我已经尝试了大约2周的时间来尝试将ArrayList加载到微调器。从下面代码中注释掉的尝试中可以看出，我没有太多运气。我在代码中留下了评论，告诉你我已经尝试了数百种方法来做到这一点。我可以将数据传递给微调器，但它没有正确显示。我试图获取密钥：来自hashmap的数据，将arraylist加载到spinner，从arraylist获取对象等等。我不是很擅长Java / Android但是VB很优秀。我一直在用Android努力奋斗。我希望在这个问题上得到一些帮助。先感谢您。再次感谢。
我尝试上传图片，但我的代表是1.所以，这是我得到的：
THIS IS THE RESPONSE:
{"category":"Accessories"}
{"category":"Battery Packs"}
{"category":"Hunting Lights"}
{"category":"Other"}
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.NameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.os.Bundle;
import android.provider.SyncStateContract.Constants;
import android.util.Log;
import android.view.Menu;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
public class Shop extends Activity {
//PHP to get catagories
public static String url_to_send = "http://xxx.xxx.xxx.xxx/load_catagories.php";
//TAG to send to PHP to retrieve catagories
private static final String TAG_CATAGORIES= "catagories";
private static final String TAG_CATAGORY= "catagory";
//Success tag
private static final String TAG_SUCCESS = "success";
//Dialog
ProgressDialog pDialog;
//JSON Parser
JSONParser jParser = new JSONParser();
JSONArray catagories = null;
Spinner MySpinner;
ArrayList<HashMap<String, String>> catagoryList;
List<String> items;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_shop);
MySpinner = (Spinner)findViewById(R.id.spinner1);
// Hashmap for ListView
catagoryList = new ArrayList<HashMap<String, String>>();
new LoadAllProducts().execute();
}
String theCatagory;
class LoadAllProducts extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(Shop.this);
pDialog.setMessage("Loading Catagories. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
/**
* getting All products from url
* */
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url_to_send, "GET", params);
// Check your log cat for JSON reponse
Log.d("All Catagories: ", json.toString());
try {
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// products found
// Getting Array of Products
catagories = json.getJSONArray(TAG_CATAGORIES);
// looping through All Products
items = new ArrayList<String>();
for (int i = 0; i < catagories.length(); i++) {
JSONObject c = catagories.getJSONObject(i);
items.add(catagories.getString(i));
// Storing each json item in variable
theCatagory = c.getString(TAG_CATAGORY);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_CATAGORY, theCatagory);
// adding HashList to ArrayList
catagoryList.add(map);
}
} else {
// no products found
// Launch Add New product Activity
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog after getting all products
pDialog.dismiss();
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
/**
* Updating parsed JSON data into ListView
* */
// ListAdapter adapter = new SimpleAdapter(MainActivity.this, productsList,R.layout.list_item, new String[] { TAG_PID,TAG_NAME},new int[] { R.id.pid, R.id.name });
//setListAdapter(adapter);
//ListAdapter adapter=new LazyAdapter(Shop.this, catagoryList);
//list.setAdapter(adapter);
//setListAdapter(adapter);
//String[] myData = {};
// myData = catagoryList.toArray(new String[catagoryList.size()]);
// SimpleAdapter adapter = new SimpleAdapter(Shop.this, catagoryList,R.layout.list_item, new String[] { TAG_CATAGORY},new int[] { theCatagory });
// MySpinner.setAdapter(adapter);
//ArrayAdapter<String> adapter = new ArrayAdapter<String> (Shop.this, android.R.layout.simple_spinner_item, catagoryList);
// MySpinner.setAdapter(adapter);
//ArrayList<String> list=new ArrayList<String>();
//for(int i=0;i<catagories.length();i++)
//{
//try {
//list.add(catagories.getString(i));
//} catch (JSONException e) {
// TODO Auto-generated catch block
// e.printStackTrace();
//}
// }
String [] anArrayOfStrings = new String[theCatagory.length()];
items.toArray(anArrayOfStrings);
ArrayAdapter<String>spinnerMenu = new ArrayAdapter<String(Shop.this,android.R.layout.simple_list_item_1,anArrayOfStrings);
MySpinner.setAdapter(spinnerMenu);
}
});
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.shop, menu);
return true;
}
}
以下是所有Catagories：LogCat
06-13 10:50:59.120: D/All Catagories:(5329): {"success":1,"catagories":[{"catagory":"Accessories"},{"catagory":"Battery Packs"},{"catagory":"Hunting Lights"}]}
答案 0 :(得分：1)
您的代码相当混乱 - 可能是在您为使事情正常工作而进行的所有不同尝试之后 - 但我认为主要问题区域位于doInBackground()和onPostExecute()。
花了一分钟来清理你的代码后，一切都变得很好，这意味着你几乎就在那里。我主要简化了JSON解析逻辑;即你不需要Map，你应该做的只是将每个类别添加到一个列表中，该列表稍后将被输入到微调器适配器中。请参阅下面的代码片段 - 如果您发现以前的任何变量现在都丢失了，这可能意味着我删除了它们，因为它们不再需要了。
List<String> items = new ArrayList<String>();
/**
* getting All products from url
* */
protected String doInBackground(String... args) {
try {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url_to_send, "GET", params);
// Check your log cat for JSON reponse
Log.d("All Catagories: ", json.toString());
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// products found
// Getting Array of Products
JSONArray catagories = json.getJSONArray(TAG_CATAGORIES);
// looping through All Products
for (int i = 0; i < catagories.length(); i++) {
JSONObject c = catagories.getJSONObject(i);
// Storing each json item in variable
String category = c.getString(TAG_CATAGORY);
items.add(category);
}
} else {
// no products found
// Launch Add New product Activity
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
然后onPostExecute()，我从中删除了所有注释行。此外，此方法已在UI线程上运行，因此无需在Runnable上发布Handler。可以直接在这里触摸视图。唯一的另一个变化是将items（我们填充了doInBackground()中的类别）提供给适配器。
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog after getting all products
pDialog.dismiss();
ArrayAdapter<String> spinnerMenu = new ArrayAdapter<String>(Shop.this, android.R.layout.simple_list_item_1, items);
MySpinner.setAdapter(spinnerMenu);
}