我尝试从json数据中解析一些url，只从json中的url获取图像并将其显示为图片。但是我不断地从它那里得到错误，而且我不知道如何解决它（是的，我仍然是一个菜鸟）。
我使用here中的代码并稍微更改了json文件和代码。
这是代码
public class MainActivity extends Activity {
// Log tag
private static final String TAG = MainActivity.class.getSimpleName();
// Movies json url
static final String url = "http://url";
ProgressDialog pDialog;
List<Movie> movieList = new ArrayList<Movie>();
ListView listView;
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 {
Movie movie = new Movie();
JSONObject obj = response.getJSONObject(i);
movie.setTitle(obj.getString("title"));
//here where I try to parse the string from json file
String url2= obj.getString("image");
Document document = Jsoup.connect(url2).get();
Elements img = document.select("div [class=ipsBox] img[src]");
String imgSrc = img.attr("src");
movie.setThumbnailUrl(imgSrc);
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) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
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;
}}
这是我使用的json
[{
"title": "Dawn of the Planet of the Apes",
"image": "http://bato.to/comic/_/comics/000000-ultra-black-r1425",
"rating": 8.3,
"releaseYear": 2014,
"genre": ["Action", "Drama", "Sci-Fi"]
},
{
"title": "District 9",
"image": "http://bato.to/comic/_/comics/g-edition-r886",
"rating": 8,
"releaseYear": 2009,
"genre": ["Action", "Sci-Fi", "Thriller"]
},
{
"title": "Transformers: Age of Extinction",
"image": "http://otherurl",
"rating": 6.3,
"releaseYear": 2014,
"genre": ["Action", "Adventure", "Sci-Fi"]
},
{
"title": "X-Men: Days of Future Past",
"image": "http://otherurl",
"rating": 8.4,
"releaseYear": 2014,
"genre": ["Action", "Sci-Fi", "Thriller"]
},
{
"title": "How to Train Your Dragon",
"image": "http://otherurl",
"rating": 8.2,
"releaseYear": 2010,
"genre": ["Animation", "Adventure", "Family"]
}]
我运行程序后出现错误
我得到的错误
12-13 21:54:55.701: E/AndroidRuntime(28628): FATAL EXCEPTION: main
12-13 21:54:55.701: E/AndroidRuntime(28628): Process: info.androidhive.customlistviewvolley, PID: 28628
12-13 21:54:55.701: E/AndroidRuntime(28628): android.os.NetworkOnMainThreadException
12-13 21:54:55.701: E/AndroidRuntime(28628): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1145)
12-13 21:54:55.701: E/AndroidRuntime(28628): at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
12-13 21:54:55.701: E/AndroidRuntime(28628): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
12-13 21:54:55.701: E/AndroidRuntime(28628): at java.net.InetAddress.getAllByName(InetAddress.java:214)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.okhttp.internal.Dns$1.getAllByName(Dns.java:28)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.okhttp.internal.http.RouteSelector.resetNextInetSocketAddress(RouteSelector.java:216)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.okhttp.internal.http.RouteSelector.next(RouteSelector.java:122)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:292)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.okhttp.internal.http.HttpEngine.sendSocketRequest(HttpEngine.java:255)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:206)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.okhttp.internal.http.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:345)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.okhttp.internal.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:89)
12-13 21:54:55.701: E/AndroidRuntime(28628): at org.jsoup.helper.HttpConnection$Response.execute(HttpConnection.java:449)
12-13 21:54:55.701: E/AndroidRuntime(28628): at org.jsoup.helper.HttpConnection$Response.execute(HttpConnection.java:434)
12-13 21:54:55.701: E/AndroidRuntime(28628): at org.jsoup.helper.HttpConnection.execute(HttpConnection.java:181)
12-13 21:54:55.701: E/AndroidRuntime(28628): at org.jsoup.helper.HttpConnection.get(HttpConnection.java:170)
12-13 21:54:55.701: E/AndroidRuntime(28628): at info.androidhive.customlistviewvolley.MainActivity$1.onResponse(MainActivity.java:77)
12-13 21:54:55.701: E/AndroidRuntime(28628): at info.androidhive.customlistviewvolley.MainActivity$1.onResponse(MainActivity.java:1)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.volley.toolbox.JsonRequest.deliverResponse(JsonRequest.java:65)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:99)
12-13 21:54:55.701: E/AndroidRuntime(28628): at android.os.Handler.handleCallback(Handler.java:733)
12-13 21:54:55.701: E/AndroidRuntime(28628): at android.os.Handler.dispatchMessage(Handler.java:95)
12-13 21:54:55.701: E/AndroidRuntime(28628): at android.os.Looper.loop(Looper.java:136)
12-13 21:54:55.701: E/AndroidRuntime(28628): at android.app.ActivityThread.main(ActivityThread.java:5146)
12-13 21:54:55.701: E/AndroidRuntime(28628): at java.lang.reflect.Method.invokeNative(Native Method)
12-13 21:54:55.701: E/AndroidRuntime(28628): at java.lang.reflect.Method.invoke(Method.java:515)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:732)
12-13 21:54:55.701: E/AndroidRuntime(28628): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:566)
12-13 21:54:55.701: E/AndroidRuntime(28628): at dalvik.system.NativeStart.main(Native Method)
请帮帮我，非常感谢你的回答。
答案 0 :(得分：0)
根据this answer，我认为在开始解析之前需要这两行：
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);