Question

我试图将数据从Web服务拉到链接的微调器，而没有数据同时拉到两个微调器。代码的这一部分给出了一个错误：

spinnerFleet.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
            FleetModel selectedItem = (FleetModel) adapterView.getSelectedItem(); /*I think there was an error in this part of the code */
            int vgID = displayIdData(selectedItem);
            String jsonString = "{\"params1\":\"" + session_id + "\"," +
                    "\"params2\":\"5\"," +
                    "\"params3\":\"0\"," +
                    "\"params4\":\"0\"," +
                    "\"params5\":\"0\"," +
                    "\"params6\":\""+vgID+"\"," +
                    "\"params7\":\"0\"," +
                    "\"params8\":\"" + user_id + "\"}";
            new LoadSpinnerGroupTask().execute(jsonString);
        }

Answer 1

显然，adapterView.getSelectedItem()返回GroupModel，而不是FleetModel。因此，如果FleetModel不扩展GroupModel，它将抛出强制转换错误。

适配器项中的数据类型是什么？将其更改为FleetModel，或只写GroupModel selectedItem = (GroupModel) adapterView.getSelectedItem();

像这样尝试：

spinnerFleet.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
            FleetModel selectedItem = stateAdapter.getItem(i); /*I think there was an error in this part of the code */
            int vgID = displayIdData(selectedItem);
            String jsonString = "{\"params1\":\"" + session_id + "\"," +
                    "\"params2\":\"5\"," +
                    "\"params3\":\"0\"," +
                    "\"params4\":\"0\"," +
                    "\"params5\":\"0\"," +
                    "\"params6\":\""+vgID+"\"," +
                    "\"params7\":\"0\"," +
                    "\"params8\":\"" + user_id + "\"}";
            new LoadSpinnerGroupTask().execute(jsonString);
        }

无法将GroupModel强制转换为另一个模型

1 个答案: