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我試圖找回GeoJSON數據在我的地震警報的應用程序自定義listview顯示，但應用程序意外關閉。這裏是我的代碼：代碼檢索GeoJSON的數據不能正常工作
CODE
public class JSONActivity extends ListActivity {
ListAdapter adapter;
String data;
private ProgressDialog pDialog;
ListView listview;
private static final String TAG_FEATURES= "features";
private static final String TAG_PROPERTIES= "properties";
private static final String TAG_MAG= "mag";
private static final String TAG_PLACE= "place";
private static final String TAG_TIME= "time";
private static final String TAG_TYPE= "type";
JSONArray features = null;
ArrayList<HashMap<String, String>> EarthquakeList;
public String readJSONFeed(String URL){
StringBuilder stringBuilder= new StringBuilder();
HttpClient client= new DefaultHttpClient();
HttpGet httpGet = new HttpGet(URL);
try{
HttpResponse response= client.execute(httpGet);
StatusLine statusLine= response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if(statusCode == 200){
HttpEntity entity= response.getEntity();
data= EntityUtils.toString(entity);
InputStream content = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(content));
String line;
while((line= reader.readLine())!= null)
{
stringBuilder.append(line);
}
}else{
Log.e("JSON", "Failed to download file");
}
}catch(ClientProtocolException e){
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
}
return stringBuilder.toString();
}
private class ReadJSONFeedTask extends AsyncTask<String, Void, String>{
// @Override
protected String doInBackground(String... urls) {
return readJSONFeed(urls[0]);
}
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(JSONActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
protected void onPostExecute(String result){
if (pDialog.isShowing())
pDialog.dismiss();
try{
JSONObject jsonObj = new JSONObject(data);
features = jsonObj.getJSONArray("features");
for (int i = 0; i < features.length(); i++)
{
JSONObject c = features.getJSONObject(i);
// Properties node is JSON Object
JSONObject properties = c.getJSONObject(TAG_PROPERTIES);
String mag = properties.getString(TAG_MAG);
String place = properties.getString(TAG_PLACE);
String type = properties.getString(TAG_TYPE);
String time = properties.getString(TAG_TIME);
Toast.makeText(getBaseContext(),mag,3000).show();
// tmp hash map for single contact
HashMap<String, String> earthquake = new HashMap<String, String>();
// adding each child node to HashMap key => value
earthquake.put(TAG_MAG, mag);
earthquake.put(TAG_PLACE, place);
earthquake.put(TAG_TYPE, type);
earthquake.put(TAG_TIME,time);
EarthquakeList.add(earthquake);
/**
* Updating parsed JSON data into ListView
* */
adapter = new SimpleAdapter(
JSONActivity.this , EarthquakeList ,
R.layout.list_item , new String[] { TAG_MAG, TAG_PLACE,
TAG_TIME,TAG_TYPE }, new int[] { R.id.mag,
R.id.place, R.id.time,R.id.type });
setListAdapter(adapter);
}
}catch(Exception e)
{
e.printStackTrace();
}
}
}
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
listview= (ListView)findViewById(R.id.listView1);
EarthquakeList = new ArrayList<HashMap<String, String>>();
listview.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Intent i = new Intent(getApplicationContext(), SingleListItem.class);
startActivity(i);
}});
new ReadJSONFeedTask().execute("http://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/4.5_day.geojson");
}
}
這是main.xml中
CODE
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />
<ListView
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
這是list_item.xml CODE
<TextView
android:id="@+id/mag"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingBottom="2dip"
android:paddingTop="6dip"
android:textColor="#43bd00"
android:textSize="16sp"
android:textStyle="bold"
/>
<TextView
android:id="@+id/place"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingBottom="2dip"
android:paddingTop="6dip"
android:textColor="#43bd00"
android:textSize="16sp"
android:textStyle="bold"
android:text="Place : " />
<TextView
android:id="@+id/time"
android:text="Time: "
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingBottom="2dip"
android:textColor="#acacac" />
<TextView
android:id="@+id/type"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="left"
android:text="Type: "
android:textColor="#5d5d5d"
android:textStyle="bold" />
logcat的
07-19 12:30:49.302: E/AndroidRuntime(279): FATAL EXCEPTION: main
07-19 12:30:49.302: E/AndroidRuntime(279): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.JSON/com.JSON.JSONActivity}: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android.R.id.list'
07-19 12:30:49.302: E/AndroidRuntime(279): at ``android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
07-19 12:30:49.302: E/AndroidRuntime(279): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
07-19 12:30:49.302: E/AndroidRuntime(279): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
07-19 12:30:49.302: E/AndroidRuntime(279): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
07-19 12:30:49.302: E/AndroidRuntime(279): at android.os.Handler.dispatchMessage(Handler.java:99)
07-19 12:30:49.302: E/AndroidRuntime(279): at android.os.Looper.loop(Looper.java:123)
07-19 12:30:49.302: E/AndroidRuntime(279): at android.app.ActivityThread.main(ActivityThread.java:4627)
07-19 12:30:49.302: E/AndroidRuntime(279): at java.lang.reflect.Method.invokeNative(Native Method)
07-19 12:30:49.302: E/AndroidRuntime(279): at java.lang.reflect.Method.invoke(Method.java:521)
07-19 12:30:49.302: E/AndroidRuntime(279): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
07-19 12:30:49.302: E/AndroidRuntime(279): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
07-19 12:30:49.302: E/AndroidRuntime(279): at dalvik.system.NativeStart.main(Native Method)
07-19 12:30:49.302: E/AndroidRuntime(279): Caused by: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android.R.id.list'
07-19 12:30:49.302: E/AndroidRuntime(279): at android.app.ListActivity.onContentChanged(ListActivity.java:245)
07-19 12:30:49.302: E/AndroidRuntime(279): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:201)
07-19 12:30:49.302: E/AndroidRuntime(279): at android.app.Activity.setContentView(Activity.java:1647)
07-19 12:30:49.302: E/AndroidRuntime(279): at com.JSON.JSONActivity.onCreate(JSONActivity.java:187)
07-19 12:30:49.302: E/AndroidRuntime(279): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
07-19 12:30:49.302: E/AndroidRuntime(279): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
07-19 12:30:49.302: E/AndroidRuntime(279): ... 11 more
解決在你的web服務器部分的GeoJSON的MIME類型？ – Wanderer
請加你堆棧跟蹤，並提供進一步的信息.. – lukaswelte