QTableView 的 qt setItem 导致 "program not responding"
qt setItem for QTableView causes "program not responding"
我在向 qt creator
中的 table 添加值时遇到问题
在我下面的代码中,我有一个函数可以将数据从数据库插入 table。
QSqlQuery q;
//counts the number of rows that contain the value acicn
q.prepare("select count(*) from checkdata where acic_num=:acicn");
q.bindValue(":acicn", acicn);
q.exec();
int rowtablecount = 0;
if(q.next()){
rowtablecount = q.value(0).toInt();
//using value acicn, inserts into the table the number of rows found in database
QAbstractItemModel *mdl;
mdl = ui->editEntry_tbl->model();
mdl->insertRows(0,rowtablecount);
}else{
qDebug() << "table error in edit entry";
}
q.finish();
QSqlQuery q2;
q2.prepare("select *from acic where acic_num=:acicnum");
q2.bindValue(":acicnum", acicn);
q2.exec();
//above extracts data from database table acic, below from table checkdata
q.prepare("select * from checkdata where acic_num=:acicnum");
q.bindValue(":acicnum", acicn);
q.exec();
QStandardItemModel *model;
QString temp;
while(q.next()){
for(int r=0; r<rowtablecount-1; r++){
temp =q.value(6).toString(); //date paid
QStandardItem *cellFiller8 = new QStandardItem(temp);
model->setItem(r,10,cellFiller8); //<<--- PART WHERE PROGRAM FAILS AND HANGS, SHOWING PROGRAM NOT RESPONDING
temp =q.value(5).toString(); //amount of check
QStandardItem *cellFiller6 = new QStandardItem(temp);
model->setItem(r,7,cellFiller6);
temp =q.value(4).toString(); //account code
QStandardItem *cellFiller5 = new QStandardItem(temp);
model->setItem(r,6,cellFiller5);
temp =q.value(3).toString(); //particulars
QStandardItem *cellFiller4 = new QStandardItem(temp);
model->setItem(r,5,cellFiller4);
temp =q.value(2).toString(); //payee name
QStandardItem *cellFiller3 = new QStandardItem(temp);
model->setItem(r,4,cellFiller3);
temp =q.value(1).toString(); //alobs
QStandardItem *cellFiller2 = new QStandardItem(temp);
qDebug() << temp;
model->setItem(r,3,cellFiller2);
temp =q.value(0).toString(); //check number
QStandardItem *cellFiller1 = new QStandardItem(temp);
qDebug() << temp;
model->setItem(r,2,cellFiller1);
}
}
while(q2.next()){
for(int r=0; r<rowtablecount-1; r++){
temp =q2.value(3).toString(); //amount of acic
QStandardItem *cellFiller7 = new QStandardItem(temp);
model->setItem(r,8,cellFiller7);
temp =q2.value(0).toString(); //check date
QStandardItem *cellFiller = new QStandardItem(temp);
qDebug() << "before setitem" << temp;
model->setItem(r,1,cellFiller);
qDebug() << "after setItem";
}
}
基本上,使用model->setItem(r,1,cellFiller)
会导致程序挂起。我发现这非常令人困惑,因为我多次使用相同的方法填写 QTableView
,但这是第一次发生这种情况。
知道为什么会这样吗?
您忘记初始化 QStandardItemModel *model
变量。
我在向 qt creator
中的 table 添加值时遇到问题在我下面的代码中,我有一个函数可以将数据从数据库插入 table。
QSqlQuery q;
//counts the number of rows that contain the value acicn
q.prepare("select count(*) from checkdata where acic_num=:acicn");
q.bindValue(":acicn", acicn);
q.exec();
int rowtablecount = 0;
if(q.next()){
rowtablecount = q.value(0).toInt();
//using value acicn, inserts into the table the number of rows found in database
QAbstractItemModel *mdl;
mdl = ui->editEntry_tbl->model();
mdl->insertRows(0,rowtablecount);
}else{
qDebug() << "table error in edit entry";
}
q.finish();
QSqlQuery q2;
q2.prepare("select *from acic where acic_num=:acicnum");
q2.bindValue(":acicnum", acicn);
q2.exec();
//above extracts data from database table acic, below from table checkdata
q.prepare("select * from checkdata where acic_num=:acicnum");
q.bindValue(":acicnum", acicn);
q.exec();
QStandardItemModel *model;
QString temp;
while(q.next()){
for(int r=0; r<rowtablecount-1; r++){
temp =q.value(6).toString(); //date paid
QStandardItem *cellFiller8 = new QStandardItem(temp);
model->setItem(r,10,cellFiller8); //<<--- PART WHERE PROGRAM FAILS AND HANGS, SHOWING PROGRAM NOT RESPONDING
temp =q.value(5).toString(); //amount of check
QStandardItem *cellFiller6 = new QStandardItem(temp);
model->setItem(r,7,cellFiller6);
temp =q.value(4).toString(); //account code
QStandardItem *cellFiller5 = new QStandardItem(temp);
model->setItem(r,6,cellFiller5);
temp =q.value(3).toString(); //particulars
QStandardItem *cellFiller4 = new QStandardItem(temp);
model->setItem(r,5,cellFiller4);
temp =q.value(2).toString(); //payee name
QStandardItem *cellFiller3 = new QStandardItem(temp);
model->setItem(r,4,cellFiller3);
temp =q.value(1).toString(); //alobs
QStandardItem *cellFiller2 = new QStandardItem(temp);
qDebug() << temp;
model->setItem(r,3,cellFiller2);
temp =q.value(0).toString(); //check number
QStandardItem *cellFiller1 = new QStandardItem(temp);
qDebug() << temp;
model->setItem(r,2,cellFiller1);
}
}
while(q2.next()){
for(int r=0; r<rowtablecount-1; r++){
temp =q2.value(3).toString(); //amount of acic
QStandardItem *cellFiller7 = new QStandardItem(temp);
model->setItem(r,8,cellFiller7);
temp =q2.value(0).toString(); //check date
QStandardItem *cellFiller = new QStandardItem(temp);
qDebug() << "before setitem" << temp;
model->setItem(r,1,cellFiller);
qDebug() << "after setItem";
}
}
基本上,使用model->setItem(r,1,cellFiller)
会导致程序挂起。我发现这非常令人困惑,因为我多次使用相同的方法填写 QTableView
,但这是第一次发生这种情况。
知道为什么会这样吗?
您忘记初始化 QStandardItemModel *model
变量。