1
你好我是新的android，所以請讓我知道我錯了。如何使用AsyncTask將json數組顯示到列表視圖？
我想將jsonarray轉換成自定義listview.I嘗試了很多，但我沒有得到解決方案。 我得到了我想要的strValue1的值（請檢查下面的代碼，Activites_Activity.java）。 現在，我想將這個strValue1傳遞給列表視圖。 但我無法將其轉換爲列表視圖。
請讓我知道我該怎麼辦？
我得到了錯誤
04-17 12:52:55.795: E/AndroidRuntime(765): FATAL EXCEPTION: AsyncTask #1
04-17 12:52:55.795: E/AndroidRuntime(765): java.lang.RuntimeException: An error occured while executing doInBackground()
04-17 12:52:55.795: E/AndroidRuntime(765): at android.os.AsyncTask$3.done(AsyncTask.java:200)
04-17 12:52:55.795: E/AndroidRuntime(765): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
04-17 12:52:55.795: E/AndroidRuntime(765): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
04-17 12:52:55.795: E/AndroidRuntime(765): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
04-17 12:52:55.795: E/AndroidRuntime(765): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
04-17 12:52:55.795: E/AndroidRuntime(765): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
04-17 12:52:55.795: E/AndroidRuntime(765): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
04-17 12:52:55.795: E/AndroidRuntime(765): at java.lang.Thread.run(Thread.java:1096)
04-17 12:52:55.795: E/AndroidRuntime(765): Caused by: android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
04-17 12:52:55.795: E/AndroidRuntime(765): at android.view.ViewRoot.checkThread(ViewRoot.java:2802)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.view.ViewRoot.focusableViewAvailable(ViewRoot.java:1596)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:451)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:451)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:451)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:451)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.view.View.setFlags(View.java:4474)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.view.View.setFocusableInTouchMode(View.java:3104)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.widget.AdapterView.checkFocus(AdapterView.java:694)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.widget.ListView.setAdapter(ListView.java:437)
04-17 12:52:55.795: E/AndroidRuntime(765): at com.rahul.cheerfoolz.activites.Activites_Activity$activites.doInBackground(Activites_Activity.java:141)
04-17 12:52:55.795: E/AndroidRuntime(765): at com.rahul.cheerfoolz.activites.Activites_Activity$activites.doInBackground(Activites_Activity.java:1)
04-17 12:52:55.795: E/AndroidRuntime(765): at android.os.AsyncTask$2.call(AsyncTask.java:185)
04-17 12:52:55.795: E/AndroidRuntime(765): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
04-17 12:52:55.795: E/AndroidRuntime(765): ... 4 more
感謝。
Activites_Activity.java
public class Activites_Activity extends CheerfoolznativeActivity {
TextView txtactivity;
ListView list;
LazyAdapter adapter;
ImageView img;
ProgressBar pgb;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_activites);
setHeader("Activites");
/*
list=(ListView)findViewById(R.id.activity_listView);
adapter=new LazyAdapter(this, mImages,mTitle);
list.setAdapter(adapter);
*/
txtactivity = (TextView) findViewById(R.id.activity_textView);
img=(ImageView)findViewById(R.id.activity_image);
pgb = (ProgressBar)findViewById(R.id.activity_progressBar);
new activites().execute();
}
public class activites extends AsyncTask<Void, Void, Void> {
String parsedString = "\n";
String strValue1 ;
public int i=0;
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
pgb.setVisibility(View.VISIBLE);
}
@Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
String url = " Here my json URL ";
String strResponse = util.makeWebCall(url);
try {
JSONObject objResponse = new JSONObject(strResponse);
JSONArray jsonnodes = objResponse.getJSONArray(API.cheerfoolz_activities.NODES);
Log.i(" NO of entries===>" +Activites_Activity.class.getName(),"Number of entries " + jsonnodes.length());
ArrayList<String> items = new ArrayList<String>();
for (i = 0; i < jsonnodes.length(); i++)
{
String str = Integer.toString(i);
Log.i("Value of i",str);
JSONObject jsonnode = jsonnodes.getJSONObject(i);
JSONObject jsonnodevalue = jsonnode.getJSONObject(API.cheerfoolz_activities.NODE);
strValue1 = jsonnodevalue.getString(API.cheerfoolz_activities.TITLE);
Log.i("JSONArray", strValue1);
//parsedString += " \n\n Value of stored parse : => " + strValue1;
parsedString = parsedString.trim(); //this will remove the blank white space
items.add(strValue1);
parsedString += " \n Value added in list => " + items;
Log.i("Value of items : ", parsedString);
}
//List<String> list = Arrays.asList((String[])jsonnodes.toString());
//String[] values= new String[]{items.toString()};
//myListView.setListAdapter(
/* list=(ListView)findViewById(R.id.activity_listView);
// adapter=new LazyAdapter((Activity) getApplicationContext(), mImages,mTitle);
list.setAdapter(adapter);*/
ListView myListView = (ListView)findViewById(R.id.activity_listView);
myListView.setAdapter(new ArrayAdapter(getApplicationContext(), android.R.layout.simple_expandable_list_item_1, items));
// ArrayAdapter<String> adapter= new ArrayAdapter<String>(Activites_Activity.this, android.R.layout.simple_list_item_1,items);
// myListView.setAdapter(adapter);
//Log.i("contact", items1);
}
catch (JSONException e) {
e.printStackTrace();
txtactivity.setText(e.getMessage());
}
return null;
}
@Override
protected void onProgressUpdate(Void... values) {
// TODO Auto-generated method stub
super.onProgressUpdate(values);
}
@Override
public void onPostExecute(Void result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
txtactivity.setText(parsedString);
pgb.setVisibility(View.GONE);
//img.setImageResource(parsedString);
}
}
}
LazyAdapter.java
public class LazyAdapter extends BaseAdapter{
private Activity context;
private String[] title;
private String[] images;
private LayoutInflater inflater;
public LazyAdapter(Activity context,String[] img ,String[] title) {
super();
this.context = context;
this.title = title;
this.images = img;
this.inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return title.length;
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return null;
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}
public static class ViewHolder
{
ImageView imgViewLogo;
TextView txtViewTitle;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ViewHolder holder;
if(convertView==null)
{
holder = new ViewHolder();
convertView = inflater.inflate(R.layout.activity_listitem, null);
holder.imgViewLogo = (ImageView) convertView.findViewById(R.id.activity_list_logo);
holder.txtViewTitle = (TextView) convertView.findViewById(R.id.activity_list_title);
convertView.setTag(holder);
}
else
holder=(ViewHolder)convertView.getTag();
// holder.imgViewLogo.setImageResource(images[position]);
holder.txtViewTitle.setText(title[position]);
return convertView;
}
}
makeWebCall.class
public static String makeWebCall(String url) {
DefaultHttpClient client = new DefaultHttpClient();
HttpGet httpRequest = new HttpGet(url);
try {
HttpResponse httpResponse = client.execute(httpRequest);
final int statusCode = httpResponse.getStatusLine().getStatusCode();
if (statusCode != HttpStatus.SC_OK) {
/* Log.i(getClass().getSimpleName(),
"Error => " + statusCode + " => for URL " + url);*/
return null;
}
HttpEntity entity = httpResponse.getEntity();
InputStream is = entity.getContent();
return iStream_to_String(is);
}
catch (IOException e) {
httpRequest.abort();
// Log.w(getClass().getSimpleName(), "Error for URL =>" + url, e);
}
return null;
}
public static String iStream_to_String(InputStream is1)
{
BufferedReader rd = new BufferedReader(new InputStreamReader(is1), 4096);
String line;
StringBuilder sb = new StringBuilder();
try {
while ((line = rd.readLine()) != null) {
sb.append(line);
}
rd.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String contentOfMyInputStream = sb.toString();
return contentOfMyInputStream;
}
謝謝，它的作品！ – 2012-04-17 08:06:30