Question

我没有。对于复选框（20），我所做的是如果用户选择任何复选框，其名称存储在数组中（例如，代码中的abc数组）。存储相应json的字符串变量的名称与复选框的名称相同。例如，如果Checkbox＆＃34; a＆＃34;单击，字符串值＆＃34; a＆＃34;存储在数组中，并且有一个名为＆＃34的字符串变量; a＆＃34;存储相关的json值。我需要的是，如果我传递存储在数组中的字符串值作为InputStream is = new ByteArrayInputStream（abc.get（i）.getBytes（）），它应该用于解析json的inputStream。但它给出了NullPointerException，因为字符串值＆＃34; a＆＃34;不等于字符串变量a。我怎么解决这个问题？我在这里没有想法了。有没有其他方法可以实现我想要做的事情？

代码：所选复选框的字符串值存储在数组

中

String a = "[{\n"
        + "\t\t\t\"title\": \"title1\",\n"
        + "\t\t\t\"describ\": \"describ1\"\n"
        + "}]";

String b = "[{\n"
        + "\"title\": \"title2\",\n"
        + "\"describ\": \"describ2\"\n"
        + "}]";

String c = "[{\n"
        + "\t\t\t\"title\": \"title3\",\n"
        + "\t\t\t\"describ\": \"describ3\"\n"
        + "}]";
//and all jsons required are there

ArrayList<String> abc;
@Override
protected void beforeTestForApp(Form f) {
    f.setTitle("abc");
    abc = new ArrayList<>();
    //I have stored "a" & "b" in the abc array here for simplicity, but it is dynamic,
    //ie. if the user select checkbox c, c will be stored in abc array and so on
    abc.add("a");
    abc.add("b");
    Button bb = new Button("go");
    bb.addActionListener((e) -> {
        showForm("TestForAppResult", null);
    });
    f.add(bb);
}

json解析器的表单并显示值：

@Override
protected void beforeTestForAppResult(Form f) {
    f.setLayout(new BoxLayout(BoxLayout.Y_AXIS));

    InputStream is;
    for (int i = 0; i < abc.size(); i++) {
        Label heading = new Label(abc.get(i));
        f.add(heading);
        //this gives error since abc.get(i) gives string value, not string variable
        is = new ByteArrayInputStream(abc.get(i).getBytes());
        showDetails(is, f);
    }
    //if i do this instead of for loop jst above, i can get the result but since what value'll be stored in an array is not known,it is not possible
          //is = new ByteArrayInputStream(a.getBytes());
          //showDetails(is, f);
          //is = new ByteArrayInputStream(b.getBytes());
          //showDetails(is, f);
}

private void showDetails(InputStream is, Form f) {
    JSONParser p = new JSONParser();
    Hashtable<String, Object> test;
    try {
        test = p.parse(new InputStreamReader(is));
        Vector aVector = (Vector) test.get("root");
        for (int j = 0; j < aVector.size(); j++) {
            Hashtable hm = (Hashtable) aVector.get(j);
            String title = (String) hm.get("title");
            String describ = (String) hm.get("describ");

            Label z = new Label(title);
            Label zz = new Label(describ);
            f.add(z);
            f.add(zz);
        }
    } catch (IOException ex) {
    }
}

Answer 1

我没有具体地解决你的问题，但我仍然试着给你一些镜头，以便你可以尝试。

如果我理解正确你有20个对象包含潜在的价值？那么你有一个JSONArray，只需迭代它并抓住那个JSONObject。

现在只使用parseJSON而不是parse，因为它已被弃用...

这是我的代码的简短片段

Intent getContentIntent = new Intent(Intent.ACTION_GET_CONTENT);
getContentIntent.addCategory(Intent.CATEGORY_OPENABLE);
getContentIntent.setType("text/plain"); 
String [] mimeTypes={"application/vnd.oasis.opendocument.text","application/msword","application/vnd.openxmlformats-officedocument.wordprocessingml.document","application/vnd.openxmlformats-officedocument.wordprocessingml.template","application/vnd.ms-word.document.macroEnabled.12","application/vnd.ms-word.template.macroEnabled.12","text/plain"};
                                    getContentIntent.putExtra(Intent.EXTRA_MIME_TYPES, mimeTypes);
                                    Intent intent = Intent.createChooser(getContentIntent, "Import Document"); 
                                    activity.startActivityForResult(intent, com.test.app.Constants.REQUESTCODES.FILE_CHOOSER.getValue());

使用数组中的字符串值作为字符串变量来解析json - codenameone

1 个答案: