VollyLibrary来解析JSON并将数据记录到Logconsole 我正在使用网址 :: http://www.androidbegin.com/tutorial/jsonparsetutorial.txt
JSON-响应::
{
"worldpopulation":
[
{
"rank":1,"country":"China",
"population":"1,354,040,000",
"flag":"http://www.androidbegin.com/tutorial/flag/china.png"
},
{
"rank":2,"country":"India",
"population":"1,210,193,422",
"flag":"http://www.androidbegin.com/tutorial/flag/india.png"
},
{
"rank":3,"country":"United States",
"population":"315,761,000",
"flag":"http://www.androidbegin.com/tutorial/flag/unitedstates.png"
},
{
"rank":4,"country":"Indonesia",
"population":"237,641,326",
"flag":"http://www.androidbegin.com/tutorial/flag/indonesia.png"
},
{
"rank":5,"country":"Brazil",
"population":"193,946,886",
"flag":"http://www.androidbegin.com/tutorial/flag/brazil.png"
},
{
"rank":6,"country":"Pakistan",
"population":"182,912,000",
"flag":"http://www.androidbegin.com/tutorial/flag/pakistan.png"
},
{
"rank":7,"country":"Nigeria",
"population":"170,901,000",
"flag":"http://www.androidbegin.com/tutorial/flag/nigeria.png"
},
{
"rank":8,"country":"Bangladesh",
"population":"152,518,015",
"flag":"http://www.androidbegin.com/tutorial/flag/bangladesh.png"
},
{
"rank":9,"country":"Russia",
"population":"143,369,806",
"flag":"http://www.androidbegin.com/tutorial/flag/russia.png"
},
{
"rank":10,"country":"Japan",
"population":"127,360,000",
"flag":"http://www.androidbegin.com/tutorial/flag/japan.png"
}
]
}
我面临的问题 ::
ex for below logs ::
- Log.d(" - - value - - ", value.toString());
- Log.d(" - - items - - ", items.toString());
- Log.d(" - - item - - ", item.toString());
- Log.d(" - - value.optString(rank) - - ",
value.optString("rank").toString());
MainActivity.java
public class MainActivity extends Activity {
//Declaring the variables
private String TAG = this.getClass().getSimpleName();
private ListView lstView;
private RequestQueue mRequestQueue;
private ArrayList<ModelClass> arrNews;
private LayoutInflater li;
private VollyAdapter va;
private ProgressDialog pd;
String url = "http://www.androidbegin.com/tutorial/jsonparsetutorial.txt";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_layout);
li=LayoutInflater.from(this);
arrNews=new ArrayList<ModelClass>();
va=new VollyAdapter();
lstView=(ListView) findViewById(R.id.listView);
lstView.setAdapter(va);
mRequestQueue = Volley.newRequestQueue(this);
pd = ProgressDialog.show(this,"Please Wait...","Please Wait...");
try{
Thread.sleep(2000);
}catch(Exception e){
}
JsonObjectRequest jr = new JsonObjectRequest(Request.Method.GET,url,null,new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
Log.i(TAG,response.toString());
parseJSON(response);
va.notifyDataSetChanged();
pd.dismiss();
; }
},new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.i(TAG,error.getMessage());
}
});
mRequestQueue.add(jr);
}
private void parseJSON(JSONObject response) {
try{
JSONObject value = response.getJSONObject("response");
Log.d(" - - value - - ", value.toString());
JSONArray items = value.getJSONArray("worldpopulation");
Log.d(" - - items - - ", items.toString());
for(int i=0;i<items.length();i++){
JSONObject item = items.getJSONObject(i);
Log.d(" - - item - - ", item.toString());
ModelClass nm = new ModelClass();
nm.setRank(value.optString("rank"));
Log.d(" - - value.optString(rank) - - ", value.optString("rank").toString());
nm.setCountry(value.optString("country"));
nm.setPopulation(value.optString("population"));
arrNews.add(nm);
}
}
catch(Exception e){
e.printStackTrace();
}
}
class VollyAdapter extends BaseAdapter{
@Override
public int getCount() {
return arrNews.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return arrNews.get(position);
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder vh;
if(convertView==null){
vh=new ViewHolder();
convertView=li.inflate(R.layout.row_listview, null);
vh.rank=(TextView) convertView.findViewById(R.id.txtRank);
vh.country=(TextView) convertView.findViewById(R.id.txtCountry);
vh.population=(TextView) convertView.findViewById(R.id.txtPopulation);
convertView.setTag(vh);
}else{
vh=(ViewHolder) convertView.getTag();
}
ModelClass mc=arrNews.get(position);
vh.rank.setText(mc.getRank());
vh.country.setText(mc.getCountry());
vh.population.setText(mc.getPopulation());
return convertView;
}
class ViewHolder{
TextView rank;
TextView country;
TextView population;
}
}
}
Logcat输出 ::
04-13 11:57:24.825: I/ActivityManager(79): Displayed com.example.vollytestdev/.MainActivity: +5s99ms
04-13 11:57:25.996: I/qtaguid(1251): Tagging socket 42 with tag 3ecd14a400000000(1053627556) for uid -1 failed errno=-2
04-13 11:57:25.996: I/NetworkManagementSocketTagger(1251): tagSocketFd(42, 1053627556, -1) failed with errno-2
04-13 11:57:27.915: D/Volley(1251): [109] BasicNetwork.logSlowRequests: HTTP response for request=<[ ] http://www.androidbegin.com/tutorial/jsonparsetutorial.txt 0x3ecd14a4 NORMAL 1> [lifetime=3108], [size=1497], [rc=200], [retryCount=0]
04-13 11:57:28.755: I/MainActivity(1251): {"worldpopulation":[{"rank":1,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/china.png","population":"1,354,040,000","country":"China"},{"rank":2,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/india.png","population":"1,210,193,422","country":"India"},{"rank":3,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/unitedstates.png","population":"315,761,000","country":"United States"},{"rank":4,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/indonesia.png","population":"237,641,326","country":"Indonesia"},{"rank":5,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/brazil.png","population":"193,946,886","country":"Brazil"},{"rank":6,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/pakistan.png","population":"182,912,000","country":"Pakistan"},{"rank":7,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/nigeria.png","population":"170,901,000","country":"Nigeria"},{"rank":8,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/bangladesh.png","population":"152,518,015","country":"Bangladesh"},{"rank":9,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/russia.png","population":"143,369,806","country":"Russia"},{"rank":10,"flag":"http:\/\/www.androidbegin.com\/tutorial\/flag\/japan.png","population":"127,360,000","country":"Japan"}]}
04-13 11:57:28.765: W/System.err(1251): org.json.JSONException: No value for response
04-13 11:57:28.775: W/System.err(1251): at org.json.JSONObject.get(JSONObject.java:354)
04-13 11:57:28.775: W/System.err(1251): at org.json.JSONObject.getJSONObject(JSONObject.java:569)
04-13 11:57:28.775: W/System.err(1251): at com.example.vollytestdev.MainActivity.parseJSON(MainActivity.java:79)
04-13 11:57:28.775: W/System.err(1251): at com.example.vollytestdev.MainActivity.access$3(MainActivity.java:77)
04-13 11:57:28.786: W/System.err(1251): at com.example.vollytestdev.MainActivity$1.onResponse(MainActivity.java:62)
04-13 11:57:28.786: W/System.err(1251): at com.example.vollytestdev.MainActivity$1.onResponse(MainActivity.java:1)
04-13 11:57:28.786: W/System.err(1251): at com.android.volley.toolbox.JsonRequest.deliverResponse(JsonRequest.java:65)
04-13 11:57:28.786: W/System.err(1251): at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:99)
04-13 11:57:28.795: W/System.err(1251): at android.os.Handler.handleCallback(Handler.java:605)
04-13 11:57:28.795: W/System.err(1251): at android.os.Handler.dispatchMessage(Handler.java:92)
04-13 11:57:28.805: W/System.err(1251): at android.os.Looper.loop(Looper.java:137)
04-13 11:57:28.815: W/System.err(1251): at android.app.ActivityThread.main(ActivityThread.java:4340)
04-13 11:57:28.825: W/System.err(1251): at java.lang.reflect.Method.invokeNative(Native Method)
04-13 11:57:28.825: W/System.err(1251): at java.lang.reflect.Method.invoke(Method.java:511)
04-13 11:57:28.825: W/System.err(1251): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
04-13 11:57:28.835: W/System.err(1251): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
04-13 11:57:28.845: W/System.err(1251): at dalvik.system.NativeStart.main(Native Method)
04-13 11:57:28.865: D/Volley(1251): [1] Request.finish: 4658 ms: [ ] http://www.androidbegin.com/tutorial/jsonparsetutorial.txt 0x3ecd14a4 NORMAL 1
04-13 11:59:45.394: D/dalvikvm(296): GC_CONCURRENT freed 383K, 6% free 10316K/10951K, paused 13ms+8ms
04-13 12:03:02.685: W/ThrottleService(79): unable to find stats for iface rmnet0
答案 0 :(得分：1)
试试这个..
像parseJSON(response.toString());
private void parseJSON(String response) {
try{
JSONObject value = new JSONObject(response);
Log.d(" - - value - - ", value.toString());
JSONArray items = value.getJSONArray("worldpopulation");
Log.d(" - - items - - ", items.toString());
for(int i=0;i<items.length();i++){
JSONObject item = items.getJSONObject(i);
Log.d(" - - item - - ", item.toString());
ModelClass nm = new ModelClass();
nm.setRank(item.optString("rank"));
Log.d(" - - item.optString(rank) - - ", item.optString("rank").toString());
nm.setCountry(item.optString("country"));
nm.setPopulation(item.optString("population"));
arrNews.add(nm);
}
}
catch(Exception e){
e.printStackTrace();
}
}