使用数据库适配器从ListView中删除项目

Question

我有我的ListView和数据库适配器。如果用户点击listview中的某个地方，我想要一个对话框，如果用户点击“确定”按钮，我想删除用户点击的项目，这是怎么回事？

这是我的项目。我已经问了一些问题，非常感谢你们帮助我做这个项目非常感谢

这是我的listview .java文件

public class listview extends Activity {



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



        SQLiteDatabase db = openOrCreateDatabase("Orders.db", SQLiteDatabase.CREATE_IF_NECESSARY, null);
        Cursor crs = db.rawQuery("SELECT * FROM OrderedList", null);
        ListView listView = (ListView) findViewById(R.id.listView);
        String[] column1 = new String[crs.getCount()];
        double[] column2 = new double[crs.getCount()];
        int[] column3 = new int[crs.getCount()];
        double[] v2 = new double[crs.getCount()];
        int i = 0;
        Double sum = 0.0;
        int list_height = 0;
        while (crs.moveToNext()) {
            String item_name = crs.getString(crs.getColumnIndex("Food"));
            double item_price = crs.getDouble(crs.getColumnIndex("Price"));
            int temp_item_quantity = crs.getInt(crs.getColumnIndex("Quantity"));
            column1[i] = item_name;
            column2[i] = item_price;
            column3[i] = temp_item_quantity;
            v2[i] = column2[i];
            sum += v2[i];
            i++;
        }
        crs.close();
        ListView_Adapter adapter = new ListView_Adapter(this, column1, column2, column3);
        listView.setAdapter(adapter);

        TextView ttotal = (TextView)findViewById(R.id.ttotal);
        String initialtotal = String.valueOf(sum);
        ttotal.setText("P " + initialtotal);
    }

这是我的listview适配器

public class ListView_Adapter extends ArrayAdapter<String> {
    private final Context context;
    private String[] column1;
    private double[] column2;
    private int[] column3;

    public ListView_Adapter(Context context, String[] column1, double[] column2, int[] column3) {
        super(context, R.layout.list_adapter, column1);
        this.context = context;
        this.column1 = column1;
        this.column2 = column2;
        this.column3 = column3;

    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.list_adapter, parent, false);
        }
        TextView t1 = (TextView) convertView.findViewById(R.id.t1);
        TextView t2 = (TextView) convertView.findViewById(R.id.t2);
        TextView t3 = (TextView) convertView.findViewById(R.id.t3);

        t1.setText(column1[position]);
        t2.setText("₱" + column2[position]);
        t3.setText("" + column3[position]);
        return convertView;
    }
} 

这是我的databasehelper

public class MDB extends SQLiteOpenHelper {

    public MDB(Context context, String dbname, CursorFactory factory, int dbversion) {
        super(context, dbname, factory, dbversion);
    }
    SQLiteDatabase db;
    Cursor crs;
    @Override
    public void onCreate(SQLiteDatabase db) {

       db.execSQL("create table if not exists OrderedList(Food varchar, Price real, Quantity int);");
    }

    public void audittrail(){
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    }

}

Answer 1

您可以为ListView编写onItemClickListener。

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                @Override
                public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                    //call dialog
                    // you can set ok(positive) and cancel(negative) button
                    // for the ok button you can remove your listview item
                    //just do google

                }
            });