用齐射在片段中填充JSON listview [英] Populating JSON listview in a fragment with volley
本文介绍了用齐射在片段中填充JSON listview的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我是java/android编程中的绿色角色，但是我试图添加不同的教程来创建自定义应用程序，这将是一个很酷的实验，对于大多数人来说，这可能很容易，但是却陷入其中我正在尝试使用此导航抽屉视图分页器尝试使用此
I am a green horn in java/android programming but I was trying to add different tutorials to create a customized application that would be a cool experiment, this could be something very easy to most of the people here but am stuck in this one and I am trying to use this Navigation Drawer View Pager trying to populate the tab one fragment with this Custom ListView with Volley.from android hive "great tutorials btw".
我想将带有排球的自定义listview的 MainActivity.java 中的代码传输到导航抽屉中的 HomeFragment.java ，但出现错误.
I want to transfer the code in the MainActivity.java of custom listview with volley to a HomeFragment.java in navigation drawer but I get errors.
主要活动
public class MainActivity extends Activity {
// Log tag
private static final String TAG = MainActivity.class.getSimpleName();
// Movies json url
private static final String url = "http://api.androidhive.info/json/movies.json";
private ProgressDialog pDialog;
private List<Movie> movieList = new ArrayList<Movie>();
private ListView listView;
private CustomListAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.list);
adapter = new CustomListAdapter(this, movieList);
listView.setAdapter(adapter);
pDialog = new ProgressDialog(this);
// Showing progress dialog before making http request
pDialog.setMessage("Loading...");
pDialog.show();
// changing action bar color
getActionBar().setBackgroundDrawable(
new ColorDrawable(Color.parseColor("#1b1b1b")));
// Creating volley request obj
JsonArrayRequest movieReq = new JsonArrayRequest(url,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
Log.d(TAG, response.toString());
hidePDialog();
// Parsing json
for (int i = 0; i < response.length(); i++) {
try {
JSONObject obj = response.getJSONObject(i);
Movie movie = new Movie();
movie.setTitle(obj.getString("title"));
movie.setThumbnailUrl(obj.getString("image"));
movie.setRating(((Number) obj.get("rating"))
.doubleValue());
movie.setYear(obj.getInt("releaseYear"));
// Genre is json array
JSONArray genreArry = obj.getJSONArray("genre");
ArrayList<String> genre = new ArrayList<String> ();
for (int j = 0; j < genreArry.length(); j++) {
genre.add((String) genreArry.get(j));
}
movie.setGenre(genre);
// adding movie to movies array
movieList.add(movie);
} catch (JSONException e) {
e.printStackTrace();
}
}
// notifying list adapter about data changes
// so that it renders the list view with updated data
adapter.notifyDataSetChanged();
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
VolleyLog.d(TAG, "Error: " + error.getMessage());
hidePDialog();
}
});
// Adding request to request queue
AppController.getInstance().addToRequestQueue(movieReq);
}
@Override
public void onDestroy() {
super.onDestroy();
hidePDialog();
}
private void hidePDialog() {
if (pDialog != null) {
pDialog.dismiss();
pDialog = null;
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
HomeFragment
public class HomeFragment extends Fragment {
public HomeFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_home, container, false);
}
}
组合代码
public class HomeFragment extends Fragment{
private static final String TAG = HomeFragment.class.getSimpleName();
// Movies json url
private static final String url = "http://api.androidhive.info/json/movies.json";
private ProgressDialog pDialog;
private List<Movie> movieList = new ArrayList<Movie>();
private ListView listView;
private CustomListAdapter adapter;
//private TextView txtFragmentone;
@Override
public void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
}
public static HomeFragment newInstance() {
HomeFragment fragment = new HomeFragment();
return fragment;
}
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_home, container, false);
//txtFragmentone = (TextView) rootView.findViewById(R.id.txtFragmentOne);
//txtFragmentone.setText(R.string.fragment_tab_one);
rootView.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT ));
listView = (ListView) getActivity().findViewById(R.id.list);
adapter = new CustomListAdapter(this, movieList);
listView.setAdapter(adapter);
pDialog = new ProgressDialog(this);
// Showing progress dialog before making http request
pDialog.setMessage("Loading...");
pDialog.show();
// changing action bar color
getActivity().getActionBar().setBackgroundDrawable(
new ColorDrawable(Color.parseColor("#4cbaff")));
// Creating volley request obj
JsonArrayRequest movieReq = new JsonArrayRequest(url,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
Log.d(TAG, response.toString());
hidePDialog();
// Parsing json
for (int i = 0; i < response.length(); i++) {
try {
JSONObject obj = response.getJSONObject(i);
Movie movie = new Movie();
movie.setTitle(obj.getString("title"));
movie.setThumbnailUrl(obj.getString("image"));
movie.setRating(((Number) obj.get("rating"))
.doubleValue());
movie.setYear(obj.getInt("releaseYear"));
// Genre is json array
JSONArray genreArry = obj.getJSONArray("genre");
ArrayList<String> genre = new ArrayList<String>();
for (int j = 0; j < genreArry.length(); j++) {
genre.add((String) genreArry.get(j));
}
movie.setGenre(genre);
// adding movie to movies array
movieList.add(movie);
} catch (JSONException e) {
e.printStackTrace();
}
}
// notifying list adapter about data changes
// so that it renders the list view with updated data
adapter.notifyDataSetChanged();
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
VolleyLog.d(TAG, "Error: " + error.getMessage());
hidePDialog();
}
});
// Adding request to request queue
AppController.getInstance().addToRequestQueue(movieReq);
return rootView;
}
@Override
public void onDestroy() {
super.onDestroy();
hidePDialog();
}
private void hidePDialog() {
if (pDialog != null) {
pDialog.dismiss();
pDialog = null;
}
}
}
但是我出错了
rootView.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT ));
AppController.java
package androidhive.info.materialdesign.app;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.toolbox.ImageLoader;
import com.android.volley.toolbox.Volley;
import androidhive.info.materialdesign.util.LruBitmapCache;
import android.app.Application;
import android.text.TextUtils;
/**
* @author fanjavaid
*
*/
public class AppController extends Application {
public static final String TAG = AppController.class.getSimpleName();
private RequestQueue mRequestQueue;
private ImageLoader mImageLoader;
private static AppController mInstance;
@Override
public void onCreate() {
super.onCreate();
mInstance = this;
}
public static synchronized AppController getInstance() {
return mInstance;
}
public RequestQueue getRequestQueue() {
if (mRequestQueue == null) {
mRequestQueue = Volley.newRequestQueue(getApplicationContext());
}
return mRequestQueue;
}
public ImageLoader getImageLoader() {
getRequestQueue();
if (mImageLoader == null) {
mImageLoader = new ImageLoader(this.mRequestQueue,
new LruBitmapCache());
}
return this.mImageLoader;
}
public <T> void addToRequestQueue(Request<T> req, String tag) {
// set the default tag if tag is empty
req.setTag(TextUtils.isEmpty(tag) ? TAG : tag);
getRequestQueue().add(req);
}
public <T> void addToRequestQueue(Request<T> req) {
req.setTag(TAG);
getRequestQueue().add(req);
}
public void cancelPendingRequests(Object tag) {
if (mRequestQueue != null) {
mRequestQueue.cancelAll(tag);
}
}
}
fragment_home.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="androidhive.info.materialdesign.activity.HomeFragment">
<ListView
android:id="@+id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:divider="@color/list_divider"
android:dividerHeight="1dp"
android:listSelector="@drawable/list_row_selector" />
</RelativeLayout>
但是，如果我将 LayoutParams 更改为 Linear.LayoutParams ，它将崩溃如果您能帮助的话，那就太棒了！！！
However if i change LayoutParams to Linear.LayoutParams it crashes
If you could help it would be awesome !!!
推荐答案
我也正在尝试实现相同的目标.我结合了登录名和导航抽屉.我还尝试在家庭片段中显示静态数据，并且该数据有效.出于调试目的，我将默认片段更改为第二个片段.因此，现在当我打开抽屉并单击主页"选项卡时，我再次返回登录屏幕.
I am also trying to achieve the same. I combined the login and the navigation drawer. I also tried to display in home fragment a static data and it worked . For debugging purpose i changed the default fragment to the 2nd fragment. So now when i open the drawer, and click on the home tab, I again go back to the login screen.
这篇关于用齐射在片段中填充JSON listview的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
查看全文
