view_xview += 1
I'm trying to make my screen constantly scroll, but it's not moving.
As far as I'm aware you just make an invisible object on your screen and assign this as a step event to it? I've also heard to make the camera follow an invisible object moving on the screen but this seems better surely?
I've enabled my use of views, enabled it to be seen, I've tried
view_xview += 1 and view_xview[0] += 1 because I've seen both, I'm definitely on view0.
The easiest way to do this is to make an object that's invisible but still has a sprite, and just give it an hspeed of 1, then have the view follow it. Create it a bit before the horizontal follow border so that the player can get their bearings before the screen starts moving.
Where are you placed view_xview[0] += 1? What event? Step? And Object following must be <no object>.
So, all steps must be:
Create object obj_controller
Add event Step, place code: view_xview[0] += 1;
Create room
Place obj_controller to the room
Enable views in the room (Enable the use of Views in the Views tab)
Set Visible when room starts for View 0
Define size/port of the view
Also set Use synchronization to avoid tearing in Global Game Settings -> Windows -> Graphics
Related
I am using the new unity networking using unity 5.3.1 , my player prefab is a UI canvas , so when another client joins the canvas's overlap and I cannot press any button on host or client .
What i want is to disable other canvase's on each players game and just leave the local players canvase active , I have tried islocalplayer , isclient ,isserver but nothing works .
Is there a way around this please do tell.
Here are some options I can think of:
1) Instead of making canvas a player object, make panel a player object, so that all your players are different panels under same canvas. Now, when object are under same canvas, they ray casting order is determined by the order in hierarchy.
The objects that are lower in the hierarchy occlude those that are higher. So, what you can do is moving your player object to the lowest position in objects hierarchy, so that it will occlude all other players. This can be done using Transform methods SetSiblingIndex and GetSiblingIndex, like
transform.SetSiblingIndex(100000/*some big number*/);
2) Disable raycasting on all other players - what if you can click some component on canvas or not is whether it is a raycast target. Images and Text components can be raycast targets, or more generally any component that inherits from Graphics. You can iterate over all components of type Graphics in all players except the local player and mark raycastTarget = false.
I figured it out and as #NikaKasradze said use only one canvas and put all gui listeners in the islocalplayer bool check .
This is driving me nuts. I have a custom menu class that, when set visible, shows a list of items located in a particular folder. When a hardware button is pressed, my application gets the latest list of items, populates the menu with them, and returns.
The menu displaying these items uses a QListWidget filled with custom widgets. Each of the widgets contains one or more QLabels in a horizontal layout, and is created at the time the menu is shown. In order to adjust the text displayed based on the menu width available, I need to get the size of the QLabel AFTER it has been resized according to the layout, but before the menu becomes visible to the user. The problem is, my layout does not get updated until all of the functions constructing my list return.
I have tried QApplication::ProcessEvents() and the layout update functions, but none of them have updated the values of my QLabels before returning. I can set a QTimer when the button is initially pressed, and have it show the menu, update the items, and stop itself, but that seems like a terrible solution.
Any help would really be appreciated! I've spent most of a day on this.
Marlon
I had this exact problem and could not find an answer anywhere on the Internet. Calling Layout.update(), Layout.activate(), or widget.adjustSize() (all suggested in various places) all did not work.
I had a widget with a vertical layout that I wanted to add a QLabel to and then immediately use the size of the QLabel.
The only thing that worked reliably was
layout->addWidget(myLabel);
myLabel->show();
size = myLabel->size();
It would seem that layouts will just not recalculate until you either return from a function and allow the Qt event loop to progress or manually call show() yourself.
How to update a QLayout and get the new dimensions before returning?
Don't. You're not meant to do that. It'll drive you "nuts" because you're doing it backwards. Layout updates are handled asynchronously from the event loop. Instead of getting layout dimensions right away, set yourself up to be part of the system. Some options are:
Implement a custom widget that will interact properly with the layout, growing to fill the available width of the layout. Perhaps all you need is a size policy and a way to elide text?
Make a custom layout that takes the special properties of your use case into account.
You want to call QWidget::adjustSize() on your parent widget. This will force the layout recalculations.
Have you tried using layout()->update(); ?
I've tried many but nothing works for me on Qt 5.15.
Only invented little patch - create timer and get size after 20 msec:
QTimer::singleShot(20, this, [this]
{
const auto height = myLayout->contentsRect().height();
// ...
});
I'm implementing Qt's drag and drop API across Windows and X. When I pick up an object in the app running on X and drag it, it leaves a white ghost trail of itself on the window underneath, as if the window underneath is being slow to repaint where the dragged object was previously obscuring part of itself.
I believe that this is symptomatic of the same problem that Qt has just solved with resizing windows causing flicker in child widgets on X windows - i.e. the dragged object is treated as a separate native window and therefore X handles the clipping from the dragged object to the window underneath. Since X does this in a different way to Qt, we get the ghosting effect.
Has anyone experienced the same problems? One solution that comes to mind is to use the same technique as detailed in the blog article linked above and stop the dragged object being treated as a native window, presumably at the cost of drag and drop being limited to my application only (I have no problem with this). Would anyone know how to force drag and drop operations to be internal only?
EDIT: I'm using QDrag::setPixmap to set the graphical representation of the dragged object - it is important that I retain this in favour of a standard drag cursor as this interface is being used on a touchscreen device and will hence have no visible cursor.
I'm now of the opinion that short of editing and then compiling my own build of Qt (not an option for me), I can't force drag and drop operations to be internal only.
Equally, I can't find any way of getting rid of the ghost trail by tweaking my window manager settings or using a compositing window manager (thanks anyway though #atomice). Using OpenGL as the renderer increases the screen repaint speed slightly, but is not perfect and introduces its own problems (see Starting a Qt drag operation on X11 w/ OpenGL causes screen flicker). I would still be very interested to hear any ideas though.
I have, however, got a workaround for my problem which works on both Windows and X. Here's a simplified version:
void DoDrag()
{
//Prepare the graphical representation of the drag
mDragRepresenter = new QWidget(QApplication::activeWindow());
mDragRepresenter->setAttribute(Qt::WA_TransparentForMouseEvents);
mDragRepresenter->SetPixmap(GenerateDragPixmap());
RepositionDragRepresenter();
mDragRepresenter->show();
QTimer UpdateTimer;
connect(&UpdateTimer, SIGNAL(timeout()), this, SLOT(RepositionDragRepresenter()));
UpdateTimer.start(40);
//Start the drag (modal operation)
Qt::DropAction ResultingAction = Drag->exec(Qt::CopyAction);
UpdateTimer.stop();
delete mDragRepresenter;
}
void RepositionDragRepresenter()
{
mDragRepresenter->move(QApplication::activeWindow()->mapFromGlobal(QCursor::pos()) - mDragRepresenterHotSpot);
}
An X11 window is only created for a drag operation if a QDrag::mimeData()->hasImage() is true. If you modify your code so it doesn't use an image then you will just get a drag cursor instead which won't trigger a repaint of the windows underneath.
You don't specify what kind of object you are dragging or how you are setting up the drag operation. Can you add some code to show that?
Hai,
I am trying to create a chess board. Here I want to do a operation like when ever a coin is clicked and dragged, at that time that picture should be copied and be placed in that old position. I don't know in which function I have to do it. When I made it on mouse pressed, then tyhe copy is coming above the original(layer wise). So somebody please help me
When I made it on mouse pressed, then tyhe copy is coming above the original(layer wise).
When you got this far, simply adding a call to myItemCopy->setZValue( -1 ) would place the copy "behind" the original item.
A different approach, and possibly "cleaner", would be to use QDrag and tell Qt how to paint your item during the Drag operation. See Qt's "Drag and Drop Robot" example for reference: http://doc.qt.io/qt-5/qtwidgets-graphicsview-dragdroprobot-example.html
Happy coding!
Robin
Simplest way to do this will be to put 2 identical QGraphicsItems for each coin/piece at the same location. The top one will be dragged and moved while the bottom one will stay for the visual cue you want.
Once the top one is dropped to the new location, move the bottom one there too.
Is there any way to attach two Qt windows together? For example, if window A is the main window and window B is another widget I want to be able to show window B to the side of A and have both windows move together if the windows are dragged.
Not that I am aware of, but you can try following the trail of QMoveEvent. When a given widget is moved void QWidget::moveEvent ( QMoveEvent * event ) is called, and the QMoveEvent contains both old and new pos. Using this information, you can inject a move event in the other widget as well, and make it follow.
Of course, I am speaking of two independent widgets, each one in its own window. If they are contained, you don't need anything but a Layout management (see QLayout and related classes).
I don't work with Qt since a long time, so there could be a better method, but if I had to do it right now, this is the strategy I would use.
Also, I have the feeling that the QMoveEvent will be invoked only at start and end, unless you enable mouse tracking. If the former is the case, you will obtain that the other widget will "teleport" at the end of the move, instead of following smoothly.
You might be after something like this:
http://doc.qt.io/archives/4.6/qt4-mainwindow.html
Window A would be a QMainWindow and window B would be a QDockWidget.