Question

我正在编写一个简单的Android应用程序，它使用API来获取一些数据但是我收到以下错误：

$('#checkout').on('click', function() { // on clicking the [Checkout] button
    try {
        // (1) perform validity check on the selected rows
        RowData.validityCheck(); // will throw if error is detected

        // (2) perform validity check on the #pos_drop selection
        var pos_city =  $("#pos-drop").val();
        if (!pos_city) {
            throw new Error('Please select a POS-City from the dropdown list.');
        }
        // (3) perform any further validity checks here (and throw accordingly)

        // Execution will only reach this point if no validity error is encountered.
        var link = "mailto:me@example.com" + "?subject=" + encodeURIComponent("Order") + "&body=Location: " + pos_city + '%0D%0A' + RowData.toEmailString(); // check that delimiter.
        console.log(link);
        window.location.href = link;
    } 
    catch(e) {
        console.error(e);
        $('#userMessage').text(e.message); // element #userMessage - eg a <span> - needs to exist somewhere on the page
    }
});

以下是我的代码：

 System.err: org.json.JSONException: No value for genre_ids
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at org.json.JSONObject.get(JSONObject.java:389)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at org.json.JSONObject.getJSONArray(JSONObject.java:584)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at com.adeel.android.movieinfoapp.Networking.onPostExecute(Networking.java:72)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at com.adeel.android.movieinfoapp.Networking.onPostExecute(Networking.java:21)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at android.os.AsyncTask.finish(AsyncTask.java:632)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at android.os.AsyncTask.access$600(AsyncTask.java:177)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:645)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at android.os.Handler.dispatchMessage(Handler.java:102)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at android.os.Looper.loop(Looper.java:145)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at android.app.ActivityThread.main(ActivityThread.java:5832)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at java.lang.reflect.Method.invoke(Native Method)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at java.lang.reflect.Method.invoke(Method.java:372)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
 07-19 18:12:08.164 24204-24204/com.adeel.android.movieinfoapp W/System.err:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)

}

我尝试编写的应用使用此JSON。

Answer 1

您没有正确解析嵌套JsonArray ..

此genre_ids数组位于results数组

下

使用以下代码：

try {
    JSONObject jsonObject = new JSONObject(s);  //string pass to your onPostExecute()
    JSONArray result = jsonObject.getJSONArray("results");
    for(int j=0;i<result.length;j++) {
        JSONObject inner = result.getJSONObject(j);
        JSONArray jsonStrings = inner.getJSONArray("genre_ids");
        String strings[] = new String[jsonStrings.length()];
        for(int i=0;i<strings.length;i++) {
            strings[i] = jsonStrings.getString(i);
        }
    }
} catch (JSONException e) {
    e.printStackTrace();
}

Answer 2

添加到rafsanahmad007点，如果使用“opt”而不是“get”，则可以获得空值而不是异常

try {
    JSONObject jsonObject = new JSONObject(s);
    JSONArray resultArray = jsonObject.optJSONArray("results");

    if (resultArray == null) {
        Log.d("MM", "Json array is null");

        return;
    }
    for (int i = 0; i < resultArray.length(); i++) {
        JSONObject resultObj = resultArray.getJSONObject(i);

        if (resultObj == null) {
            continue;
        }

        JSONArray jsonStrings = jsonObject.optJSONArray("genre_ids");

        if (jsonStrings != null) {
            String strings[] = new String[jsonStrings.length()];

            for (int j = 0; j < strings.length; j++) {
                strings[j] = jsonStrings.optString(j);
            }
        }

    }


} catch (JSONException e) {
    e.printStackTrace();
}

JSON例外：没有价值

2 个答案: