我在我的应用程序中使用列表视图，首先我从添加按钮更新列表视图，但后来我需要选择更多项目，所以我需要移动到另一个页面来选择值，所以我使用意图并将我的值带到另一个页面在数组中，然后当我尝试在另一个页面上移动以选择更多项目时，我的应用程序由于 listview 而崩溃，我尝试了没有 listview 的程序，然后它工作正常并在 logcat 中显示我的数组。
所以，这是我的代码：-
public class selectsaloon extends Activity {
public String Salon_name, Spinnervalue, Spinnervalue1, Spinnervalue2,
Spinnervalue3, service, regular, banding, band, username, password,
percentage, total_visits, number_of_visits, total, result1,
btnvalue, salon, service1, price, visit;
public Spinner Spinner, Spinner1, Spinner2, Spinner3;
ArrayList<String> list, list1, list2, list3;
SimpleAdapter adp;
String str[], str1[], str2[], str3[], vik[], listv1[], listv2[], listv3[],
listv4[];
ListView serviceview;
JSONArray jsArray;
Integer Count, cont;
JSONObject json1, json2;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.selectsaloon);
Intent in = getIntent();
Bundle b = in.getExtras();
cont = b.getInt("count");
username = b.getString("username");
password = b.getString("password");
btnvalue = b.getString("btnvalue");
if (cont == 0) {
listv1 = b.getStringArray("Spinnervalue");
listv2 = b.getStringArray("Spinnervalue1");
listv3 = b.getStringArray("Spinnervalue2");
listv4 = b.getStringArray("Spinnervalue3");
list();
}
json();
Spinner1 = (Spinner) findViewById(R.id.spnerservice);
Spinner2 = (Spinner) findViewById(R.id.spnerprice);
Spinner3 = (Spinner) findViewById(R.id.spnerdscnt);
serviceview = (ListView) this.findViewById(R.id.serviceview);
Button btnaddmore = (Button) findViewById(R.id.btnaddmore);
// Spinner.setOnItemSelectedListener(new MyOnItemSelectedListener());
btnaddmore.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
list.add(Spinnervalue);
list1.add(Spinnervalue1);
list2.add(Spinnervalue2);
list3.add(Spinnervalue3);
str = list.toArray(new String[list.size()]);
str1 = list1.toArray(new String[list1.size()]);
str2 = list2.toArray(new String[list2.size()]);
str3 = list3.toArray(new String[list3.size()]);
Intent in = new Intent(getApplicationContext(),
selectservice1.class);
Bundle bundle1 = new Bundle();
bundle1.putInt("Count", 1);
bundle1.putString("username", username);
bundle1.putString("password", password);
bundle1.putStringArray("Spinnervalue", str);
bundle1.putStringArray("Spinnervalue1", str1);
bundle1.putStringArray("Spinnervalue2", str2);
bundle1.putStringArray("Spinnervalue3", str3);
in.putExtras(bundle1);
startActivity(in);
}
});
Button btncontinue = (Button) findViewById(R.id.btncontinue);
// Spinner.setOnItemSelectedListener(new MyOnItemSelectedListener());
btncontinue.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
String res = null;
try {
JSONObject object11 = new JSONObject();
object11.put("salon", salon);
object11.put("service", service1);
object11.put("price", price);
object11.put("visit", visit);
object11.put("username", username);
String strng = object11.toString();
object11 = executehttpost(strng);
JSONArray earthquakes = object11.getJSONArray("item");
for (int in = 0; in < 1; in++) {
JSONObject e = earthquakes.getJSONObject(in);
// String id=String.valueOf(i);
res = e.getString("flag");
}
// Toast.makeText(this, "Json Objects are : ",+ res,
// Toast.LENGTH_LONG).show();
if (res.contentEquals("OOPS! Record can't inserted")) {
Intent ourintent = new Intent(getApplicationContext(),
MainActivity.class);
startActivity(ourintent);
} else {
Intent i1 = new Intent(getApplicationContext(),
selectservice.class);
Bundle bundle = new Bundle();
bundle.putInt("count", 0);
bundle.putString("username", username);
bundle.putString("password", password);
i1.putExtras(bundle);
startActivity(i1);
}
} catch (JSONException e) {
Log.e("log_tag", "Error parsing data " + e.toString());
} catch (Exception je) {
}
// }
}
private JSONObject executehttpost(String strng) throws Exception {
// TODO Auto-generated method stub
InputStream inpstream = null;
String result = "";
JSONObject jsnarry = null;
try {
list.add(Spinnervalue);
list1.add(Spinnervalue1);
list2.add(Spinnervalue2);
list3.add(Spinnervalue3);
str = list.toArray(new String[list.size()]);
str1 = list1.toArray(new String[list1.size()]);
str2 = list2.toArray(new String[list2.size()]);
str3 = list3.toArray(new String[list3.size()]);
for (int i = 0; i < str.length - 1; i++) {
salon = str[i];
service1 = str1[i];
price = str2[i];
visit = str3[i];
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost(
"http://www.siliconsoftwares.in/griffin/jsonuserservice.php");
List<NameValuePair> value = new ArrayList<NameValuePair>(
8);
value.add(new BasicNameValuePair("salon", salon));
value.add(new BasicNameValuePair("service", service1));
value.add(new BasicNameValuePair("price", price));
value.add(new BasicNameValuePair("visit", visit));
value.add(new BasicNameValuePair("username", username));
UrlEncodedFormEntity urlentity = new UrlEncodedFormEntity(
value);
post.setEntity(urlentity);
HttpResponse response = client.execute(post);
HttpEntity resultentity = response.getEntity();
inpstream = resultentity.getContent();
}
} catch (Exception e) {
// TODO: handle exception
}
try {
BufferedReader reader = new BufferedReader(
new InputStreamReader(inpstream, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
inpstream.close();
result = sb.toString();
} catch (Exception e) {
// TODO: handle exception
}
// TODO Auto-generated method stub
try {
jsnarry = new JSONObject(result);
} catch (JSONException e) {
Log.e("log_tag", "Error parsing data " + e.toString());
}
return jsnarry;
}
});
list = new ArrayList<String>();
list1 = new ArrayList<String>();
list2 = new ArrayList<String>();
list3 = new ArrayList<String>();
Button btnadd = (Button) findViewById(R.id.btnadd);
// Spinner.setOnItemSelectedListener(new MyOnItemSelectedListener());
btnadd.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
list.add(Spinnervalue);
list1.add(Spinnervalue1);
list2.add(Spinnervalue2);
list3.add(Spinnervalue3);
str = list.toArray(new String[list.size()]);
str1 = list1.toArray(new String[list1.size()]);
str2 = list2.toArray(new String[list2.size()]);
str3 = list3.toArray(new String[list3.size()]);
String[] from = { "str", "str1", "str2", "str3" };
int[] to = { R.id.listview1, R.id.listview2, R.id.listview3,
R.id.listview4 };
List<HashMap<String, String>> fillMaps = new ArrayList<HashMap<String, String>>();
for (int i = 0; i < str.length; i++) {
HashMap<String, String> map = new HashMap<String, String>();
map.put("str", str[i]);
map.put("str1", "" + str1[i]);
map.put("str2", "" + str2[i]);
map.put("str3", "" + str3[i]);
fillMaps.add(map);
}
Log.d("bbb", "" + fillMaps);
adp = new SimpleAdapter(getBaseContext(), fillMaps,
R.layout.spinnerview, from, to);
serviceview.setAdapter(adp);
// Count = adp.getCount();
//if (Count != 0) {
//serviceview.setVisibility(View.VISIBLE);
//}
}
// }
});
}
private void list() {
// TODO Auto-generated method stub
String[] frm = { "str", "str1", "str2", "str3" };
int[] tv = { R.id.listview1, R.id.listview2, R.id.listview3,
R.id.listview4 };
List<HashMap<String, String>> fillMaps = new ArrayList<HashMap<String, String>>();
for (int i = 0; i < listv1.length-1; i++) {
HashMap<String, String> map = new HashMap<String, String>();
map.put("str", "" + listv1[i]);
map.put("str1", "" + listv2[i]);
map.put("str2", "" + listv3[i]);
map.put("str3", "" + listv4[i]);
fillMaps.add(map);
//Log.d("listv1", "" + listv1[i]);
//Log.d("listv2", "" + listv2[i]);
//Log.d("listv3", "" + listv3[i]);
//Log.d("listv4", "" + listv4[i]);
}
//Log.d("aaa", "" + fillMaps);
SimpleAdapter adapter = new SimpleAdapter(getBaseContext(), fillMaps,R.layout.spinnerview, frm, tv);
//Count = adapter.getCount();
// if (Count != 0) {
// serviceview.setVisibility(View.VISIBLE);
//}
serviceview.setAdapter(adapter);
}
private void json() {
// TODO Auto-generated method stub
JSONObject json = JSONfunctions
.getJSONfromURL("http://siliconsoftwares.in/griffin/jsonservice.php");
try {
JSONArray earthquakes = json.getJSONArray("item");
final String[] items = new String[earthquakes.length()];
for (int i = 0; i < earthquakes.length(); i++) {
JSONObject e = earthquakes.getJSONObject(i);
Salon_name = e.getString("saloon_name");
items[i] = e.getString("saloon_name");
Spinner = (Spinner) findViewById(R.id.spnersaloon);
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
selectsaloon.this, android.R.layout.simple_spinner_item,
items);
// ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
// R.layout.sp, items);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
Spinner.setAdapter(adapter);
} catch (Exception e) {
// TODO: handle exception
}
Spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view,
int pos, long id) {
Spinnervalue = parent.getItemAtPosition(pos).toString();
// if (Spinnervalue.equals("Affinity")) {
if (btnvalue.equals("cutting")) {
json1 = JSONfunctions
.getJSONfromURL("http://siliconsoftwares.in/griffin/jsonhair.php");
} else {
json1 = JSONfunctions
.getJSONfromURL("http://siliconsoftwares.in/griffin/jsonbeauty.php");
}
try {
JSONArray earthquakes1 = json1.getJSONArray("item");
final String[] items1 = new String[earthquakes1.length()];
for (int i = 0; i < earthquakes1.length(); i++) {
JSONObject e = earthquakes1.getJSONObject(i);
number_of_visits = e.getString("number_of_visits");
total_visits = e.getString("total_visits");
percentage = e.getString("percentage");
total = number_of_visits + "-" + percentage + "%";
items1[i] = total;
// Log.d("total", "" + total);
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
selectsaloon.this, R.layout.sp, items1);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
Spinner3.setAdapter(adapter);
spnr();
} catch (Exception e) {
// TODO: handle exception
}
if (btnvalue.equals("cutting")) {
json2 = JSONfunctions
.getJSONfromURL("http://siliconsoftwares.in/griffin/jsonstylist.php?saloon_name="
+ Spinnervalue + "");
} else {
json2 = JSONfunctions
.getJSONfromURL("http://siliconsoftwares.in/griffin/jsonstylist1.php?saloon_name="
+ Spinnervalue + "");
}
try {
JSONArray earthquakes1 = json2.getJSONArray("item");
final String[] items1 = new String[earthquakes1.length()];
for (int i = 0; i < earthquakes1.length(); i++) {
JSONObject e = earthquakes1.getJSONObject(i);
service = e.getString("service");
items1[i] = e.getString("service");
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
selectsaloon.this, R.layout.sp, items1);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
Spinner1.setAdapter(adapter);
spn();
} catch (Exception e) {
// TODO: handle exception
}
}
private void spnr() {
// TODO Auto-generated method stub
Spinner3.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> arg0, View arg1,
int arg2, long arg3) {
// TODO Auto-generated method stub
Spinnervalue3 = arg0.getItemAtPosition(arg2).toString();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
});
}
private void spn() {
// TODO Auto-generated method stub
Spinner1.setOnItemSelectedListener(new OnItemSelectedListener() {
public void onItemSelected(AdapterView<?> parent,
View view, int pos, long id) {
Spinnervalue1 = parent.getItemAtPosition(pos)
.toString();
// Log.d("Spinner1", "" + Spinnervalue1);
// Log.d("Spinner", "" + Spinnervalue);
String res = null;
try {
JSONObject object11 = new JSONObject();
object11.put("service", Spinnervalue1);
object11.put("saloon_name", Spinnervalue);
String strng = object11.toString();
object11 = executehttpost(strng);
JSONArray earthquakes = object11
.getJSONArray("item");
final String[] items = new String[earthquakes
.length()];
for (int i = 0; i < earthquakes.length(); i++) {
JSONObject e = earthquakes.getJSONObject(i);
regular = e.getString("regular");
banding = e.getString("banding");
band = banding + " " + "£" + regular;
items[i] = band;
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
selectsaloon.this, R.layout.sp, items);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
Spinner2.setAdapter(adapter);
spn2();
} catch (JSONException e) {
Log.e("log_tag",
"Error parsing data " + e.toString());
} catch (Exception je) {
}
}
private void spn2() {
// TODO Auto-generated method stub
Spinner2.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> arg0,
View arg1, int arg2, long arg3) {
// TODO Auto-generated method stub
Spinnervalue2 = arg0.getItemAtPosition(arg2)
.toString();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
});
}
private JSONObject executehttpost(String strng)
throws Exception {
// TODO Auto-generated method stub
InputStream inpstream = null;
String result = "";
JSONObject jsnarry = null;
try {
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost(
"http://siliconsoftwares.in/griffin/jsonprice.php");
List<NameValuePair> value = new ArrayList<NameValuePair>(
8);
value.add(new BasicNameValuePair("service",
Spinnervalue1));
value.add(new BasicNameValuePair("saloon_name",
Spinnervalue));
UrlEncodedFormEntity urlentity = new UrlEncodedFormEntity(
value);
post.setEntity(urlentity);
HttpResponse response = client.execute(post);
HttpEntity resultentity = response.getEntity();
inpstream = resultentity.getContent();
} catch (Exception e) {
// TODO: handle exception
}
try {
BufferedReader reader = new BufferedReader(
new InputStreamReader(inpstream,
"iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
inpstream.close();
result = sb.toString();
} catch (Exception e) {
// TODO: handle exception
}
// TODO Auto-generated method stub
try {
jsnarry = new JSONObject(result);
} catch (JSONException e) {
Log.e("log_tag",
"Error parsing data " + e.toString());
}
return jsnarry;
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
});
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
});
}
}
`
我的错误在这里-
private void list() {
// TODO Auto-generated method stub
String[] frm = { "str", "str1", "str2", "str3" };
int[] tv = { R.id.listview1, R.id.listview2, R.id.listview3,
R.id.listview4 };
List<HashMap<String, String>> fillMaps = new ArrayList<HashMap<String, String>>();
for (int i = 0; i < listv1.length-1; i++) {
HashMap<String, String> map = new HashMap<String, String>();
map.put("str", "" + listv1[i]);
map.put("str1", "" + listv2[i]);
map.put("str2", "" + listv3[i]);
map.put("str3", "" + listv4[i]);
fillMaps.add(map);
//Log.d("listv1", "" + listv1[i]);
//Log.d("listv2", "" + listv2[i]);
//Log.d("listv3", "" + listv3[i]);
//Log.d("listv4", "" + listv4[i]);
}
//Log.d("aaa", "" + fillMaps);
SimpleAdapter adapter = new SimpleAdapter(getBaseContext(), fillMaps,R.layout.spinnerview, frm, tv);
//Count = adapter.getCount();
// if (Count != 0) {
// serviceview.setVisibility(View.VISIBLE);
//}
serviceview.setAdapter(adapter);
}
`
我的日志猫：-
`
04-12 10:58:20.909: I/dalvikvm(1406): threadid=3: reacting to signal 3
04-12 11:17:00.720: E/AndroidRuntime(1817): FATAL EXCEPTION: main
04-12 11:17:00.720: E/AndroidRuntime(1817): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.griffinclub/com.example.griffinclub.selectsaloon}: java.lang.NullPointerException
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.app.ActivityThread.access$600(ActivityThread.java:123)
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.os.Handler.dispatchMessage(Handler.java:99)
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.os.Looper.loop(Looper.java:137)
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.app.ActivityThread.main(ActivityThread.java:4424)
04-12 11:17:00.720: E/AndroidRuntime(1817): at java.lang.reflect.Method.invokeNative(Native Method)
04-12 11:17:00.720: E/AndroidRuntime(1817): at java.lang.reflect.Method.invoke(Method.java:511)
04-12 11:17:00.720: E/AndroidRuntime(1817): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
04-12 11:17:00.720: E/AndroidRuntime(1817): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
04-12 11:17:00.720: E/AndroidRuntime(1817): at dalvik.system.NativeStart.main(Native Method)
04-12 11:17:00.720: E/AndroidRuntime(1817): Caused by: java.lang.NullPointerException
04-12 11:17:00.720: E/AndroidRuntime(1817): at com.example.griffinclub.selectsaloon.list(selectsaloon.java:341)
04-12 11:17:00.720: E/AndroidRuntime(1817): at com.example.griffinclub.selectsaloon.onCreate(selectsaloon.java:75)
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.app.Activity.performCreate(Activity.java:4465)
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
04-12 11:17:00.720: E/AndroidRuntime(1817): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
04-12 11:17:00.720: E/AndroidRuntime(1817): ... 11 more
`