
    lview = (ListView) findViewById(R.id.listview);
    adapter = new ListViewAdapter(this, csList);

    SerialNumber= findViewById(R.id.SerialNumber);
    countItem = findViewById(R.id.countItem );
    lview.setAdapter(adapter);
    adapter.notifyDataSetChanged();


}

Answer 1

为了实现 CRUD 操作，最好使用自定义布局。

例如LinearLayout，他的默认布局已经定义。现在根据运行时 requirement/parameters 你可以 add/edit/delete 所有这些。其逻辑可以完全属于您。这比创建静态视图和操作要方便。

让我向您展示自定义布局准备和添加到 rootiew 中。我给出了布局 landing_hori_view 具有 EditText 和 Button

的示例

public class LandingHorizontalView extends LinearLayout implements View.OnClickListener{


public LandingHorizontalView(Context context){
        super(context);
        initialize();
    }
public LandingHorizontalView(Context context, ModelClassObject modelObject,ButtonClicked listener){
        super(context);
        mTypeContent = modelObject;//If you want to pass some params for population
        mListener = listener;
        initialize();
    }
private void initialize(){
        View view = LayoutInflater.from(getContext()).inflate(R.layout.landing_hori_view, this, true);
        EditText edtOne =findViewById(R.id.txt_price_list);
        Button button= findViewById(R.id.btn_place_order);
        button.setTag(count);
        button.setOnClickListener(this);
    }

@Override
    public void onClick(View v) {
        if(v instanceof  Button){
            int count = (int) v.getTag();
            mListener.onButtonClicked(count);
        }

    }

public interface ButtonClicked{
        public void onButtonClicked(int index);
    }
}

在您的 parent activity 中，实现接口（此处 ButtonClicked）并处理点击 events/manipulating UI 等

@Override
    public void onButtonClicked(int index) {

}

现在，如何将这些添加到 parent 布局，创建一个 ScrollView 并包含一个 LinearLayout，LandinghorizontalView 将添加到其中。

下面是我的内容 parent Activity

<ScrollView
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:background="@android:color/white"
        app:layout_constraintTop_toBottomOf="@id/guideline"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"

        >
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical"
            android:id="@+id/landingScrollLinearView"
            >

        </LinearLayout>

现在要添加这个视图，可以进行以下操作。

    LandingHorizontalView horizontalView=new LandingHorizontalView(getActivity(),modelObject,this);
    mScrollLinearView.addView(horizontalView);

Now as per your comment, create few LandingHorizontalView and add to root. Now according to your logic/user interaction , keep on modifying mScrollLinearView

在 ListView 适配器中初始化空的 EditText

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