我的应用执行以下操作:
-输入员工姓名，点击搜索按钮。
-作为结果的匹配名称列表。
-点击其中一个结果名称。
-一个新的 Activity 打开，点击的名字，它的标题，电话，显示的电子邮件数据。
但是，当我单击其中一个结果名称时，我的应用程序崩溃了，它没有显示任何错误。
这是我到目前为止所做的。
public class MainActivity extends Activity
{
EditText name;
ArrayAdapter<String> nameAdapter;
DeptDPHelper Emp;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final Button Search = (Button)findViewById(R.id.Search);
name = (EditText)findViewById(R.id.name);
final ListView namelist = (ListView)findViewById(R.id.LV);
nameAdapter = new ArrayAdapter<>(getApplicationContext() , android.R.layout.simple_list_item_1);
namelist.setAdapter(nameAdapter);
Emp = new DeptDPHelper(getApplicationContext());
//Inserting some data into database
Emp.InsertEmp("AhmedMhmmd" , "010224455" , "gg@jj.com" , "xx");
Emp.InsertEmp("MhmmdMhmoud" , "010224455" , "gg@jj.com" , "xx");
Emp.InsertEmp("Ahmedxxx" , "010224455" , "gg@jj.com" , "xx");
Emp.InsertDept("Finance");
Emp.InsertDept("Sales");
//Search button
Search.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v) {
Cursor cur = Emp.GetEmpname(name.getText().toString());
nameAdapter.clear();
if(cur != null)
{
while(!cur.isAfterLast())
{
//Toast.makeText(getApplicationContext() , "Error" , Toast.LENGTH_LONG).show();
nameAdapter.add(cur.getString(0));
cur.moveToNext();
//nameAdapter.add("gg");
}
}
else
{
Toast.makeText(getApplicationContext() , "ErrOooor" , Toast.LENGTH_LONG).show();
}
}
});
//When clicking a name from the list of results.
namelist.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id)
{
String name = namelist.getItemAtPosition(position).toString(); //get the name
Cursor empID = Emp.getEmpID(name); //pass the name to a method to get its ID
Cursor DepID = Emp.getDeptID(name);
empID.moveToFirst();
DepID.moveToFirst();
int eID = empID.getInt(0); //Converting ID into Integer
int dID = DepID.getInt(0);
Intent intent = new Intent(MainActivity.this, empDetails.class);
intent.putExtra("empName", Emp.getEmpData(eID).toString()); //getting value of name using ID
intent.putExtra("empTitle",Emp.getEmpData(eID).toString());
intent.putExtra("empPhone",Emp.getEmpData(eID).toString());
intent.putExtra("empEmail",Emp.getEmpData(eID).toString());
intent.putExtra("empDept",Emp.getDeptName(dID).toString());
startActivity(intent);
}
});
}
//SQLITE Part
public static class DeptDPHelper extends SQLiteOpenHelper {
SQLiteDatabase EmpDept;
public DeptDPHelper(Context context) {
super(context, "EmpDept", null, 2);
}
@Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL("create table department(DeptID integer primary key autoincrement , name text);");
db.execSQL("create table Employee (EmpID integer primary key autoincrement , name text not null," +
"Title text not null , phone text not null , email text not null ," +
"DeptID integer, foreign key(DeptID) references department (DeptID))");
//ContentValues row = new ContentValues();
//db.execSQL("insert into Employee (EmpID , name , Title , phone , email ) values ('Ahmemhmmd' , '010224455' , 'gg@jj.com' , 'xx')");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("drop table if exists department ");
db.execSQL("drop table if exists Employee ");
onCreate(db);
}
public void InsertEmp (String Empname, String phone, String Email, String title)
{
ContentValues roww = new ContentValues();
//roww.put("Id",empID );
roww.put("name", Empname);
roww.put("Title", title);
roww.put("phone", phone);
roww.put("Email", Email);
EmpDept = getWritableDatabase();
EmpDept.insert("Employee ", null, roww);
EmpDept.close();
}
public void InsertDept(String Deptname)
{
ContentValues row = new ContentValues();
//row.put("Id", DeptID);
row.put("name", Deptname);
EmpDept = getWritableDatabase();
EmpDept.insert("department ", null, row);
EmpDept.close();
}
public Cursor GetEmpname(String namee)
{
EmpDept = getReadableDatabase();
String[] arg = {namee};
Cursor cur = EmpDept.rawQuery("select name from employee where name like ?;", new String[]{"%"+namee+"%"});
cur.moveToFirst();
EmpDept.close();
return cur;
}
public Cursor Fetchallemployee() {
EmpDept = getReadableDatabase();
String[] rowdetails = {"name"};
Cursor cursor = EmpDept.query("employee", rowdetails, null
, null, null, null, null);
if (cursor != null) {
cursor.moveToFirst();
}
EmpDept.close();
return cursor;
}
//This method in order to get the employee id using the clicked name
public Cursor getEmpID(String nameList)
{
EmpDept = getReadableDatabase();
String[] rowID = {nameList};
Cursor cursor = EmpDept.rawQuery("select EmpID from Employee where name like ?",rowID);
EmpDept.close();
if (cursor != null)
{
cursor.moveToFirst();
}
return cursor;
}
public Cursor getDeptID(String nameList)
{
EmpDept = getReadableDatabase();
String[] rowwID = {nameList};
Cursor curr = EmpDept.rawQuery("select DeptID from department inner join Employee on department.DeptID = Employee.DeptID where Employee.name like ? ",rowwID);
//department d inner join Employee e on d.DeptID = e.DeptID where e.name like ?
if (curr != null)
{
curr.moveToFirst();
}
EmpDept.close();
return curr;
}
//This method for returning employee data using employee id as an input
public Cursor getEmpData(Integer employeeID)
{
EmpDept = getReadableDatabase();
// String[] empRow = {"name", "title", "phone", "Email"};
//String[] arg = {name, title, phone, email};
Integer[] empRow = {employeeID};
//Cursor c = EmpDept.query("Employee", empRow, null, null, null, null, null);
Cursor c = EmpDept.rawQuery("Select name, Title, phone, email from Employee where EmpID like ?", new String[]{employeeID.toString()});
if (c != null)
{
c.moveToFirst();
}
EmpDept.close();
return c;
}
public Cursor getDeptName(Integer departmentID)
{
EmpDept = getReadableDatabase();
Integer[] deptRow = {departmentID};
//Cursor cr = EmpDept.rawQuery("Select name from department d inner join Employee e on d.DeptID = e.DeptID where e.name like ?",new String[]{deptartmentID.toString()});
Cursor cr = EmpDept.rawQuery("Select name from department where DeptID like ?",new String[]{departmentID.toString()});
if (cr != null)
{
cr.moveToFirst();
}
EmpDept.close();
return cr;
}
}
}
当我输入一个名字并点击搜索按钮时，它起作用了，我得到了名字列表，但是当我点击其中一个名字时，它崩溃了。
这里出了什么问题？
这是我的日志:
11-27 04:39:48.835 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:39:48.835 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:39:58.905 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:39:58.905 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:08.975 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:08.975 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:09.665 704-1339/? E/Watchdog: !@Sync 6712 [11-27 04:40:09.670]
11-27 04:40:10.695 13974-13989/? E/ContactsProvider_EventLog: Flush buffer to file cnt : 1 size : 0Kb duration : 1ms lastUpdatedAfter : 60117 ms mFlush_time_threasold : 2000 mCurrentSize : 294
11-27 04:40:19.045 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:19.045 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:21.025 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.025 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.275 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.315 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.315 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.315 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.435 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.435 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.495 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.595 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.655 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.705 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.775 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.775 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.895 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:21.955 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:22.015 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:22.035 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:22.035 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:22.045 220-225/? E/Tzdaemon: [w2] pthread_setaffinity_np() failed: 22
11-27 04:40:29.095 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:712,format:0
11-27 04:40:29.095 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:712,format:0
11-27 04:40:30.465 3733-3733/? E/AffinityControl: AffinityControl: registerfunction enter
11-27 04:40:39.175 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:39.175 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:39.235 2767-2767/? E/MtpServerJNI: server is null in send_object_removed
11-27 04:40:39.665 704-1339/? E/Watchdog: !@Sync 6713 [11-27 04:40:39.672]
11-27 04:40:49.245 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:49.245 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:59.315 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:40:59.315 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:09.385 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:09.385 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:09.665 704-1339/? E/Watchdog: !@Sync 6714 [11-27 04:41:09.673]
11-27 04:41:10.825 13974-13989/? E/ContactsProvider_EventLog: Flush buffer to file cnt : 1 size : 0Kb duration : 2ms lastUpdatedAfter : 60131 ms mFlush_time_threasold : 2000 mCurrentSize : 294
11-27 04:41:19.465 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:19.465 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:29.535 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:29.535 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:29.775 704-876/? E/MARsDBManager: updateDBAll : begin --size 1
11-27 04:41:29.815 704-876/? E/MARsDBManager: updateDBAll : end
11-27 04:41:39.605 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:39.605 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:39.665 704-1339/? E/Watchdog: !@Sync 6715 [11-27 04:41:39.674]
11-27 04:41:49.675 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:49.675 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:59.745 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:41:59.745 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:09.665 704-1339/? E/Watchdog: !@Sync 6716 [11-27 04:42:09.675]
11-27 04:42:09.815 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:09.815 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:10.955 13974-13989/? E/ContactsProvider_EventLog: Flush buffer to file cnt : 1 size : 0Kb duration : 3ms lastUpdatedAfter : 60123 ms mFlush_time_threasold : 2000 mCurrentSize : 294
11-27 04:42:19.895 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:19.895 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:29.965 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:29.965 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:38.625 1547-32615/? E/Places: ?: Exceeded maximum network back off time, fetching nearby places failed with status: 7
11-27 04:42:39.665 704-1339/? E/Watchdog: !@Sync 6717 [11-27 04:42:39.676]
11-27 04:42:40.035 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:40.035 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:50.105 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:42:50.105 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:00.175 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:00.175 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:09.675 704-1339/? E/Watchdog: !@Sync 6718 [11-27 04:43:09.678]
11-27 04:43:10.245 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:10.245 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:11.065 13974-13989/? E/ContactsProvider_EventLog: Flush buffer to file cnt : 1 size : 0Kb duration : 1ms lastUpdatedAfter : 60110 ms mFlush_time_threasold : 2000 mCurrentSize : 294
11-27 04:43:20.315 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:20.315 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:30.395 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:30.395 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:39.675 704-1339/? E/Watchdog: !@Sync 6719 [11-27 04:43:39.679]
11-27 04:43:40.465 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:40.465 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:50.535 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:43:50.535 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:00.605 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:00.605 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:09.675 704-1339/? E/Watchdog: !@Sync 6720 [11-27 04:44:09.680]
11-27 04:44:10.675 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:10.675 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:11.185 13974-13989/? E/ContactsProvider_EventLog: Flush buffer to file cnt : 1 size : 0Kb duration : 1ms lastUpdatedAfter : 60116 ms mFlush_time_threasold : 2000 mCurrentSize : 294
11-27 04:44:20.745 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:20.745 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:30.815 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:30.815 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:39.675 704-1339/? E/Watchdog: !@Sync 6721 [11-27 04:44:39.681]
11-27 04:44:40.895 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:40.895 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:50.965 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:44:50.965 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:45:01.035 326-1009/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
11-27 04:45:01.035 217-291/? E/NetlinkEvent: NetlinkEvent::decode(): buffer'change@/devices/battery/power_supply/battery' size:713,format:0
这是我的 empDetails Activity 代码:
public class empDetails extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_emp_details);
TextView name = (TextView)findViewById(R.id.textView7);
TextView title = (TextView)findViewById(R.id.textView8);
TextView phone = (TextView)findViewById(R.id.textView9);
TextView email = (TextView)findViewById(R.id.textView10);
TextView dept = (TextView)findViewById(R.id.textView11);
name.setText(getIntent().getExtras().getString("empName"));
title.setText(getIntent().getExtras().getString("empTitle"));
phone.setText(getIntent().getExtras().getString("empPhone"));
email.setText(getIntent().getExtras().getString("empEmail"));
dept.setText(getIntent().getExtras().getString("empDept"));
}
}
当我调试时，调试器部分什么都不显示，控制台部分的一部分显示如下:
--------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.fatma.assgnment004, PID: 2580
java.lang.IllegalStateException: Cannot perform this operation because the connection pool has been closed.
at android.database.sqlite.SQLiteConnectionPool.throwIfClosedLocked(SQLiteConnectionPool.java:962)
at android.database.sqlite.SQLiteConnectionPool.waitForConnection(SQLiteConnectionPool.java:599)
at android.database.sqlite.SQLiteConnectionPool.acquireConnection(SQLiteConnectionPool.java:348)
at android.database.sqlite.SQLiteSession.acquireConnection(SQLiteSession.java:894)
at android.database.sqlite.SQLiteSession.executeForCursorWindow(SQLiteSession.java:834)
at android.database.sqlite.SQLiteQuery.fillWindow(SQLiteQuery.java:62)
at android.database.sqlite.SQLiteCursor.fillWindow(SQLiteCursor.java:143)
at android.database.sqlite.SQLiteCursor.getCount(SQLiteCursor.java:132)
at android.database.AbstractCursor.moveToPosition(AbstractCursor.java:219)
at android.database.AbstractCursor.moveToFirst(AbstractCursor.java:258)
at com.example.fatma.assgnment004.MainActivity$DeptDPHelper.getEmpID(MainActivity.java:182)
at com.example.fatma.assgnment004.MainActivity$2.onItemClick(MainActivity.java:77)
at android.widget.AdapterView.performItemClick(AdapterView.java:310)
at android.widget.AbsListView.performItemClick(AbsListView.java:1156)
at android.widget.AbsListView$PerformClick.run(AbsListView.java:3121)
at android.widget.AbsListView.onTouchUp(AbsListView.java:4048)
at android.widget.AbsListView.onTouchEvent(AbsListView.java:3807)
at android.view.View.dispatchTouchEvent(View.java:10023)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2626)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2307)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2632)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2321)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2632)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2321)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2632)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2321)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2632)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2321)
at com.android.internal.policy.DecorView.superDispatchTouchEvent(DecorView.java:413)
at com.android.internal.policy.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1808)
at android.app.Activity.dispatchTouchEvent(Activity.java:3061)
at com.android.internal.policy.DecorView.dispatchTouchEvent(DecorView.java:375)
at android.view.View.dispatchPointerEvent(View.java:10243)
at android.view.ViewRootImpl$ViewPostImeInputStage.processPointerEvent(ViewRootImpl.java:4438)
at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:4306)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3853)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3906)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3872)
at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3999)
at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3880)
at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:4056)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3853)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3906)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3872)
at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3880)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3853)
at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:6246)
at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:6220)
at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:6181)
at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:6349)
E/AndroidRuntime: at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:185)
at android.os.MessageQueue.nativePollOnce(Native Method)
at android.os.MessageQueue.next(MessageQueue.java:323)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Disconnected from the target VM, address: 'localhost:8647', transport: 'socket'
最佳答案
已编辑
已添加到问题的堆栈跟踪中有一行内容为
java.lang.IllegalStateException: Cannot perform this operation because the connection pool has been closed.
这表示连接(可能有一个数字，因此连接池)已关闭。连接是到数据库的连接。它已关闭，因为您已经使用 EmpDept.close() 专门关闭了它。
创建 Cursor 时，它实际上并不包含数据，而是在需要数据时从数据库中读取数据。如果数据库已关闭，则无法获取数据。
例如你有:-
cur.moveToFirst();
EmpDept.close(); //<<<<<<<<<< Database connection closed
return cur;
简而言之，您不能关闭数据库连接然后访问 Cursor 中的数据。
这是一个完整的工作解决方案，不包括上述缺陷或其他缺陷(一些由评论指出)。
首先在 Employee.java
中创建一个名为 Employee 的新类public class Employee {
private long employeeId;
private String employeeName;
private String employeeTitle;
private String employeePhone;
private String employeeEmail;
private long employeeDeptId;
private String employeeDeptName;
public Employee(
long id,
String name,
String title,
String phone,
String email,
long deptid,
String deptname
) {
this.employeeId = id;
this.employeeName = name;
this.employeeTitle = title;
this.employeePhone = phone;
this.employeeEmail = email;
this.employeeDeptId = deptid;
this.employeeDeptName = deptname;
}
public Employee() {
this(-1L,"","","","",-1L,"");
}
public Employee(String name, String title, String phone, String email) {
this(-1L,name,title,phone,email,-1L,"");
}
public long getEmployeeId() {
return employeeId;
}
public void setEmployeeId(long employeeId) {
this.employeeId = employeeId;
}
public String getEmployeeName() {
return employeeName;
}
public void setEmployeeName(String employeeName) {
this.employeeName = employeeName;
}
public String getEmployeeTitle() {
return employeeTitle;
}
public void setEmployeeTitle(String employeeTitle) {
this.employeeTitle = employeeTitle;
}
public String getEmployeePhone() {
return employeePhone;
}
public void setEmployeePhone(String employeePhone) {
this.employeePhone = employeePhone;
}
public String getEmployeeEmail() {
return employeeEmail;
}
public void setEmployeeEmail(String employeeEmail) {
this.employeeEmail = employeeEmail;
}
public long getEmployeeDeptId() {
return employeeDeptId;
}
public void setEmployeeDeptId(long employeeDeptId) {
this.employeeDeptId = employeeDeptId;
}
public String getEmployeeDeptName() {
return employeeDeptName;
}
public void setEmployeeDeptName(String employeeDeptName) {
this.employeeDeptName = employeeDeptName;
}
public boolean ifFullyUseableEmployee() {
return this.employeeId < 1 || this.employeeDeptId < 1 || this.employeeDeptName.length() < 1;
}
@Override
public String toString() {
return this.employeeTitle + " " + this.employeeName;
}
}
可能是 DatabaseHelper 的新类，即 DeptDPhelper.java
public class DeptDPHelper extends SQLiteOpenHelper {
SQLiteDatabase EmpDept;
//<<<<<<<<<< BAD PRACTICE TO HARD CODE TABLE AND COLUMN NAMES THROUGHOUT >>>>>>>>>>
//<<<<<<<<<< INSTEAD USE CONSTANTS >>>>>>>>>>>
public static final String DBNAME = "EmpDept";
public static final int DBVERSION = 2;
public static final String DEPARTMENT_TABLE = "department";
public static final String EMPLOYEE_TABLE = "employee"; //<<<<<<<<<< not Employee to be consistent with naming connvention
public static final String DEPARTMENT_DEPTID_COLUMN = "departmenttid";
public static final String DEPARTMENT_NAME_COLUMN = "departmentname";
public static final String EMPLOYEE_EMPID_COLUMN = "employeeid";
public static final String EMPLOYEE_NAME_COLUMN = "employeename";
public static final String EMPLOYEE_TITLE_COLUMN= "employeetitle";
public static final String EMPLOYEE_PHONE_COLUMN = "employeephone";
public static final String EMPLOYEE_EMAIL_COLUMN = "employeeemail";
public static final String EMPLOYEE_DEPT_COLUMN = "employeeedepartmentid";
public DeptDPHelper(Context context) {
super(context, DBNAME, null, DBVERSION);
EmpDept = this.getWritableDatabase();
}
@Override
public void onCreate(SQLiteDatabase db) {
String crt_dept_table_sql = "CREATE TABLE IF NOT EXISTS " + DEPARTMENT_TABLE + "(" +
DEPARTMENT_DEPTID_COLUMN + " INTEGER PRIMARY KEY, " + //<<<<<<<<<< AUTOINCREMENT INEFFICIENT NOT NEEDED
DEPARTMENT_NAME_COLUMN + " TEXT" +
")";
db.execSQL(crt_dept_table_sql);
String crt_employee_table_sql = "CREATE TABLE IF NOT EXISTS " + EMPLOYEE_TABLE + "(" +
EMPLOYEE_EMPID_COLUMN + " INTEGER PRIMARY KEY, " +
EMPLOYEE_NAME_COLUMN + " TEXT NOT NULL, " +
EMPLOYEE_TITLE_COLUMN + " TEXT NOT NULL, " +
EMPLOYEE_PHONE_COLUMN + " TEXT NOT NULL, " +
EMPLOYEE_EMAIL_COLUMN + " TEXT NOT NULL, " +
EMPLOYEE_DEPT_COLUMN + " INTEGER REFERENCES " + DEPARTMENT_TABLE + "(" +
DEPARTMENT_DEPTID_COLUMN +
")" +
")";
db.execSQL(crt_employee_table_sql);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
//<<<<<<<<<< IF USING FOREIGN KEYS AND SUPPORT IS ON THEN CANNOT DELETE PARENT TABLE FIRST >>>>>>>>>>
//<<<<<<<<<< AS SUCH DEPARTMENT TABLE MUST BE DROPPED FIRST OTHEWISE THERE WILL BE CONFLICTS >>>>>>>>>>
db.execSQL("DROp TABLE IF EXISTS " + EMPLOYEE_TABLE);
db.execSQL("DROP TABLE IF EXISTS " + DEPARTMENT_TABLE);
onCreate(db);
}
//<<<<<<<<<< FOREIGN KEY SUPPORT IS TUREND OFF BY DEFAULT SO TURN THEM ON >>>>>>>>>>
//<<<<<<<<<< IF NOT USELESS CODING FOREIGN KEYS >>>>>>>>>>
@Override
public void onConfigure(SQLiteDatabase db) {
db.setForeignKeyConstraintsEnabled(true);
super.onConfigure(db);
}
public long insertEmployee(String name, String title, String phone, String email, long deptid) {
//<<<<<<<<<< optional check if deptid references a deptartment >>>>>>>>>>
//<<<<<<<<<< however INSERT OR IGNORE doesn't ignore FK conflicts >>>>>>>>>>
if (!ifDepertmentExists(deptid)) return -1;
ContentValues cv = new ContentValues();
cv.put(EMPLOYEE_NAME_COLUMN,name);
cv.put(EMPLOYEE_TITLE_COLUMN,title);
cv.put(EMPLOYEE_PHONE_COLUMN,phone);
cv.put(EMPLOYEE_EMAIL_COLUMN,email);
cv.put(EMPLOYEE_DEPT_COLUMN,deptid);
return EmpDept.insert(EMPLOYEE_TABLE,name,cv);
}
public long insertDepartment(String name) {
ContentValues cv = new ContentValues();
cv.put(DEPARTMENT_NAME_COLUMN,name);
return EmpDept.insert(DEPARTMENT_TABLE,null,cv);
}
public Cursor selectLikeEmployeesByNamePart(String namepart) {
String[] columns = new String[]{EMPLOYEE_NAME_COLUMN};
String whereclause = EMPLOYEE_NAME_COLUMN + "LIKE ?";
String[] whereargs = new String[] {"%" + namepart +"%"};
return EmpDept.query(EMPLOYEE_TABLE,columns,whereclause,whereargs,null,null,EMPLOYEE_NAME_COLUMN);
}
public ArrayList<Employee> getAllEmployees(String namepart) {
ArrayList<Employee> employees = new ArrayList<>();
String whereclause = null;
String[] wherargs = null;
if (namepart != null && namepart.length() > 0) {
whereclause = EMPLOYEE_NAME_COLUMN + " LIKE ?";
wherargs = new String[]{"%" + namepart + "%"};
}
Cursor csr = EmpDept.query(EMPLOYEE_TABLE + " JOIN " + DEPARTMENT_TABLE + " ON " + EMPLOYEE_DEPT_COLUMN + "=" + DEPARTMENT_DEPTID_COLUMN,
null,whereclause, wherargs, null, null, EMPLOYEE_NAME_COLUMN + "," + EMPLOYEE_DEPT_COLUMN);
while (csr.moveToNext()) {
employees.add( new Employee(
csr.getLong(csr.getColumnIndex(EMPLOYEE_EMPID_COLUMN)),
csr.getString(csr.getColumnIndex(EMPLOYEE_NAME_COLUMN)),
csr.getString(csr.getColumnIndex(EMPLOYEE_TITLE_COLUMN)),
csr.getString(csr.getColumnIndex(EMPLOYEE_PHONE_COLUMN)),
csr.getString(csr.getColumnIndex(EMPLOYEE_EMAIL_COLUMN)),
csr.getLong(csr.getColumnIndex(DEPARTMENT_DEPTID_COLUMN)),
csr.getString(csr.getColumnIndex(DEPARTMENT_NAME_COLUMN)))
);
}
csr.close();
return employees;
}
private boolean ifDepertmentExists(long deptid) {
String wherecluase = DEPARTMENT_DEPTID_COLUMN + "=?";
String[] whereargs = new String[]{String.valueOf(deptid)};
Cursor csr =EmpDept.query(DEPARTMENT_TABLE,null,wherecluase,whereargs,null,null,null);
int rowcount = csr.getCount();
csr.close();
return rowcount > 0;
}
}
- 添加了一些评论，应该可以解释一些事情。
empDetails Activity 即empDetails.java
public class empDetails extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_emp_details);
TextView name = (TextView)findViewById(R.id.textview7);
TextView title = (TextView)findViewById(R.id.textview8);
TextView phone = (TextView)findViewById(R.id.textview9);
TextView email = (TextView)findViewById(R.id.textview10);
TextView dept = (TextView)findViewById(R.id.textview11);
Button mDoneButton = this.findViewById(R.id.donebutton);
mDoneButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
finish();
}
});
name.setText(getIntent().getExtras().getString(DeptDPHelper.EMPLOYEE_NAME_COLUMN));
title.setText(getIntent().getExtras().getString(DeptDPHelper.EMPLOYEE_TITLE_COLUMN));
phone.setText(getIntent().getExtras().getString(DeptDPHelper.EMPLOYEE_PHONE_COLUMN));
email.setText(getIntent().getExtras().getString(DeptDPHelper.EMPLOYEE_EMAIL_COLUMN));
dept.setText(getIntent().getExtras().getString(DeptDPHelper.DEPARTMENT_NAME_COLUMN));
}
}
最后是MainActivity.java
public class MainActivity extends AppCompatActivity {
DeptDPHelper mDBHlpr;
ArrayList<Employee> mEmployeeList;
ArrayAdapter mNameAdapter;
ListView namelist;
EditText mNamePart;
TextWatcher mTW;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
namelist = this.findViewById(R.id.namelist);
mNamePart = this.findViewById(R.id.searchbar);
mDBHlpr = new DeptDPHelper(this);
addSomeData();
setupOrRefreshNameList();
setupSearch();
}
private void setupOrRefreshNameList() {
String namepart = mNamePart.getText().toString();
if (namepart.length() < 1) namepart = null;
if (mEmployeeList != null) {
mEmployeeList.clear();
ArrayList<Employee> el = mDBHlpr.getAllEmployees(namepart);
mEmployeeList.addAll(el);
} else {
mEmployeeList = mDBHlpr.getAllEmployees(namepart);
}
if (mNameAdapter == null) {
mNameAdapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,mEmployeeList);
namelist.setAdapter(mNameAdapter);
setupListViewListeners();
} else {
mNameAdapter.notifyDataSetChanged();
}
}
//<<<<<<<<<< For testing >>>>>>>>>>
private void addSomeData() {
long dept1 = mDBHlpr.insertDepartment("Dept001");
long dept2 = mDBHlpr.insertDepartment("Dept002");
mDBHlpr.insertEmployee("Fred","Mr.","1234567890","fred.x.com",dept1);
mDBHlpr.insertEmployee("Fred","Mr.","0987654321","fred@z.com",dept2);
mDBHlpr.insertEmployee("Mary","Ms.","9999999999","mary@marymail.net",dept1);
mDBHlpr.insertEmployee("Albert","Sir ", "1113334445","lord@roayls.org",dept1);
}
private void setupListViewListeners() {
namelist.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Employee e = (Employee) mNameAdapter.getItem(i);
Toast.makeText(
getApplicationContext(),
"You clicked on " +
e.getEmployeeTitle() + " " +
e.getEmployeeName() +
" ID=" + String.valueOf(e.getEmployeeId()) +
" Email=" + e.getEmployeeEmail() +
" Phone=" + e.getEmployeePhone() +
" Dept=" + e.getEmployeeDeptName()
,
Toast.LENGTH_SHORT)
.show();
Intent intent = new Intent(MainActivity.this,empDetails.class);
intent.putExtra(DeptDPHelper.EMPLOYEE_NAME_COLUMN,e.getEmployeeName());
intent.putExtra(DeptDPHelper.EMPLOYEE_EMPID_COLUMN,e.getEmployeeId());
intent.putExtra(DeptDPHelper.EMPLOYEE_TITLE_COLUMN,e.getEmployeeTitle());
intent.putExtra(DeptDPHelper.EMPLOYEE_PHONE_COLUMN,e.getEmployeePhone());
intent.putExtra(DeptDPHelper.EMPLOYEE_EMAIL_COLUMN,e.getEmployeeEmail());
intent.putExtra(DeptDPHelper.DEPARTMENT_NAME_COLUMN,e.getEmployeeDeptName());
startActivity(intent);
}
});
}
private void setupSearch() {
mTW = new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
//<<<<<<<<<< Every time the text is changed refresh the ListView >>>>>>>>>>
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
setupOrRefreshNameList();
}
@Override
public void afterTextChanged(Editable editable) {
}
};
mNamePart.addTextChangedListener(mTW);
}
}
请注意，当您在 EditText 中输入文本时，这会动态更改列表
注意 Mainifest 包含
<activity android:name=".empDetails"></activity>
第一次运行时你会得到:-
例如输入A(注意仅适用于名称而不适用于标题部分):-
点击玛丽:-
完成后会返回 MainActivity。
关于java - 单击 ListView 中的项目时，Android 应用程序崩溃，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/53491888/