计算JSON数组中的元素数,并在Textview-Android上显示结果
我想计算通过JSON数组获得的元素数,并使用.settext()方法在TextView上显示它。 我得到了以下JSON数组: { "result": [ { "id":"283", "fullname":"shyam", "contactno":"898888888", "collegename":"mjc", "emailaddress":"shyamzawar", "eventname":"gaming" }, { "id":"285", "fullname":"ffca", "contactno":"8888888888", "collegename":"Brihan maharashtra College of Commerce (BMCC)", "emailaddress":"shyamzawar@ymail.com", "eventname":"FootBall" } ] } { “结果”: [ { “id”:“283”, “全名”:“shyam”, “联系人编号”:“89888888”, “collegename”:“mjc”, “电子邮件地址”:“shyamzawar”, “事件名称”:“游戏” }, { “id”:“285”, “全名”:“ffca”, “联系人编号”:“8888888888”, “学院名称”:“布里汉马哈拉施特拉商学院(BMCC)”, “电子邮件地址”:”shyamzawar@ymail.com", “事件名称”:“足球” } ] } 以下是我的活动:计算JSON数组中的元素数,并在Textview-Android上显示结果,android,arrays,json,parsing,Android,Arrays,Json,Parsing,我想计算通过JSON数组获得的元素数,并使用.settext()方法在TextView上显示它。 我得到了以下JSON数组: { "result": [ { "id":"283", "fullname":"shyam", "contactno":"898888888", "collegename":"mjc", "emailaddress":"shyamzawar",
private static final String TAG = "userList";
private List<FeedItem> feedsList;
private RecyclerView mRecyclerView;
private MyRecyclerAdapter adapter;
private ProgressBar progressBar;
private TextView ParticipantsCounts;
int count=0;
private SwipeRefreshLayout swipeRefreshLayout;
private final String url="http://bmcctroika.hol.es/get-data.php";;
private int offSet = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_admin);
// Initialize recycler view
mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
progressBar = (ProgressBar) findViewById(R.id.progress_bar);
progressBar.setVisibility(View.VISIBLE);
ParticipantsCounts= (TextView) findViewById(R.id.ParticipantsCount);
// Downloading data from below url
new AsyncHttpTask().execute(url);
swipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.swipe_refresh_layout);
swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
refreshitems();
}
});
}
private void refreshitems() {
new AsyncHttpTask().execute(url);
}
@Override
public void onRefresh() {
new AsyncHttpTask().execute(url);
}
public class AsyncHttpTask extends AsyncTask<String, Void, Integer> {
@Override
protected void onPreExecute() {
setProgressBarIndeterminateVisibility(true);
}
@Override
protected Integer doInBackground(String... params) {
Integer result = 0;
HttpURLConnection urlConnection;
try {
URL url = new URL(params[0]);
urlConnection = (HttpURLConnection) url.openConnection();
int statusCode = urlConnection.getResponseCode();
// 200 represents HTTP OK
if (statusCode == 200)
{
BufferedReader r = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
StringBuilder response = new StringBuilder();
String line;
while ((line = r.readLine()) != null)
{
response.append(line);
}
parseResult(response.toString());
result = 1; // Successful
} else {
result = 0; //"Failed to fetch data!";
}
} catch (Exception e) {
Log.d(TAG, e.getLocalizedMessage());
}
return result; //"Failed to fetch data!";
}
@Override
protected void onPostExecute(Integer result)
{
// Download complete.
progressBar.setVisibility(View.GONE);
if (result == 1)
{
adapter = new MyRecyclerAdapter(AdminActivity.this, feedsList);
mRecyclerView.setAdapter(adapter);
} else
{
Toast.makeText(AdminActivity.this, "Failed to fetch data!", Toast.LENGTH_SHORT).show();
}
swipeRefreshLayout.setRefreshing(false);
}
}
private void parseResult(String result) {
try {
JSONObject response = new JSONObject(result);
JSONArray posts = response.optJSONArray("result");
feedsList = new ArrayList<>();
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.optJSONObject(i);
FeedItem item = new FeedItem();
item.setTitle(post.optString("fullname"));
item.setContact(post.optString("contactno"));
item.setEmail(post.optString("emailaddress"));
item.setEventname(post.optString("eventname"));
item.setCollegename(post.optString("collegename"));
feedsList.add(item);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
private static final String TAG=“userList”;
私有列表feedsList;
私人回收视图mRecyclerView;
私人MyRecyclerAdapter适配器;
私人ProgressBar ProgressBar;
私人文本视图参与者;
整数计数=0;
私人SwipeRefreshLayout SwipeRefreshLayout;
私有最终字符串url=”http://bmcctroika.hol.es/get-data.php";;
私有整数偏移=0;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_admin);
//初始化回收器视图
mRecyclerView=(RecyclerView)findViewById(R.id.recycler\u视图);
mRecyclerView.setLayoutManager(新的LinearLayoutManager(this));
progressBar=(progressBar)findViewById(R.id.progress\u bar);
progressBar.setVisibility(View.VISIBLE);
ParticipantSconts=(TextView)findViewById(R.id.ParticipantScont);
//从下面的url下载数据
新建AsyncHttpTask().execute(url);
swipeRefreshLayout=(swipeRefreshLayout)findViewById(R.id.swipe\u refresh\u layout);
swipeRefreshLayout.setOnRefreshListener(新的swipeRefreshLayout.OnRefreshListener()){
@凌驾
公共void onRefresh(){
刷新项目();
}
});
}
私有项目(){
新建AsyncHttpTask().execute(url);
}
@凌驾
公共void onRefresh(){
新建AsyncHttpTask().execute(url);
}
公共类AsyncHttpTask扩展了AsyncTask{
@凌驾
受保护的void onPreExecute(){
SetProgressBarInDeterminateVibility(真);
}
@凌驾
受保护的整数doInBackground(字符串…参数){
整数结果=0;
HttpURLConnection-urlConnection;
试一试{
URL=新URL(参数[0]);
urlConnection=(HttpURLConnection)url.openConnection();
int statusCode=urlConnection.getResponseCode();
//200表示HTTP OK
如果(状态代码==200)
{
BufferedReader r=新的BufferedReader(新的InputStreamReader(urlConnection.getInputStream());
StringBuilder响应=新建StringBuilder();
弦线;
而((line=r.readLine())!=null)
{
响应。追加(行);
}
parseResult(response.toString());
结果=1;//成功
}否则{
结果=0;//“无法获取数据!”;
}
}捕获(例外e){
Log.d(标记,例如getLocalizedMessage());
}
返回结果;//“无法获取数据!”;
}
@凌驾
受保护的void onPostExecute(整数结果)
{
//下载完整。
progressBar.setVisibility(View.GONE);
如果(结果==1)
{
适配器=新的MyRecyclerAdapter(AdminActivity.this,feedsList);
mRecyclerView.setAdapter(适配器);
}否则
{
Toast.makeText(adminivity.this,“未能获取数据!”,Toast.LENGTH_SHORT.show();
}
swipeRefreshLayout.setRefreshing(false);
}
}
私有void parseResult(字符串结果){
试一试{
JSONObject响应=新JSONObject(结果);
JSONArray posts=response.optJSONArray(“结果”);
feedsList=新的ArrayList();
对于(int i=0;i
您需要获得结果的长度
JSONArray
。因此,在代码中,您可以获得posts
--JSONArray posts=response.optJSONArray(“结果”)代码>。
这将为您提供结果数组中的项数:
private void parseResult(String result) {
try {
JSONObject response = new JSONObject(result);
JSONArray posts = response.optJSONArray("result");
int number = posts.length();
//then to set it to the text view:
ParticipantsCounts.setText(String.valueOf(number));
//the rest of your code ...
feedsList = new ArrayList<>();
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.optJSONObject(i);
FeedItem item = new FeedItem();
item.setTitle(post.optString("fullname"));
item.setContact(post.optString("contactno"));
item.setEmail(post.optString("emailaddress"));
item.setEventname(post.optString("eventname"));
item.setCollegename(post.optString("collegename"));
feedsList.add(item);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
private void parseResult(字符串结果){
试一试{
JSONObject响应=新JSONObject(结果);
JSONArray posts=response.optJSONArray(“结果”);
int number=posts.length();
//然后将其设置为文本视图:
ParticipantsCounts.setText(String.valueOf(number));
//剩下的代码。。。
feedsList=新的ArrayList();
对于(int i=0;i
太好了,我很高兴这有帮助。继续编码。嘿,等等,它在解析JSON数据时出错,计数工作正常,但现在,它