我试图显示一个RecyclerView里面的Integers的ArrayList,ArrayList中的Integer值是从JSON下载的,所有完成的,我需要帮助的是显示它们在RecyclerView中。ArrayList不显示在RecyclerView
这是迄今为止我的代码,但RecyclerView不显示任何东西。
所有代码更新到我当前的代码
这里是在MainActivity的一部分:
public class MainActivity extends AppCompatActivity {
private ActivityMainViewModel viewmodel;
RecyclerView recyclerView;
MainAdapter mAdapter;
public static ArrayList<Integer> rideList = new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.activity_main);
ActivityMainBinding binding = DataBindingUtil.setContentView(this, R.layout.activity_main);
viewmodel = new ActivityMainViewModel();
binding.setViewmodel(viewmodel);
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
mAdapter = new MainAdapter(rideList);
recyclerView.setAdapter(mAdapter);
}
这里的MainAdapter类:
class MainAdapter extends android.support.v7.widget.RecyclerView.Adapter<MainAdapter.ViewHolder> {
private ArrayList<Integer> rideList;
public MainAdapter(ArrayList<Integer> rideList)
{
this.rideList = rideList;
}
@Override
public MainAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
{
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row, parent, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(MainAdapter.ViewHolder holder, int position)
{
holder.rideHeight.setText(String.valueOf(rideList.get(position)));
}
@Override
public int getItemCount()
{
return rideList.size();
}
public class ViewHolder extends RecyclerView.ViewHolder {
public TextView rideHeight;
public ViewHolder(View itemView) {
super(itemView);
rideHeight = (TextView) itemView.findViewById(R.id.rideHeight_textView);
}
}
}
row.xml :
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:id="@+id/rideHeight_textView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textSize="20sp"/>
</LinearLayout>
我知道,它可能看起来一团糟,但是那是因为我一直对如何使用RecyclerView,所以我可能从不同的教程混合,并试图自己出头搜索都对谷歌和YouTube。
谢谢!
编辑:加入要求JsonData代码:
JsonData:
public class JsonData
{
public ObservableField<String> dropHeight = new ObservableField<>();
public ObservableField<String> rideCount = new ObservableField<>();
int eID;
int sID;
public JsonData()
{
dropHeight.set("");
rideCount.set("");
}
public void downloadFromSkistar()
{
if (SettingsActivity.submitClicked)
{
eID = SettingsActivity.x;
sID = SettingsActivity.y;
}
else
{
eID = 3206;
sID = 11;
}
try
{
URL url = new URL("https://www.skistar.com/myskistar/api/v2/views/statisticspage.json?entityId=" + eID + "&seasonId=" + sID + " ");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(10000 /* milliseconds */);
conn.setConnectTimeout(15000 /* milliseconds */);
conn.setRequestMethod("GET");
// Starts the query
conn.connect();
int response = conn.getResponseCode();
Log.i("AndroidExample", "Response: " + response);
if (response == 200)
{
String json = getJson(conn.getInputStream());
JSONObject jsonObject = new JSONObject(json);
JSONArray jsonArray = jsonObject.getJSONArray("rideStatistics");
int reponame = 0;
int rHeight = 0;
for (int i = 0; i < jsonArray.length(); i++)
{
JSONObject skiRun = jsonArray.getJSONObject(i);
reponame += skiRun.getInt("height");
rHeight += skiRun.getInt("height");
MainActivity.rideList.add(new Integer(rHeight));
rHeight = 0;
}
final int height = reponame;
final int count = jsonArray.length();
new Handler(Looper.getMainLooper()).post(new Runnable() {
@Override
public void run() {
dropHeight.set("" + height);
rideCount.set("" + count);
}
});
}
}
catch (Exception e)
{
Log.i("AndroidExample", "Error");
}
finally
{
}
}
private String getJson(InputStream stream) throws IOException
{
BufferedReader reader;
reader = new BufferedReader(new InputStreamReader(stream, "UTF-8"));
StringBuilder builder = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
builder.append(line + '\n');
}
//Should be placed in finally
stream.close();
return builder.toString();
}
}
检查'JsonData.rideList'是否包含数据... –
代码看起来不错..首先检查您的JSON数据是否存在。调试你的代码。把断点放在你试图解析数据的地方......检查结果 –
JsonData.rideList在那一点似乎是空的,我如何让JsonData类先运行? – random1234