我在Android应用程序上遇到问题，我使用JSON解析从mysql获取数据。
当我选择一个listview项目并将其传递给另一个活动时，它会取一个随机值而不是我选择的那个。
以下是listview活动中的代码。
public class Outlets extends ListActivity{
// Progress Dialog
private ProgressDialog pDialog;
// testing on Emulator:
private static final String READ_OUTLETS_URL = "http://10.0.2.2:8081/bfc_webservice/outlet_list.php";
// JSON IDS:
private static final String TAG_SUCCESS = "success";
private static final String TAG_OUTLET_NAME = "outlet_name";
private static final String TAG_SPARKLING_CLASSIFICATION = "sparkling_classification";
private static final String TAG_ID = "id";
private static final String TAG_POSTS= "posts";
private static final String TAG_SPARKLING_CHANNEL = "sparkling_channel";
// An array of all of our comments
private JSONArray mOutlets = null;
// manages all of our comments in a list.
private ArrayList<HashMap<String, String>> mOutletsList;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.outlets);
}
@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
// loading the comments via AsyncTask
new LoadComments().execute();
}
/*public void addComment(View v) {
Intent i = new Intent(ShowComments.this, PostComment.class);
startActivity(i);
}
*/
/**
* Retrieves recent post data from the server.
*/
public void updateJSONdata() {
// Instantiate the arraylist to contain all the JSON data.
// we are going to use a bunch of key-value pairs, referring
// to the json element name, and the content.
mOutletsList = new ArrayList<HashMap<String, String>>();
// Instantiating the json parser J parser
JSONParser jParser = new JSONParser();
// Feed the beast our comments url, and it spits us
// back a JSON object. Boo-yeah Jerome.
JSONObject json = jParser.getJSONFromUrl(READ_OUTLETS_URL);
//Catcing Exceptions
try {
//Checking the amount of data rows.
mOutlets = json.getJSONArray(TAG_POSTS);
// looping through the database
for (int i = 0; i < mOutlets.length(); i++) {
JSONObject c = mOutlets.getJSONObject(i);
// gets the content of each tag
String outletname = c.getString(TAG_OUTLET_NAME);
String spark_channel = c.getString(TAG_SPARKLING_CHANNEL);
String spark_class = c.getString(TAG_SPARKLING_CLASSIFICATION);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
map.put(TAG_OUTLET_NAME, outletname);
map.put(TAG_SPARKLING_CHANNEL, spark_channel);
map.put(TAG_SPARKLING_CLASSIFICATION, spark_class);
// adding HashList to ArrayList
mOutletsList.add(map);
// JSON data parsing completed by hash mappings
// list
}
} catch (JSONException e) {
e.printStackTrace();
}
}
/**
* Inserts the parsed data into the listview.
*/
private void updateList() {
// For a ListActivity we need to set the List Adapter, and in order to do
//that, we need to create a ListAdapter. This SimpleAdapter,
//will utilize our updated Hashmapped ArrayList,
//use our single_post xml template for each item in our list,
//and place the appropriate info from the list to the
//correct GUI id. Order is important here.
ListAdapter adapter = new SimpleAdapter(this, mOutletsList,
R.layout.single_outlet, new String[] { TAG_OUTLET_NAME, TAG_SPARKLING_CHANNEL,
TAG_SPARKLING_CLASSIFICATION }, new int[] { R.id.outlet_name, R.id.sparkling_channel,
R.id.sparkling_classification });
// I shouldn't have to comment on this one:
setListAdapter(adapter);
// Optional: when the user clicks a list item we
//could do something. However, we will choose
//to do nothing...
ListView lv = getListView();
lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
int itemPosition = position;
TextView outname = (TextView)findViewById(R.id.outlet_name);
TextView channel = (TextView)findViewById(R.id.sparkling_channel);
TextView clas = (TextView)findViewById(R.id.sparkling_classification);
String foutname = outname.getText().toString();
String fchannel = channel.getText().toString();
String fclass = clas.getText().toString();
Intent i = new Intent(Outlets.this, ScoreSheet.class);
i.putExtra("outlt", foutname);
i.putExtra("chnl", fchannel);
i.putExtra("cls", fclass);
startActivity(i);
}
});
}
public class LoadComments extends AsyncTask<Void, Void, Boolean> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(Outlets.this);
pDialog.setMessage("Loading Outlets...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected Boolean doInBackground(Void... arg0) {
updateJSONdata();
return null;
}
@Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
pDialog.dismiss();
updateList();
}
}
}
我的下一个活动的代码是这个。我想测试我是否使用TextViews获得正确的值。
public class ScoreSheet extends Activity{
TextView oname, sch, scls;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.score_sheet);
oname = (TextView)findViewById(R.id.txtoutname);
sch = (TextView)findViewById(R.id.txtspchannel);
scls = (TextView)findViewById(R.id.txtspclass);
Intent myIntent = getIntent();
String ot = myIntent.getStringExtra("outlt");
String ch = myIntent.getStringExtra("chnl");
String cls = myIntent.getStringExtra("cls");
oname.setText(ot);
sch.setText(ch);
scls.setText(cls);
}
}
你的帮助在我心中永远受到赞赏。即使是其他方法，我也欢迎他们做同样的工作。非常感谢你们。
答案 0 :(得分：0)
更改此
TextView outname = (TextView)findViewById(R.id.outlet_name);
TextView channel = (TextView)findViewById(R.id.sparkling_channel);
TextView clas = (TextView)findViewById(R.id.sparkling_classification);
到
TextView outname = (TextView)view.findViewById(R.id.outlet_name);
TextView channel = (TextView)view.findViewById(R.id.sparkling_channel);
TextView clas = (TextView)view.findViewById(R.id.sparkling_classification);
您需要使用view查找视图。您可以按照以下方式进行意见化，而不是
另一种方式
lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
HashMap<String,String> map= (HashMap<String, String>) parent.getItemAtPosition(position); // use postion. get the map
String foutname =map.get(TAG_OUTLET_NAME); // get the value using key
String fchannel = map.get(TAG_SPARKLING_CHANNEL);
String fclass = map.get(TAG_SPARKLING_CLASSIFICATION);
...// rest of the code
}
});
答案 1 :(得分：0)
使用以下：
lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
int itemPosition = position;
View view1=(View) lv.getItemAtPosition(itemPosition );
TextView outname = (TextView)view1.findViewById(R.id.outlet_name);
TextView channel = (TextView)view1.findViewById(R.id.sparkling_channel);
TextView clas = (TextView)view1.findViewById(R.id.sparkling_classification);
String foutname = outname.getText().toString();
String fchannel = channel.getText().toString();
String fclass = clas.getText().toString();
Intent i = new Intent(Outlets.this, ScoreSheet.class);
i.putExtra("outlt", foutname);
i.putExtra("chnl", fchannel);
i.putExtra("cls", fclass);
startActivity(i);
}
});