我正在开发一个Android应用程序，它将简单数据作为NAME发送到网络服务器，并可以从服务器中检索NAMES。使用php和mysql进行webservices。目前我完成了从web发送和接收数据到android。现在我想显示从我的网站数据库到我的android listview的名称。以下是我的代码
public class allProducts extends ListActivity {
// Progress Dialog
private ProgressDialog pDialog;
// Creating JSON Parser object
JSONParser jParser = new JSONParser();
ArrayList<HashMap<String, String>> productsList;
// url to get all products list
private static String url_all_products = "http://10.0.2.2/dinein/Model/getName.php";
// JSON Node names
private static final String TAG_NAME = "name";
//private static final String TAG_SUCCESS = "success";
//private static final String TAG_PRODUCTS = "products";
//private static final String TAG_PID = "pid";
// products JSONArray
JSONArray products = null;
static ArrayList<String> listItems=new ArrayList<String>();
//DEFINING STRING ADAPTER WHICH WILL HANDLE DATA OF LISTVIEW
ArrayAdapter<String> adapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.products);
// Hashmap for ListView
productsList = new ArrayList<HashMap<String, String>>();
// Loading products in Background Thread
new LoadAllProducts().execute();
// Get listview
ListView lv = getListView();
// on seleting single product
// launching Edit Product Screen
/* lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// getting values from selected ListItem
String pid = ((TextView) view.findViewById(R.id.pid)).getText()
.toString();
// Starting new intent
Intent in = new Intent(getApplicationContext(),
EditProductActivity.class);
// sending pid to next activity
in.putExtra(TAG_PID, pid);
// starting new activity and expecting some response back
startActivityForResult(in, 100);
}
});*/
}
// Response from Edit Product Activity
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// if result code 100
if (resultCode == 100) {
// if result code 100 is received
// means user edited/deleted product
// reload this screen again
Intent intent = getIntent();
finish();
startActivity(intent);
}
}
class LoadAllProducts extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(allProducts.this);
pDialog.setMessage("Loading products. 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_all_products, "POST", params);
// Check your log cat for JSON reponse
// Checking for SUCCESS TAG
int success = 1;
if (success == 1) {
Iterator<String> iter = json.keys();
Object value=null;
while (iter.hasNext()) {
String key = iter.next();
try {
value = json.get(key);
} catch (JSONException e) {
// Something went wrong!
}
}
}
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(
allProducts.this, productsList,
R.layout.name_list, new String[] {TAG_NAME},
new int[] { R.id.pid, R.id.name });
// updating listview
setListAdapter(adapter);
}
});
}
}
我想在列表视图的活动中显示我的数据。这是我的xml文件的样子
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<ListView
android:id="@+id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
和另一个
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="@+id/pid"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:visibility="gone" />
</RelativeLayout>
答案 0 :(得分：1)
如果您要扩展ListActivity，则ListView ID必须为android:id="@+id/android:list"。将您的xml更改为：
<ListView
android:id="@+id/android:list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
因为onPostExecute始终在Main UI Thread上执行，因此无需使用runOnUiThread从onPostExecute doInBackground方法更新用户界面，将onPostExecute方法代码更改为：
protected void onPostExecute(String file_url) {
// dismiss the dialog after getting all products
pDialog.dismiss();
ListAdapter adapter = new SimpleAdapter(
allProducts.this, productsList,
R.layout.name_list, new String[] {TAG_NAME},
new int[] { R.id.pid, R.id.name });
ListView listview = allProducts.this.getListView();
// updating listview
listview.setListAdapter(adapter);
}
答案 1 :(得分：0)
我发现你的代码有两个错误。
首先，您无法在列表中看到任何内容，因为行的textview可见性设置为GONE 。所以，改变它。
<TextView
android:id="@+id/pid"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
<!-- android:visibility="gone" -->
/>
其次，您的列表行只有一个字段（R.id.pid），您的代码尝试设置两个字段（R.id.pid，R.id。名）即可。很快，您有两个更改它，或添加另一个文本视图与android:id ="@+id/name"或删除您的适配器的R.id.name。
这是一个只使用你的pid字段的例子：
List<Map<String, String>> productsList = new ArrayList<Map<String,String>>();
HashMap<String, String> p1 = new HashMap<String, String>();
p1.put("key", "product1");
HashMap<String, String> p2 = new HashMap<String, String>();
p2.put("key", "product2");
HashMap<String, String> p3 = new HashMap<String, String>();
p3.put("key", "product3");
productsList.add(p1);
productsList.add(p2);
productsList.add(p3);
ListAdapter adapter = new SimpleAdapter(this, productsList,
R.layout.row, new String[] {"key"},
new int[] { R.id.pid});
ListView listview = getListView();
listview.setAdapter(adapter);