Question

如果我输入的数字不在数据库中，那么我将从URL解析JSON值，所以我想吐司“未找到数据”

我尝试过

                    JSONArray jsonarray = new JSONArray(response);
if(jsonarray.length() == 0)
                    {

                        Toast.makeText(getApplicationContext(), "No Data Found", Toast.LENGTH_LONG).show();
                    }

但不吐槽我的应用程序，我不知道我的代码有什么问题

String url= "http://testes.com/get.php?id="+number;
    StringRequest stringRequest = new StringRequest(Request.Method.GET,
            url,
            new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    try {

                        JSONArray jsonarray = new JSONArray(response);
if(jsonarray.length() == 0)
                    {

                        Toast.makeText(getApplicationContext(), "No Data Found", Toast.LENGTH_LONG).show();
                    }

                        for(int i=0; i < jsonarray.length(); i++) {

                            JSONObject jsonobject = jsonarray.getJSONObject(i);

                                String id = jsonobject.getString("id");
                                String waktu = jsonobject.getString("waktu").trim();
                                String totalltr = jsonobject.getString("totalltr").trim();
                                String totalbulan = jsonobject.getString("totalbulan").trim();
                                String harga = jsonobject.getString("harga").trim();

                                str_id=id;
                                str_waktu=waktu;
                                str_totalltr=totalltr;
                                str_totalbulan=totalbulan;
                                str_harga=harga;

                                //textid.setText(" Id ="+id);
                                //textwaktu.setText(" Waktu ="+waktu);
                                //texttotalltr.setText(" Totalltr ="+totalltr);

                                Intent bukaActivity = new Intent(getApplicationContext(),MainActivity2.class);
                                bukaActivity.putExtra("id",str_id);
                                bukaActivity.putExtra("waktu",str_waktu);
                                bukaActivity.putExtra("totalltr",str_totalltr);
                                bukaActivity.putExtra("totalbulan",str_totalbulan);
                                bukaActivity.putExtra("harga",str_harga);
                                startActivity(bukaActivity);

                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }
            },
            new Response.ErrorListener() {

                @Override
                public void onErrorResponse(VolleyError error) {
                    if(error != null)
                    {

                        Toast.makeText(getApplicationContext(), "Something went wrong.", Toast.LENGTH_LONG).show();
                    }
                }
            }
    ); 
  MySingleton.getInstance(getApplicationContext()).addToRequestQueue(stringRequest);

如果输入的数字与数据库中的数字不一致，我希望显示烤面包

Answer 1

尝试使用：

Toast.makeText(this, "No data found", Toast.LENGTH_LONG).show();

如果这不起作用，请确保使用lambda在UI线程上运行吐司：

runOnUiThread(() -> {
       Toast.makeText(this, "No data found", Toast.LENGTH_LONG).show();
});

如何敬酒“找不到数据”请修复我的代码

1 个答案: