Custom QTableView width

[Cotlone]

Hey Everyone,

I have made a QTableView subclass which I wanted to resize to fit the columns within it. Basically, I cannot for the life of me figure out what I am missing here. There are an extra 11 pixels that I need to add from some header or border or something, which remains independent of the number of columns in the QTableView. There is no vertical header

I can, live the having the 11 pixels hard coded in here if I have to, but does anyone know what these pixels are accounting for?

int TableViewCopy::maximumWidthHint()
{
    int colWidth = 0;
    int count = model()->columnCount();
 
    for(int i = 0; i < count; i++)
        if(!isColumnHidden(i))
            colWidth += columnWidth(i);
 
    int tableWidth =
        (colWidth +                         // total column width
         verticalScrollBar()->height() +    // Need room for the vertical scrollbar
         11);                               // Why do I need 11 pixels to make it view correctly? (Windows7x64 Aero)
 
    return tableWidth;
}

int TableViewCopy::maximumWidthHint()
{
    int colWidth = 0;
    int count = model()->columnCount();

    for(int i = 0; i < count; i++)
        if(!isColumnHidden(i))
            colWidth += columnWidth(i);

    int tableWidth =
        (colWidth +                         // total column width
         verticalScrollBar()->height() +    // Need room for the vertical scrollbar
         11);                               // Why do I need 11 pixels to make it view correctly? (Windows7x64 Aero)

    return tableWidth;
}

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Thanks in advance for your help everyone!

- Michael

[Santosh Reddy]

Use horizontal header view to calculate the column width, then no need to account for scroll bar, use this way

int TableViewCopy::maximumWidthHint()
{
    //QHeaderView * view = header(); // use this for QTreeView
    QHeaderView * view = horizontalHeader(); // use this for QTableView
 
    int sections = view->count();
    int tableWidth = 0;
 
    for(int i = 0; i < sections; i++)
        tableWidth += view->sectionSize(i);
 
    return tableWidth;
}

int TableViewCopy::maximumWidthHint()
{
    //QHeaderView * view = header(); // use this for QTreeView
    QHeaderView * view = horizontalHeader(); // use this for QTableView
	
    int sections = view->count();
    int tableWidth = 0;
    
    for(int i = 0; i < sections; i++)
        tableWidth += view->sectionSize(i);
		
    return tableWidth;
}

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[Cotlone]

Thanks Santosh Reddy,

Implementing in this way appears to be the same as accessing the length property, as below.

int TableViewCopy::maximumWidthHint()
{
    //QHeaderView * view = header(); // use this for QTreeView
    QHeaderView * view = horizontalHeader(); // use this for QTableView
 
    return view->length();
}

int TableViewCopy::maximumWidthHint()
{
    //QHeaderView * view = header(); // use this for QTreeView
    QHeaderView * view = horizontalHeader(); // use this for QTableView

    return view->length();
}

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Either way this is not producing the desired result. The size of the QTableView is still smaller than the content by a different number of pixels (maybe 30ish). Is it likely that elsewhere my code is effecting the size that this QTableView should take? Or am I missing something simple here?

[Santosh Reddy]

I am able set the TreeView's width using this method, the width exatly fits the treeview, (I expect it to be same with tableview), may be there is somthing else in you code, which is causing this.

[d_stranz]

Does the column width include the pixels used for the grid and/or resize handles between columns? Does it include any padding between columns? Does it include the viewport margins? Frame width? Each of the base classes for QTableView applies some formatting to the view, so that could account for the missing pixels.

[Cotlone]

Santosh: Hmm, that is strange because I don't think I have really changed anything that would effect the QTableView's width.

Here is an example of how I have implemented it one of my tables.

TableViewCopy *chanDataTable = new TableViewCopy;
    chanDataTable->setModel(channelData->model);
    chanDataTable->setShowGrid(false);
    chanDataTable->setEditTriggers(QAbstractItemView::NoEditTriggers); // table can not be editted
    chanDataTable->resizeColumnsToContents();
    chanDataTable->setSortingEnabled(true);

TableViewCopy *chanDataTable = new TableViewCopy;
    chanDataTable->setModel(channelData->model);
    chanDataTable->setShowGrid(false);
    chanDataTable->setEditTriggers(QAbstractItemView::NoEditTriggers); // table can not be editted
    chanDataTable->resizeColumnsToContents();
    chanDataTable->setSortingEnabled(true);

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d_stranz: I've tried to find a relationship between the column count and the excess number of pixels, but it seems not to be existent. I had a bit of a look at ViewPorts but will probably need to investigate this further.

Thanks for the replies,
Michael

[Santosh Reddy]

looks like there is no simple straight forward solution for this, I am trying to create a custom QTreeView to find a solution for this, will post updates soon

[Santosh Reddy]

check this out

int TableViewCopy::maximumWidthHint()
{
	// Add 2 Pixels to conpensate for the view port's border rectangle
	// if custom view port is used then change this value accordingly
    return horizontalHeader()->length() + verticalHeader()->width() + 2;
}

int TableViewCopy::maximumWidthHint()
{
	// Add 2 Pixels to conpensate for the view port's border rectangle
	// if custom view port is used then change this value accordingly
    return horizontalHeader()->length() + verticalHeader()->width() + 2;
}

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[Cotlone]

Hmm, this doesn't seem to work for me either. It is strange indeed.
I'll keep looking into it when I get a little more time on my hands.

[srazi]

Oh I had this problem!
This 11px comes from default layout margin, for me 'table->x()' gives this 11px and I change it by 'QLayout::setContentsMargins(int,int,int,int)'
edit: a typo in function name!

[Cotlone]

Hi everyone, thanks for the help.

Sorry about the latency of this response, it been pretty busy here.

Anyway, I had a look for the table->x() value and it wasn't what I was after. For me, it has a value of zero.

My search continues...

Cheers,
Michael