[Solved] Remove items from Layout

[donitaroid]

I wrote a program which receive the some test result from internet. The test result I received have to be displayed on the QWidget.

Here is the design I have imagined: I can clear all items in the QVBoxLayout, and then fill the new content what I have received.

I wrote some code according the logic above, and it does not work as what I thought. The executing screen shot:
!http://img829.imageshack.us/img829/2040/removeitemfromlayout.png(::executing screen shot::)!

It leaves some.... shadow or the items should be already remove all sqeezed in the first row.

Is there any problem with my code?

@

int totalCount = ui->resultTextContainerLayout->count();
for (int i = 0; i < totalCount; i++) {
    ui->resultTextContainerLayout->removeItem(ui->resultTextContainerLayout->itemAt(0));
}
//ui->resultTextContainerLayout->invalidate();

for (int i = 0 ; i < eBoxDiskNum ; i++) {
    QLabel* tempLabel = new QLabel(ui->resultTextContainer);
    tempLabel->setFont(QFont("Calibri", 12));
    if (iErrCode & (1 << i)) {
        tempLabel->setStyleSheet("QLabel {color:red;}");
        tempLabel->setText(QString("Client%1 -> not ready").arg(i+1));
    } else {
        tempLabel->setStyleSheet("QLabel {color:black;}");
        tempLabel->setText(QString("Client%1 -> ready").arg(i+1));
    }
    ui->resultTextContainerLayout->addWidget(tempLabel);
}
ui->resultTextContainerLayout->addStretch();

@

[lgeyer]

QLayout::removeItem() just removes the item from layout, but does not hide or delete it.
@
QLayoutItem *item;
while ((item = ui->resultTextContainerLayout->takeAt(0)) != 0) {
delete item;
}

for (int i = 0 ; i < eBoxDiskNum ; i++) {
...
@

Be aware that the above code only works for non-nested layouts (layouts only containing widgets). If you add nested layouts to your layout you will need a recursive removal. See "this":http://qt-project.org/forums/viewthread/13583/#71685 thread for further information.

[donitaroid]

Yes, it works.

There are some difference between the code I tested which is I delete it using widget()

@
QLayoutItem *item = NULL;
while ((item = ui->resultTextContainerLayout->takeAt(0)) != 0) {
delete item->widget();
}
@

Thank you very much

[lgeyer]

Be aware that not every item must be a widget! Your code actually works because <code>delete 0</code> is allowed in C++.

[bird_alone]

use this to clear all items inside a layout...

@void clearLayout(QLayout *layout)
{
QLayoutItem *child;
while ((child = layout->takeAt(0)) != 0) {
if(child->layout() != 0)
clearLayout( child->layout() );
else if(child->widget() != 0)
delete child->widget();

    delete child;
}

}@