Question

我想显示数据库中的3个字段，但我不知道simple_list_item_1

SQLiteDatabase db = dbcenter.getReadableDatabase();
    cursor = db.rawQuery("SELECT * FROM TABLE", null);
    daftar = new String[cursor.getCount()];
    cursor.moveToFirst();
    for (int cc = 0; cc < cursor.getCount(); cc++) {
        cursor.moveToPosition(cc);
        daftar[cc] = cursor.getString(1).toString();
    }
    ListView01 = (ListView) view.findViewById(R.id.listView1);
    ListView01.setAdapter(new ArrayAdapter(getActivity(), android.R.layout.simple_list_item_1, daftar));
    ListView01.setSelected(true);

在上面的视图中，代码显示表中的数据，但只显示一个字段。

你能给我一个例子吗，用3代list_item用java代码将其替换为修改后的<TextView>

Answer 1

当您致电new ArrayAdapter(..., android.R.layout.simple_list_item_1, ...)时，您告诉系统使用android.R.layout.simple_list_item_1表示您的数据。如果这不起作用，那么实际上只有一个选择：自己处理充气和填充视图。您可以通过创建ArrayAdapter的自定义子类并覆盖onCreateView()来实现此目的。

官方文件：https://developer.android.com/reference/android/widget/ArrayAdapter.html

您还可以自定义集合中数据对象使用的视图类型。要自定义用于数据对象的视图类型，请覆盖getView(int, View, ViewGroup)并为视图资源充气。

Answer 2

创建一个名为custom_layout的xml，如

$parts= explode(",", $pattern);
$var1 = $parts[0];
$var2 = $parts[1];
$var3 = $parts[2];

使用像R.layout.custom_layout而不是android.R.layout.simple_list_item_1

Answer 3

您可以使用3个文本视图创建自定义列表视图

现在custom_list_view布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/name"
        android:text="@string/name"
        android:textSize="20sp"
        android:layout_marginTop="19dp"
        android:layout_alignParentTop="true"
        android:layout_toLeftOf="@+id/price"
        android:layout_toStartOf="@+id/price"
        android:layout_marginRight="30dp"
        android:layout_marginEnd="30dp"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/price"
        android:text="Price"
        android:textSize="20sp"
        android:layout_alignBaseline="@+id/name"
        android:layout_alignBottom="@+id/name"
        android:layout_centerHorizontal="true"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/stock"
        android:text="Stock"
        android:textSize="20sp"
        android:layout_alignBaseline="@+id/price"
        android:layout_alignBottom="@+id/price"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:layout_marginRight="81dp"
        android:layout_marginEnd="81dp"/>
    </RelativeLayout>

在布局中创建列表视图，我在mainactivity布局中创建

<?xml version="1.0" encoding="utf-8"?>
<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"
    tools:context="com.pro.salman.customlistview.MainActivity">

    <ListView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/list_item"/>

</RelativeLayout>

自定义列表视图类

public class CustomListView extends BaseAdapter {


    private ArrayList<HashMap<String,String>> list;
    private LayoutInflater mLayoutInflater;
    private Context mContext;

    public CustomListView(ArrayList<HashMap<String,String>> list,Context c) {
        this.list = list;
        this.mContext = c;
        mLayoutInflater = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

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

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

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

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {


        View view = mLayoutInflater.inflate(R.layout.custom_list_view,parent,false);
        Holder h = new Holder();

            // set id's
        h.name = (TextView)(view.findViewById(R.id.name));
        h.price = (TextView)(view.findViewById(R.id.price));
        h.stock = (TextView)(view.findViewById(R.id.stock));

        HashMap<String,String> hashMap = new HashMap<>();
        hashMap = list.get(position);

        h.name.setText(hashMap.get("nameKey"));
        h.price.setText(hashMap.get("priceKey"));
        h.stock.setText(hashMap.get("stockKey"));


        return view;
    }


    private class Holder
    {
        TextView name;
        TextView price;
        TextView stock;
    }
}

现在在主要活动课

public class MainActivity extends AppCompatActivity {

private ListView mListView;
private ArrayList<HashMap<String,String>> mArrayList;




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

    mArrayList = new ArrayList<HashMap<String, String>>();

    for(int i =0;i<20;i++)
    {
        HashMap<String,String> mHashMap = new HashMap<>();
        mHashMap.put("nameKey","name "+String.valueOf(i));
        mHashMap.put("priceKey","price "+String.valueOf(i));
        mHashMap.put("stockKey","stock "+String.valueOf(i));

        mArrayList.add(mHashMap);
    }


    mListView = (ListView)(findViewById(R.id.list_item));

    CustomListView customListView = new CustomListView(mArrayList,this);
    mListView.setAdapter(customListView);

}
}

结果

如何更改simple_list_item_1以修改list_item？

3 个答案: