Question

嗨，这是我正在看的代码：

https://github.com/findup/Android_Sample_TodoApp/blob/master/src/jp/co/example/testapp/MainActivity.java

在第127行附近，它选择使用数据库连接从数据库中获取内容。

我不想从数据库中获取数据，而是使用ArrayList来保存数据。谁能帮我弄清楚我需要做什么？谢谢！

Answer 1

不是基于您的代码的一对一示例，但这将填充数据库表中的列表而不使用简单的游标：

public class MyListAdapter extends ListActivity {

    List<ContactGroup> groups = new ArrayList<ContactGroup>();

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

        this.groups = getGrpList();
        ContactGroupAdapter cAdapter = new ContactGroupAdapter(this); 
        setListAdapter(cAdapter);
    }

    private List<ContactGroup> getGrpList(){
        List<ContactGroup> grps = new ArrayList<ContactGroup>();
        ContentResolver cr = getContentResolver();
        Cursor groupCur = cr.query(Groups.CONTENT_URI, new String [] {Groups._ID, Groups.NAME}, null, null, Groups.NAME + " ASC");
        if (groupCur.getCount() > 0) {
            while (groupCur.moveToNext()) {
                ContactGroup newGroup = new ContactGroup();
                newGroup.Name = groupCur.getString(groupCur.getColumnIndex(Groups.NAME));
                newGroup.Id = groupCur.getString(groupCur.getColumnIndex(Groups._ID));
                grps.add(newGroup);
            }
        }
        return grps;
    }

    public class ContactGroupAdapter extends BaseAdapter{

        public ContactGroupAdapter(Context c) {
            mContext = c;
        }

        public int getCount() {
            return groups.size();
        }

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

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

        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder;
            if(convertView == null){
                LayoutInflater vi = LayoutInflater.from(this.mContext);  
                convertView = vi.inflate(R.layout.two_line_list_item, null);
                holder = new ViewHolder();
                convertView.setTag(holder); 
            }
            else {
                //Get view holder back
                holder = (ViewHolder) convertView.getTag();
            }
            ContactGroup cg = groups.get(position);
            if (cg != null) {
                //Name
                holder.toptext = (TextView) convertView.findViewById(R.id.text1);
                holder.toptext.setText(cg.Name);
                //ID
                holder.bottomtext = (TextView) convertView.findViewById(R.id.text2);
                holder.bottomtext.setText(cg.Id);
            }
            return convertView;
        }
        private Context mContext;

    }

    public static class ViewHolder {
        TextView toptext;
        TextView bottomtext;
    }

    public class ContactGroup{
        public String Id;
        public String Name;
    }
}

然后是XML文件...

two_line_list_item.xml：

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

    <TextView android:id="@+id/text1" android:textStyle="bold"
        android:layout_width="fill_parent" android:layout_height="wrap_content" />

    <TextView android:id="@+id/text2" android:textStyle="bold"
        android:layout_width="fill_parent" android:layout_height="wrap_content" />

</LinearLayout>

和main.xml：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="fill_parent"
    android:layout_height="fill_parent" android:paddingLeft="8dp"
    android:paddingRight="8dp">

    <ListView android:id="@+id/android:list" android:layout_width="fill_parent"
        android:layout_height="fill_parent" />

    <TextView android:id="@id/android:empty" android:layout_width="fill_parent"
        android:layout_height="fill_parent" android:text="No Groups" />

</LinearLayout>

修改代码以使用ArrayList而不是SimpleCursor

1 个答案: