In Qt, I have created a QGraphicsScene as shown below.
m_scene = new QGraphicsScene(0,0,152,720);
m_view = new QGraphicsView(m_scene);
Now the window is created with horizontal and vertical scrollbars. Since I don’t want to use horizontal scroll bar, it used the code
m_view->setHorizontalScrollBarPolicy (Qt::ScrollBarAlwaysOff);
But at this time, there is no horizontal scrollbar and the width is not 150, it is 140 something. How to get accurate width without horizontal scrollbar?
If you want to get the inner width of your QGraphicsView, you can simply subtract the width of the scrollbar from the total width. This is how I would do it:
int innerWidth = width();
if (verticalScrollBar()) innerWidth -= verticalScrollBar()->width();
Related
I need to set the Min, Max and Pref width of the Pane contained inside of a ScrollPane to a single value (preferably the size of the ScrollPane's available viewing area).
If I just bind it to ScrollPane width, once the Scrollbar appears on the ScrollPane it overlays some of the underlying pane.
Is it possible to somehow determine the available width inside of the ScrollPane(i.e. full width minus the Scrollbar width) and monitor it for changes?
I just found the answer. I can use the scrollPane.viewportBoundsProperty()
I'm creating a UI. Right now I'm working on generic boxs that dynamically add and remove scrollbars as they are resized.
I draw the scrollbars along the bottom and right inside edge. The inside edge is important.
So at some point the box is resized. If it's resized I check to see if the new size is smaller than the size needed for the contents, if so, scroll bars are added.
My problem stems from when only one scrollbar is needed; and the size for the other dimensions/axis is very close to the size needed for the contents.
What happens is that this scrollbar is drawn on the inside edge. Now that removes area that can be used for the contents. The problem is then that if a scrollbar is shown I would have to check the area available again to see if the other scrollbar is needed. And then again.
This seems like a recursive problem; but I'm not sure how it will help me.
Some code:
void Box::UpdateVisibleRegion()
{
// if the dimensions of this box is smaller than what the widget needs, display horizontal scrollbar
if(GetDimensions().x < m_widget->GetDimensions().x)
{
m_scrollbarH->SetVisibility(true);
m_scrollbarH->SetSize(utils::coord<int>(GetDimensions().x,m_scrollbarH->GetDimensions().y));
}
else
{
m_scrollbarH->SetVisibility(false);
}
// likewise for vertical scrollbar
if(GetDimensions().y < m_widget->GetDimensions().y)
{
m_scrollbarV->SetVisibility(true);
m_scrollbarV->SetSize(utils::coord<int>(m_scrollbarV->GetDimensions().x,GetDimensions().y));
}
else
{
m_scrollbarV->SetVisibility(false);
}
And there's the problem. If the height of the box is just over the widgets height; and the width is far under it; then the horizontal scrollbar is displayed. But now the check for vertical scroll bar should have been:
if(GetDimensions().y - m_scrollbarH->GetDimensions().y < m_widget->GetDimensions().y)
Because the scrollbar is drawn on the inside edge, there's less room. But obviously I can't know that until I've checked the other. And both the horizontal and vertical are going to affect each other.
I'm sure recursion is the answer; but I can't see it.
I could probably do this with one or two big nested if statements...
I have an widget x with fixed size. Then at first I took a QScrollArea and then a QGridLayout which I set as the layout of scrollAreaWidgetContent. Then I started adding some widget x in the layout at (0,0), (0,1), (1,0), (1,1)... of grid layout. Then when I ran the program, strangely when I shrink the window vertically, the widgets overlap.
And as expected, when I increase the window size vertically, they are not overlapped anymore.
But strange thing is this problem does not occurring when I shrink window horizontally. For example,
My question is, why this is happening and more importantly, keeping in mind I want to use gridlayout, how to solve this problem?
As you said in your question:
Your widget has a fixed size, so the layout does not shrink them when there is no space left.
So the question is: what do you want to happen when you shrink the window?
If you want to shrink your widget you have to change the sizePolicy of your widgets from "Fixed" to "Preferred".
If you want to reduce the number of widgets in the layout, then you could add an event handler in the resize event and remove them
If you want to disallow the shrinking of the window, then you need to set the sizePolicy of the scrollarea to a fixed or minimumSize
I'm new to JavaFX and I want to learn. I have a Group containing a GridPane that contains a lineChart, TableView and HBox (status bar) but I'm experiencing the following problem:
I am using screen resolution 800 x 600 on Windows XP when I change the screen resolution to 1024 x 768, the lineChart, TableView and HBox does not expand to fill the new window size, it leaves a large space at the right. How can I make controls fill the width of the window when window is resized.
The TableView's height extends beyond the boundary of the window, the bottom border of the tableView and the status bar is not showing. How can I make sure that the tableView does not extend beyond the window height?
How can I make controls fill the width of the window when window is resized.
Instead of using a Group as the root of your Scene, just make the GridPane the root of your scene.
The layout Pane classes automatically expand and shrink to fit their available area as the area changes whereas a Group does not.
How can I make sure that the tableView does not extend beyond the window height?
Your scene will probably end up being completely enclosed in the window if you just make the change above and use a layout pane as the scene root.
Additionally, if the sum of the minimum sizes of the window elements is greater than the window size, then the TableView will extend beyond the boundaries of the window, in which case you can either reduce the minimum sizes of elements (by using smaller fonts or less text, explicitly setting minWidth/minHeight values etc.) or wrap elements in a ScrollPane - but in your case those modifications are probably unnecessary.
you should use userComputed size (height,and width) property.
I'm having trouble using the layout manager system with Qt. This is going to be a Symbian app, so it should resize to different devices.
This is done by using the Layouts.
On the image below I used the Vertical Layout, but I don't understand how I can decide how much each cell should take in width and height.
I want the blue to be a top label background, but I don't want it to be as high as it is now.
Does anyone know how I can do this? (I'm new to Qt :))
You can set the maximum size for a widget by right clicking it and selecting 'Size Constraints'. Under that menu you can find actions that allow you to set the current displayed size as the maximum / minimum size for vertical / horizontal or both directions.
You can also set the numbers by hand by selecting the widget and by setting the number in the 'Property Editor'. They should be under the QWidget properties.
You cannot set the Height of a vertical layout directly, but you can set the height of the widget in which the vertical layout is.
If you want to split your Widgets so that the top widget takes 33.33% of the space, use the Stretch values. Set the top widget to 1 and the bottom widget to 2.