我正在实现一个Activity带有button“珠宝和配饰”的文本。当我传递按钮的文本并触发Intent它时，它会导致NullPointerException另一个Activity？该怎么办？任何帮助将不胜感激。提前致谢。
public class Listing extends ListActivity {
/** Button to provide advance search functionality. */
TextView Paging;
String tit[];
String price1[];
String brand[];
String value;
String pst;
TextView text;
List<ListRowData> listData;
String priceAtPosition;
String typeAtPosition;
String brandAtPosition;
ProgressDialog dialog1;
ProgressDialog dialog;
AlertDialog alert;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.item_listing_page);
Intent intent = getIntent();
savedInstanceState = intent.getExtras();
value = savedInstanceState.getString("value");
priceAtPosition = savedInstanceState.getString("priceAtPosition");
typeAtPosition = savedInstanceState.getString("typeAtPosition");
brandAtPosition = savedInstanceState.getString("brandAtpositoion");
BottomBarActivity logoBar = (BottomBarActivity)
findViewById(R.id.bottomBarLayout);
logoBar.setActivity(this);
TextView txAreaName = (TextView) findViewById(R.id.areaName);
txAreaName.setText("Shop");
text = (TextView) findViewById(R.id.list_heading);
text.setText(value);
LoginScreenData loginScreenData = new LoginScreenData();
pst = loginScreenData.getPst();
Paging = (TextView) findViewById(R.id.textPage);
Button refine = (Button) findViewById(R.id.bt_refine);
refine.setOnClickListener(btClickListener);
Button sort = (Button) findViewById(R.id.bt_sort);
sort.setOnClickListener(btClickListener);
Button btnSearch = (Button) findViewById(R.id.bt_search);
btnSearch.setOnClickListener(btSearchListener);
String Latest1 = "Latest";
listData = new ArrayList<ListRowData>();
methodApiCall(pst, Latest1);
// Get the intent, verify the action and get the query
Intent in = getIntent();
in.putExtra("value", value);
if (Intent.ACTION_SEARCH.equals(in.getAction())) {
String query = in.getStringExtra(SearchManager.QUERY);
methodApiSearchCall(pst, query);
}
}
private void methodApiSearchCall(String pst2, String query) {
List<ListRowData> listData;
listData = new ArrayList<ListRowData>();
String envelope1 = "<req>" + "<term>" + query + "</term>" + "</req>";
SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME1);
request.addProperty("requestXml", envelope1);
SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(
SoapEnvelope.VER11);
envelope.setOutputSoapObject(request);
HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);
Object response = null;
String searchReference[] = null;
String eventSearchResponse = null;
String searchImg[] = null;
String searchTitle[] = null;
try {
androidHttpTransport.call(SOAP_ACTION1, envelope);
response = envelope.getResponse();
eventSearchResponse = response.toString();
} catch (Exception e) {
e.printStackTrace();
}
try {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new InputSource(new StringReader(
eventSearchResponse)));
// normalize the document
doc.getDocumentElement().normalize();
NodeList nodelistDet = doc.getElementsByTagName("det");
for (int j = 0; j < nodelistDet.getLength(); j++) {
Node node1 = nodelistDet.item(0);
Element fstelement1 = (Element) node1;
NodeList lnlist = fstelement1.getElementsByTagName("ln");
searchReference = new String[lnlist.getLength()];
searchImg = new String[lnlist.getLength()];
searchTitle = new String[lnlist.getLength()];
for (int i = 0; i < lnlist.getLength(); i++) {
Element lnelement2 = (Element) lnlist.item(i);
searchReference[i] = lnelement2.getAttribute("ref");
searchImg[i] = lnelement2.getAttribute("img");
searchTitle[i] = lnelement2.getAttribute("tit");
}
}
} catch (Exception e) {
e.printStackTrace();
}
for (int i = 0; i < searchTitle.length; i++) {
ListRowData rowData = new ListRowData();
rowData.setSearchReference(searchReference[i]);
rowData.setSearchImg(searchImg[i]);
rowData.setSearchTitle(searchTitle[i]);
listData.add(rowData);
}
method(listData);
}
public void methodApiCall(String pstcode, String latest) {
List<ListRowData> listData = new ArrayList<ListRowData>();
String envelope1 = "<req>" + "<pst>" + pstcode + "</pst>" + "<sort>"
+ latest + "</sort>" + "<dept>WOMEN</dept>" + "<cat>" + value
+ "</cat>" + "<prmax>" + priceAtPosition + "</prmax>"
+ "<brand>" + brandAtPosition + "</brand>" + "<pp>10</pp>"
+ "<inx>1</inx>" + "</req>";
SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME);
request.addProperty("requestXml", envelope1);
SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(
SoapEnvelope.VER11);
envelope.setOutputSoapObject(request);
HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);
Object response = null;
String[] description = null;
String salePrice[] = null;
String reference[] = null;
String image[] = null;
String shopSearchResponse = null;
try {
androidHttpTransport.call(SOAP_ACTION, envelope);
response = envelope.getResponse();
shopSearchResponse = response.toString();
} catch (Exception e) {
e.printStackTrace();
}
try {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new InputSource(new StringReader(
shopSearchResponse)));
// normalize the document
doc.getDocumentElement().normalize();
NodeList rootnode = doc.getElementsByTagName("resp");
Node node = rootnode.item(0);
Element fstelement = (Element) node;
NodeList reglist = fstelement.getElementsByTagName("cnt").item(0)
.getChildNodes();
Node nvalue = (Node) reglist.item(0);
NodeList reglist1 = fstelement.getElementsByTagName("pp").item(0)
.getChildNodes();
Node nvalue1 = (Node) reglist1.item(0);
NodeList reglist2 = fstelement.getElementsByTagName("inx").item(0)
.getChildNodes();
Node nvalue2 = (Node) reglist2.item(0);
String count = nvalue.getNodeValue();
String index = nvalue2.getNodeValue();
String perPage = nvalue1.getNodeValue();
Paging.setText(index + " - " + perPage + " out of " + count);
NodeList nodelist = doc.getElementsByTagName("det");
for (int j = 0; j < nodelist.getLength(); j++) {
Node node1 = nodelist.item(0);
Element fstelement1 = (Element) node1;
NodeList lnlist = fstelement1.getElementsByTagName("ln");
description = new String[lnlist.getLength()];
tit = new String[lnlist.getLength()];
salePrice = new String[lnlist.getLength()];
reference = new String[lnlist.getLength()];
price1 = new String[lnlist.getLength()];
brand = new String[lnlist.getLength()];
image = new String[lnlist.getLength()];
for (int i = 0; i < lnlist.getLength(); i++) {
Element lnelement = (Element) lnlist.item(i);
description[i] = lnelement.getAttribute("desc");
tit[i] = lnelement.getAttribute("tit");
salePrice[i] = lnelement.getAttribute("sale");
reference[i] = lnelement.getAttribute("ref");
price1[i] = lnelement.getAttribute("price");
brand[i] = lnelement.getAttribute("brand");
image[i] = lnelement.getAttribute("img");
}
}
} catch (Exception e) {
e.printStackTrace();
}
for (int i = 0; i < tit.length; i++) {
ListRowData rowData = new ListRowData();
rowData.setDescription(description[i]);
rowData.setNew_Price(salePrice[i]);
rowData.setOld_Price(price1[i]);
rowData.setTitle(tit[i]);
rowData.setImage(image[i]);
listData.add(rowData);
}
TextView totalitem = (TextView) findViewById(R.id.tx_totalItem);
totalitem.setText(Integer.toString(tit.length) + " Items");
ListView lv = getListView(); // Getting list view to activity
setListAdapter(new ListCustomAdapter(this,
R.layout.shop_list_items_row, listData));
// sets onItemClick event on list item
lv.setOnItemClickListener(itemClickListener);
}
private OnClickListener btSearchListener = new OnClickListener() {
public void onClick(View view) {
Intent in = new Intent();
in.putExtra("value", value);
onSearchRequested();
}
};
/** OnClickListener instance to perform onClick on buttons. */
private OnClickListener btClickListener = new OnClickListener() {
public void onClick(View v) {
Intent myIntent;
if (v.getId() == R.id.bt_refine) {
myIntent = new Intent().setClass(getApplicationContext(),
RefinePageActivity.class);
myIntent.putExtra("title", tit);
myIntent.putExtra("price", price1);
myIntent.putExtra("brand", brand);
myIntent.putExtra("value1", value);
startActivity(myIntent);
}
else if (v.getId() == R.id.bt_sort) {
final String items[] = { "Latest", "Title", "Price" };
AlertDialog.Builder builder = new AlertDialog.Builder(
Listing.this);
builder.setTitle("Pick a Item for sort");
builder.setSingleChoiceItems(items, -1,
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int item) {
listData = new ArrayList<ListRowData>();
methodApiCall("Default", items[item]);
alert.dismiss();
dialog1 = ProgressDialog.show(Listing.this,
"loading please wait",
"Loading. Please wait...", true);
new Thread() {
public void run() {
try {
// performBackgroundProcess1();
sleep(3000, 000);
} catch (Exception e) {
Log.e("tag", e.getMessage());
}
// dismiss the progress dialog
dialog1.dismiss();
}
}.start();
}
});
alert = builder.create();
alert.show();
}
}
};
void method(List<ListRowData> ll) {
setListAdapter(new ListCustomAdapterShopSearch(this,
R.layout.events_search_list_item_row, ll));
ListView lv1 = getListView();
lv1.setOnItemClickListener(itemClickListener);
}
/** OnItemClickListener instance to perform itemClick event on items. */
private OnItemClickListener itemClickListener = new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
final int position, long id) {
dialog = ProgressDialog.show(view.getContext(),
"loading please wait", "Loading. Please wait...", true);
new Thread() {
public void run() {
try {
Intent inDetail = new Intent().setClass(
getApplicationContext(), DetailPage.class);
inDetail.putExtra("Position", position);
startActivity(inDetail);
} catch (Exception e) {
Log.e("tag", e.getMessage());
}
// dismiss the progress dialog
dialog.dismiss();
}
}.start();
}
};
}
日志输出：
05-24 12:02:49.232: E/AndroidRuntime(849): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.capstrov/commerce.app.lib.shop.Listing}: java.lang.NullPointerException
05-24 12:02:49.232: E/AndroidRuntime(849): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
05-24 12:02:49.232: E/AndroidRuntime(849): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
05-24 12:02:49.232: E/AndroidRuntime(849): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
05-24 12:02:49.232: E/AndroidRuntime(849): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
05-24 12:02:49.232: E/AndroidRuntime(849): at android.os.Handler.dispatchMessage(Handler.java:99)
05-24 12:02:49.232: E/AndroidRuntime(849): at android.os.Looper.loop(Looper.java:123)
05-24 12:02:49.232: E/AndroidRuntime(849): at android.app.ActivityThread.main(ActivityThread.java:4627)
05-24 12:02:49.232: E/AndroidRuntime(849): at java.lang.reflect.Method.invokeNative(Native Method)
05-24 12:02:49.232: E/AndroidRuntime(849): at java.lang.reflect.Method.invoke(Method.java:521)
05-24 12:02:49.232: E/AndroidRuntime(849): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-24 12:02:49.232: E/AndroidRuntime(849): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-24 12:02:49.232: E/AndroidRuntime(849): at dalvik.system.NativeStart.main(Native Method)
05-24 12:02:49.232: E/AndroidRuntime(849): Caused by: java.lang.NullPointerException
05-24 12:02:49.232: E/AndroidRuntime(849): at commerce.app.lib.shop.Listing.methodApiCall(Listing.java:280)
05-24 12:02:49.232: E/AndroidRuntime(849): at commerce.app.lib.shop.Listing.onCreate(Listing.java:110)
05-24 12:02:49.232: E/AndroidRuntime(849): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
05-24 12:02:49.232: E/AndroidRuntime(849): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
05-24 12:02:49.232: E/AndroidRuntime(849): ... 11 more