Installation and getting started with first app

andre

"control variables"? You mean you need a pointer to them?

@
m_ui->myCoolLineEdit->setText("I'm so cool!");
@

works for me. myCoolLineEdit is of course the name you gave the widget in Designer, and m_ui is the member variable that holds the UI class you created.

KennedyDayala

excellent..now i understood this part Andre..I have creaed a QTreeWidget on my MainWindow and coded like tihs..

@
ui->treeWidgetDrives = new QTreeWidget();
ui->treeWidgetDrives->setColumnCount(1);
QStringList strlstHeaders;
strlstHeaders<<tr("Storage Drives");
ui->treeWidgetDrives->setHeaderLabels(strlstHeaders);
@

...when i run my code nothing is happened to my TreeWidget(no header is assigned)..instead it is showing the properties which i set from 'Edit Tree Widget' dialog !!!

[EDIT: code formatting, please use @-tags, Volker]

goetz

The tree widget is automatically created for you. Just remove the first line of your snippet.

KennedyDayala

if i remove that line and run the code I am not getting my Window displayed and here is the ouput..

Starting E:\Bose\Qt playground\IDT_Demo_UI-build-desktop\debug\IDT_Demo_UI.exe...
E:\Bose\Qt playground\IDT_Demo_UI-build-desktop\debug\IDT_Demo_UI.exe exited with code -1073741819

goetz

code -1073741819 = 0xC0000005. On windows this means an access violation. Seems like your UI is not initialized properly or messed up in some way....

KennedyDayala

perfect analysis..

I have moved this line to bottom of the code like this..

@
IDT_MainWindow::IDT_MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::IDT_MainWindow)

{
// my code here...

    ui->setupUi(this);

}
@

now i moved it to top and works fine..thanks a ton

[EDIT: code formatting, please use @-tags or the editor button, Volker]

KennedyDayala

only one child item is being shown to my TreeWidget..please look into my code and lemme know where I went wrong !!

@IDT_MainWindow::IDT_MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::IDT_MainWindow)

{
ui->setupUi(this);

ui->treeWidgetDrives->setColumnCount(1);
QStringList strlstHeaders;
strlstHeaders<<tr("Storage Drives");
ui->treeWidgetDrives->setHeaderLabels(strlstHeaders);

SetupTreeItems();

}
void IDT_MainWindow::SetupTreeItems()
{
QTreeWidgetItem *treeItems = new QTreeWidgetItem(ui->treeWidgetDrives);
treeItems->setText(0,tr("SystemDrives"));
QTreeWidgetItem *treeChildItems = new QTreeWidgetItem(treeItems);
QDir dir;
dir.setFilter(QDir::Drives);

QFileInfoList roots = dir.drives();

for(int i=0 ; i<roots.count() ; ++i)
{
    QFileInfo fiDrives = roots.at(i);
    QString strDrive = fiDrives.absoluteFilePath();
    treeChildItems->setText(i,strDrive);
}

}@

goetz

You must create a new item in your loop. You just overwrite the on you have in each iteration.

andre

Your loop keeps on updating the text of the same tree item. Do you really expect to see more of them then?

KennedyDayala

you mean like this ??

@for(int i=0 ; i<roots.count() ; ++i)
{
treeChildItems = new QTreeWidgetItem(treeItems);
QFileInfo fiDrives = roots.at(i);
QString strDrive = fiDrives.absoluteFilePath();
treeChildItems->setText(i,strDrive);
}@

goetz

[quote author="Thomas Kennedy" date="1301584395"]you mean like this ??

@for(int i=0 ; i<roots.count() ; ++i)
{
treeChildItems = new QTreeWidgetItem(treeItems);
QFileInfo fiDrives = roots.at(i);
QString strDrive = fiDrives.absoluteFilePath();
treeChildItems->setText(i,strDrive);
}@
[/quote]

You can try it to get the answer :-)

KennedyDayala

tried...it added an 'empty item' at 0th position,and 'c:' at 1st..and no more :-(

andre

So... you need to aquire some debugging skills... Just try to follow what happens in your code. Don't guess: measure instead. Try for instance to insert statements like this at every relevant point in your function, and look at the output:

@
qDebug() << LINE;
@

KennedyDayala

:-)) ok..will do that..

goetz

Of course you must have an empty first entry, because you create this one outside your loop (line 21 in your original code snippet).

This is the compactified working version:

@
void FancyClass::populate() {
ui->treeWidget->setColumnCount(1);
QStringList headers;
headers << "Storage Device";
ui->treeWidget->setHeaderLabels(headers);

QTreeWidgetItem *rootItem = new QTreeWidgetItem(ui->treeWidget);
rootItem->setText(0, "SystemDevice");

foreach(QFileInfo drive, QDir::drives()) {
    QTreeWidgetItem *driveItem = new QTreeWidgetItem(rootItem);
    driveItem->setText(0, drive.absoluteFilePath());
}

}
@

andre

/me is thinking that instead of building a tree like that himself, he would use a QFileSystemModel instead...

KennedyDayala

thanks a lot...I will try with QFileSystemModel too..

KennedyDayala

"The program can't start because mingwm10.dll is missing from your computer.Try reinstalling the program to fix this problem."

..i am getting this error when i tried running my application in stand alone mode...any help ??

giesbert

YOu are startin g without QtCreator, right?

Did you try to search the forum for answers?

see this "post":http://developer.qt.nokia.com/forums/viewthread/4869

KennedyDayala

yes Gerolf..I searched..everybody says that we need to set the invironment varioables..I did that too but of no use..