我在ArrayAdapter中显示我的Spinner时出现问题。它变空了我不知道为什么。错误是空指针异常。请帮我解决这个问题。这是我的代码。
package com.example.senditem;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import com.functions.ClientModel;
import com.functions.JSONParser;
import com.functions.Model;
import com.functions.MyAdapter;
import com.functions.SqliteHelper;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.StrictMode;
import android.text.InputType;
import android.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
public class UserProductActivity extends Activity {
ListView listView;
Button btnSend;
Button btnSave;
Button btnSearch;
Button btnUpload;
Spinner inputUom;
String items;
JSONParser jsonParser = new JSONParser();
ArrayAdapter<Model> adapter;
List<String> uomlist;
List<Model> list = new ArrayList<Model>();
ArrayList<ClientModel> sales = new ArrayList<ClientModel>();
private String search_product;
private String phoneNo;
ProgressDialog pDialog;
private static String upload = "http://192.168.0.101/MyAndroidConnect/upload.php";
private static String KEY_SUCCESS = "success";
private static String KEY_ITEM = "items";
private static String KEY_AGENT = "agent";
private static String KEY_DAYS = "days";
private static String KEY_BARCODE = "barcode";
private static String KEY_CLIENT = "client";
private static String KEY_QTY = "qty";
private static String KEY_UOM = "uom";
String acode;
String days;
String client;
String bcode;
String qty;
String uom;
/**
* Called when the activity is first created.
*/
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.userprodmain);
Intent i=getIntent();
final Bundle b = i.getExtras();
final SqliteHelper db = new SqliteHelper(this);
listView = (ListView) findViewById(R.id.my_list);
// btnSend = (Button) findViewById(R.id.btnSend);
btnSearch = (Button) findViewById(R.id.btnSearch);
btnSave = (Button) findViewById(R.id.btnSave);
btnUpload = (Button) findViewById(R.id.btnUpload);
inputUom = (Spinner) findViewById(R.id.inputUom);
adapter = new MyAdapter(this, getModel(), Integer.parseInt(b.get("id").toString()) );
// Toast.makeText(getBaseContext(),b.get("id").toString(),
Toast.LENGTH_LONG).show();
listView.setAdapter(adapter);
final List<String> uomlist = new ArrayList<String>();
for(int j=0;j<list.size();j++){
String barcode = list.get(j).getBar();
uomlist.add(db.selectUom(barcode));
//Toast.makeText(getBaseContext(),db.selectUom(barcode),Toast.LENGTH_SHORT).show();
}
ArrayAdapter<String> uomadapter = new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item,uomlist);
uomadapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
inputUom.setAdapter(uomadapter);
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
btnSave.setOnClickListener(new View.OnClickListener() {
public void onClick(final View v) {
listView.clearFocus();
AlertDialog.Builder alert = new AlertDialog.Builder(v.getContext());
alert.setTitle("Save Details?");
alert.setPositiveButton("Yes", new DialogInterface.OnClickListener(){
@Override
public void onClick(DialogInterface dialog, int which){
for (int i = 0; i < list.size(); i++) {
if(list.get(i).getQuantity()!=null)
{
// Toast.makeText(v.getContext(), String.valueOf(list.get(i).getprodId()), Toast.LENGTH_LONG).show();
db.addItem(new Model(Integer.parseInt(b.get("id").toString()), list.get(i).getprodId(), list.get(i).getQuantity(),list.get(i).getAmt()));
}
}
}
});
alert.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
alert.show();
}
});
btnSearch.setOnClickListener(new View.OnClickListener(){
public void onClick(final View v) {
AlertDialog.Builder alert = new AlertDialog.Builder(v.getContext());
alert.setTitle("Search Item");
final EditText input = new EditText(v.getContext());
input.setInputType(InputType.TYPE_CLASS_TEXT);
alert.setView(input);
alert.setPositiveButton("Search", new DialogInterface.OnClickListener(){
@Override
public void onClick(DialogInterface dialog, int which){
search_product = input.getText().toString();
int z=0;
for (int i = 0; i < list.size(); i++) {
if(search_product.toUpperCase().equals(list.get(i).getName().toUpperCase())){
listView.setSelection(i);
z=0;
}
else
z++;
}
if(z==list.size())
{
AlertDialog alert = new AlertDialog.Builder(v.getContext()).create();
alert.setTitle("No Data Found!");
alert.show();
}
}
});
alert.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
alert.setMessage("Input Message");
// alert.setCanceledOnTouchOutside(true);
// alert.setCancelMessage(null);
alert.show();
}
});
btnUpload.setOnClickListener(new View.OnClickListener(){
public void onClick(final View v) {
new UploadSales().execute();
}
});
}
private List<Model> getModel() {
Intent i=getIntent();
final Bundle b = i.getExtras();
SqliteHelper db = new SqliteHelper(this);
list = db.getAllProduct(b.get("clientCode").toString(),b.get("day").toString());
return list;
}
class UploadSales extends AsyncTask <String,String,String>{
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(UserProductActivity.this);
pDialog.setMessage("Uploading Sales. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
protected String doInBackground(String... params) {
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
// Check for success tag
int success;
try {
Intent i=getIntent();
final Bundle b = i.getExtras();
SqliteHelper db = new SqliteHelper(getApplicationContext());
for(int j=0; j<list.size(); j++){
acode = db.getAgent(1);
days = b.get("day").toString();
client = b.get("clientCode").toString();
bcode = list.get(j).getBar();
qty = list.get(j).getQuantity();
uom = list.get(j).getUom();
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("agent", acode));
params.add(new BasicNameValuePair("days", days));
params.add(new BasicNameValuePair("barcode", bcode));
params.add(new BasicNameValuePair("client", client));
params.add(new BasicNameValuePair("uom", uom));
params.add(new BasicNameValuePair("qty", qty));
// getting product details by making HTTP request
// Note that product details url will use GET request
JSONObject json = jsonParser.makeHttpRequest(
upload, "POST", params);
// check your log for json response
Log.d("Single Product Details", json.toString());
// json success tag
success = json.getInt(KEY_SUCCESS);
if (success == 1) {
//
}else{
// product with pid not found
}
}
} catch (JSONException e) {
e.printStackTrace();
}
}
});
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog once got all details
pDialog.dismiss();
}
}
}
这里的问题是什么？
logcat的
08-04 11:44:12.812: E/AndroidRuntime(28977): FATAL EXCEPTION: main
08-04 11:44:12.812: E/AndroidRuntime(28977): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.senditem/com.example.senditem.UserProductActivity}: java.lang.NullPointerException
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2372)
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2424)
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.app.ActivityThread.access$600(ActivityThread.java:162)
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1364)
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.os.Handler.dispatchMessage(Handler.java:107)
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.os.Looper.loop(Looper.java:194)
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.app.ActivityThread.main(ActivityThread.java:5400)
08-04 11:44:12.812: E/AndroidRuntime(28977): at java.lang.reflect.Method.invokeNative(Native Method)
08-04 11:44:12.812: E/AndroidRuntime(28977): at java.lang.reflect.Method.invoke(Method.java:525)
08-04 11:44:12.812: E/AndroidRuntime(28977): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:837)
08-04 11:44:12.812: E/AndroidRuntime(28977): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:604)
08-04 11:44:12.812: E/AndroidRuntime(28977): at dalvik.system.NativeStart.main(Native Method)
08-04 11:44:12.812: E/AndroidRuntime(28977): Caused by: java.lang.NullPointerException
08-04 11:44:12.812: E/AndroidRuntime(28977): at com.example.senditem.UserProductActivity.onCreate(UserProductActivity.java:104)
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.app.Activity.performCreate(Activity.java:5122)
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1081)
08-04 11:44:12.812: E/AndroidRuntime(28977): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2336)
08-04 11:44:12.812: E/AndroidRuntime(28977): ... 11 more
XML
<?xml version="1.0" encoding="UTF-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:id="@+id/label"
android:layout_width="90dp"
android:layout_height="wrap_content"
android:text="@+id/label"
android:textSize="15sp"/>
<TextView
android:id="@+id/inputAmt"
android:layout_width="50dp"
android:layout_height="35dp"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:layout_marginRight="22dp"
android:ems="10"
android:gravity="right"
android:inputType="number"
android:textSize="12sp" />
<EditText
android:id="@+id/inputQty"
android:layout_width="40dp"
android:layout_height="35dp"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:ems="10"
android:gravity="right"
android:inputType="number"
android:textSize="12sp" >
<requestFocus />
</EditText>
<Spinner
android:id="@+id/inputUom"
android:layout_width="40dp"
android:layout_height="35dp"
/>
</RelativeLayout>
答案 0 :(得分：0)
看到这是你的错误：
替换
adapter = new MyAdapter(this, getModel(), Integer.parseInt(b.get("id").toString()) );
// Toast.makeText(getBaseContext(),b.get("id").toString(),
Toast.LENGTH_LONG).show();
listView.setAdapter(adapter);
与
adapter = new MyAdapter(this, getModel(), Integer.parseInt(b.get("id").toString()) );
// Toast.makeText(getBaseContext(),b.get("id").toString(),
// Toast.LENGTH_LONG).show();
listView.setAdapter(adapter);
还有一个错误，我发现检查你是否在你的代码中声明了两次全局，第二次在本地声明，所以只需删除本地声明 替换
final List<String> uomlist=new ArrayList<String>()
到
uomlist=new ArrayList<String>()
多数民众赞成......