Move qgraphicsitem Can you modify it to allow the ellipse to move? I got close by using the setFlag(QGraphicsItem::ItemIsMovable,true) and setFlag(QGraphicsItem::ITemIsSelectable,true) and also used the mapToScene(shape()) and mapToScene(rect()) before sending those parameters to the renderBackground function, but it And I draw the rectangle with text using painter on some QGraphicsItem object and then we draw it on the scene: pPainter->drawText(RectF, Qt::AlignCenter, strText); Note: I cannot modify the code above, only to add something. However, it seems this causes the item to move with a I copied some code snippets and made my own version of it. QGraphicsItem class is the base class for all graphical items in a PySide. a QGraphicsItem A which is passed as parent to QGraphicsItem B which is passed as parent to QGraphicsItem C (except the difference in coordinate system interpretation)? I was under the assumption that in case of a parent child relationship the child would be moved together with the parent if QGraphicsItem::ItemIsMovable is set for the parent. Move QGraphicsItem only when pressing inside the shape. Move QGraphicsItem to QGraphicsItemGroup position. How to use itemChange from QGraphicsItem in Qt. When this value changes the transformations scheduled at that step are performed. But why the rect is moving itself on the right side of the window? The x coordinate 100 should make the rect move at the middle according to the Scene's size. g. But when children are selected and I move the parent children move weirdly (I would like them to behave the same way as if they were not selected - move relative to their parent). I am using QGraphicsItem, and then start by implementing its two pure virtual public. Mouse Event Detection inconsistent with customized QGraphicsItem in pyqtgraph plot. Qt drawing can be very quick if you understand how it works, even if you want to draw, for example, 1000 fish all moving independently. Move RedItem when I click and drag BlueItem. You may have to register before you can post: click the register link above to proceed. The easiest solution is to set a big enough scene at the beginning as suggested here. Greetings. the vertical) direction as shown in the diagram below, where the vertical movement of the item B (shown by a red arrow) is shared by items A, C and D, but not its horizontal movement (which is shown by the blue arrows). Commented Apr 8, 2015 at 12:31. 1 Reply Last reply . Artifacts showing when modifying a custom QGraphicsItem. The value of boundinRect() is printed for every mouse move while the RectItem is moved around the scene. I have a QGraphicsScene and a few QGraphicsItem objects on it. 3. At best, I can get the rectangle to When The children are not selected and I move the parent everything's fine - they keep their positions relative to the parent and move with it. I create an QGraphicsRectItem and set the ItemIsMovable attribute. Modified 1 year, 7 months ago. e leftclick + move). How do you restrict a QGraphicsItem to move horizontally or vertically? For example, If an item is at (0,0), how do I restrict the movement between (0,0)-(150,0)? For this you need to subclass QGraphicsScene and re-implement mouseMoveEvent. This might be a very uninformed question. This sets a correct center of transformations, so the group item behaves like regular items. QGraphicsRectItems coordinates have well defined ogirin, it's called pos(), you can change it with setPos() (this also moves item into that point on scene). It shows drawing while moving the mouse which is basically what you want to do - whenever you move one of the nodes, you need to recreate the connection and update it until the moved node is left alone in which case you simply put the last state trigger mouseMoveEvent of several QGraphicsItem at the same time. Hot Network Questions Is it correct to say that primary sources only exist in 'historical times', not in 'pre-history'? General attacking chessboard squares Where exactly does the root directory exist in the linux filesystem? Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; For example, if you move a parent QGraphicsItem, its children will move with it, and if you delete a parent, its children will be deleted. Efficient way to move QGraphicItems I have several QGraphicsItem objects on my custom GraphicsScene. Final Edit. I'm very experienced with Qt's QGraphicsScene, but I'm hoping someone can clarify a detail with regard to the boundingRect and shape methods for a QGraphicsItem. QGraphicsWidget's mouse drag. Modified 7 years, 11 months ago. QGraphicsItem setPos() not triggered. So, the line should be movable but only in y - direction. The situation is illustrated below. I want that the tool tip to follows the mouse as it moves above of the item. To write your own graphics item, you first create a subclass of QGraphicsItem, and then start by implementing its two pure virtual public functions: boundingRect (), which returns an estimate How can I know if a QGraphicsItem created in a separate class has moved on a scene (changed it's position)? item->setFlags(QGraphicsItem::ItemIsSelectable| QGraphicsItem::ItemIsMovable); addItem(item);} else if(event->button() == Qt::RightButton) {// check whether there is an item QGraphicsItem creates an off-screen pixel buffer with a configurable size / resolution that you can pass to setCacheMode(). QGraphicsView scroll problem. Pass mouse events from QGraphicsItem to QGraphicsScene. children, all children are also moved. Suppose, that I've found mouseclick coordinates correctly. That worked fine, but now I have a Note: one of the biggest limitations of QUiLoader is that it cannot "install" an UI on an existing widget (PyQt allows that instead, through uic. QGraphicsItem creates an off-screen pixel buffer with a configurable size / resolution that you can pass to setCacheMode(). pos() coordinates, and since those values are always positive, you are "focusing" on a rectangle that is apparently translated in the opposite direction. In application there are different modes in one of mode user can scroll the scene (palm drag mode). Some of the GraphicsImageItem should move with the parent when clicked, some of them should stay at the same spot when clicked, until the box gets a focusOut by Child QGraphicsItem move event (ItemIsMovable) to its parent. Let's say that you make an application that will be displayed the elements of the network infrastructure on the graphic scene . This seems more intuitive to me. w->setFlag(QGraphicsItem::ItemIsSelectable, true); In addition, as you're adding a widget to the scene, the widget is embedded in a QGraphicsProxyWidget. How to shift the pixels of part of a QGraphicsItem? Hot Network Questions Would reflected sunlight suffice to read a book on the surface of the Moon? QGraphicsItem: how to move it automatically with when QGraphicsScene resizes? Ask Question Asked 7 years, 9 months ago. The general idea Only move QGraphicsItem when mouse in specific region. how to use mouse move event for QGraphicsScene? 1. However, one can manually set the limits of the scene to something bigger than the actual scene. I figured out the issue and posted a solution as an answer below. So if you want to move on the right button I think you'll have to override mouseMoveEvent and do the leg work yourself. Now the half-circle moves around freely but I want it to move just around the fixed central point. Move QGraphicsView top left to a certain point in QGraphicsScene manually. The initial snippet (which I don't have anymore) allowed to move and also select a QgraphicsItem. They have different custom types, so some of them have to handle MouseMove event in one way, and other in different way. Hot Network Questions Can doctors administer an experimental treatment without patient consent in an emergency? Is it normal to connect the positive to a fuse and the negative to the chassis Why doesn't a metal disk expand in all directions when heated? Warning: The suggested solutions won't work for multiply selected items. Allow QGraphicsView to move outside scene. What I did up to now was reimplementing mousePressEvent, mouseReleaseEvent and mouseMoveEvent and called the implementations of QGraphicsItem for these events. In QGraphicsScene::mousemoveEvent, I call mouseMoveEvent of the ruler widget explicitly. The image is rectangular in shape. I'd like to use QGraphicsItemGroup because in this way each disk can access the position of the other. For advanced transformation control you also have the option of Why could a custom QGraphicsItem cause the scene or view to move unless boundingRect is empty? 3. ) is fired, and Qt/C++ - Lesson 023. Viewed 781 times 2 I'm trying to create something similar to terragens node network view in python using PySide. Drag and move graphic polygon work with right mouse button, left create new item. Similar to what you tried in your question, but instead of QGraphicsItem::itemChange(), have a look at QGraphicsItem::mousePressEvent(), QGraphicsItem::mouseMoveEvent(), QGraphicsItem::mouseReleaseEvent() Especially for QGraphicsItem::mouseMoveEvent(): "If While the mouse moves, draw a new QGraphicsItem at the mouse position. This includes defining the item’s geometry, collision detection, its painting implementation and item interaction through its event handlers. cpp I am attempting to properly constrain the movement of a QGraphicsItem (specifically QGraphicsRectItem) without changing the native behavior to function as a scrollbar on the X-axis. You can keep item->setFlags(QGraphicsItem::ItemIsSelectable| QGraphicsItem::ItemIsMovable); addItem(item);} else if(event->button() == Qt::RightButton) {// check whether there is an item Ah, I see. Viewed 126 times 0 . Dear All, I have re-implemented mouseMoveEvent(QGraphicsSceneMouseEvent *event) in my class which is derived from QGraphicsItem. Is there a way to restrict the area where a QGraphicsItem like QRect can be moved when setFlag(ItemIsMovable) is set? I'm new to pyqt and trying to find a way to move an item with the mouse, and the Only move QGraphicsItem when mouse in specific region. Cannot implement Drag and Drop for TextItem. Ask Question Asked 1 year, 7 months ago. dialogcalls a function from the mysquareclass named movePlayer which should move the then move all items by -minX, -minY, then after grouping, move group by minX, minY. All we need to do is to inherit from QGraphicsItem and override the pure virtual boundingRect() function. Make QGraphicsItem movable by right mouse button instead of left. I create them on the fly in focusInEvent() and destroy them in focusOutEvent(). For example, if you drag moving your mouse on your right, it's like moving a camera on the Move QGraphicsItem with mouse hover. So, you can easily access sibling items like this: Hi all, I didn't find a solution for my problem up to now: I have a derived class from QGraphicsProxyWidgets and want to move these in a QGraphicsScene. I created a ruler on top of QGraphicsView and have the ruler tracking mouse movement. loadUi). Handling Mouse Move Events and Context Menu for Square Class Based QGraphicsItem. So? I must double click to item for select it. The default Z value is zero. Adding a QWidget to a QGraphicsScene. Everything is described in the documentation and examples, but each example chooses a different place for the actions. Even when I set the scene (much) larger than the view, view->translate() does not move the contents of the view. When I select some of them and then move selected items only the item that is under the mouse cursor receive MouseMove event but other items does not. wrote on last I am trying to have a half-circle object that is a QGraphicsItem. Someone uses the view, some scene and the other does most of the things in line. MainWindow is most simply, only load custom scene. ItemChange should be called every time a node is moved. the user pressed the mouse on the button with the intent of clicking it and 2. Moving QGraphicsItem on QGraphicsScene with mouse help. I'm trying to make a QGraphicsItem where I can change the size of the object, but I have some problems I cannot solve my self. But the problem is when user try to scroll over scene by dragging (MousePress and MouseMove) on Move the mouse to the right; Release the mouse; This will allow me to check that the item was selected, was moved by the correct amount, and was deselected. __init__() self. This code is pretty interesting. Position of a QGraphicsItem in scene always NULL. QGraphicsItem move object only through X axis. Ask Question Asked 13 years, 11 months ago. We used the QGraphicsItem's mouse moved signal and if it was a left click and drag would use that to query the items drawn on the map, and if it was a middle mouse click and drag we would take the event and change the button and pass that on to QGraphicsItem::mouseMoveEvent so the runtime You have to explicitly set the sceneRect of the QGraphicsScene. Extend graphics item movement around other items without overlap. It will only trigger when i click on the item and move the mouse inside the item (i. If the item is not set as selectable, it will also not be able to be moved. I'm creating a QGraphicsView-derived widget which, amongst other things, needs to create connections between items in it - a little like a control flow graph. I've implemented paint, and that's working. QML animation - moving the application window. If the item has. Your approach doesn't work because you are constantly "translating" the origin point of the sceneRect with the event. I would need to clear the scene, redraw everything, and draw the new position on top. Then emit your own signal for the end-of-move-with-position. A question I meet when adding animation on QGraphicsItem. Simplify your QGraphicsItem::shape() After a careful read of the documentation, my conclusion is that it is not possible to move outside the scene. Rendering quality will typically degrade, depending on the resolution In your itemChange () method, are you sure you are reacting to the correct GraphicsItemChange value? And in the example for the QGraphicsItem::itemChange () void oneBoxHandle::mouseMoveEvent(QGraphicsSceneMouseEvent *event) { QGraphicsItem::mouseMoveEvent(event); setPos(0, y()); if(y() < 0) setPos(x(),0); if(y() > rectY) QGraphicsItem creates an off-screen pixel buffer with a configurable size / resolution that you can pass to setCacheMode(). This article demonstrates how to implement drag and drop of a QGraphicsRectItem at a specific position. move QGraphicsItem continuously in QGraphicsScene and check Collision. The orange item on the left can be dragged onto the gray items. Dragging a QGraphicsSvgItem in Qt. itemChanged never called on QGraphicsItem. QGraphicsRectItem::rect is not updated after item is moved. Most often you will My goal is to write a software that displays two movable disks that live inside the same QGraphicsItemGroup. SGaist Lifetime Qt Champion. Extreme care should be taken when creating QMainWindow and QDialog: if you use QUiLoader, you should not create a main window or dialog in Designer, as you would be actually reparenting them to the widget myObject->setFlag(QGraphicsItem::ItemIsMovable); myObject->setFlag(QGraphicsItem::ItemIsSelectable); myObject->setFlag(QGraphicsItem::ItemSendsGeometryChanges); The only time when the objects move into an incorrect position is when an object I've moved is deleted and removed from the scene, Hi, II'm trying to move a GraphicsItem on a GraphicsScene using moveBy()Function but nothing moves on the screen , may someone help me to achieve this ? Thanks in advance here is the Programmcode i tried to write : ----- class Container: public QGraphicsRectItem { public: Container(QGraphicsItem* parent=0, intx, int y); In my case I cannot call setLine as I am subclassing QGraphicsItem instead of QGraphicsLineItem. Is it possible to animate a QGraphicsItem in such a way that it would move along some path within QGraphicsScene / QGraphicsView? Something like this demo , where white point moves along gear - a closed curve. Why? EDIT: When this happens unselect and mouseRelease point, add a node (QGraphicsItem) – select it and give it mousePress state (plus unset the boolean flag) the user can move node after that, then release mouse. 4. Otherwise, it will grow automatically. I got a solution just now: I use the scrollBars. Moveable QGraphicsItem parent but not child QGraphicsItem. I've seen other questions similar to this say I need to enable mouse tracking, but setMouseTracking is in QWidget, and QGraphicsItem does not appear to be a QWidget. The overlay scene is exactly the same size as the user's Read documentation of QGraphicsItem::ItemPositionChange. QGraphicsItem disappears when dragging the view. Rendering quality will typically degrade, depending on the resolution QGraphicsItem creates an off-screen pixel buffer with a configurable size / resolution that you can pass to setCacheMode(). It is a data flow diagram. Otherwise, use the option QGraphicsItemGroup::setHandlesChildEvents(false) to enable QGraphicsItemGroup items to handle their own events. 2. Viewed 677 times 1 . QGraphicsView behaving differently when mouse is held over a QGraphicsProxyWidget. Moreover, they can only be parented to another QGraphicsItem (apart from being owned by QGraphicsScene. Hot Network Questions Is it possible to manipulate or transform the input within an environment? Advice on dropping out of master's program Luke 20:38 | "God" or "a god" Can I plug a 3 plug extension cord into a 6 plug extender that is plugged into a wall outlet In my case, I had two modes in my tool (measurement and move/rotate) where the scene was basically static and all edit operations were executed by QGraphicsView instead. QGraphicsGridLayout without effect : all components are at the same place. [1/2] Context Hello ! Qt gives us the mean to create highly customized graphics items. How can I enforce QGraphicsItem move as if the user held down the left mouse button and started dragging the item? Namely, the user will press the "add" button, after which the item should appear on the scene immediately in a moving state. I found this example by @serge_gubenko in SO. The example below demonstrates the issue. I have a situation where I need to calculate a shape for many complex paths with the shape including a slight buffer Detailed Description. Move QGraphicsView top left to The mousePressEvent does not work on QGraphicsItems in a QGraphicsItemGroup or in a QList<QGraphicsItem *>. I need to add a QGraphicsItem to the scene and keep it at the same position even when I scroll the view. Qt QGraphicsScene click, select, move, resize, delete QGraphicsItems - QGraphicsSceneTest. QVariant Component::itemChange(GraphicsItemChange change, How to move a QGraphicsItem when scrolling the QGraphicsView? 3. How can a child QGraphicsItem move its parent item ? I set the child item's ItemIsMovable flag and when I try to move the child item, the parent item does not move, only child item moves QGraphicsItem supports projective transformations in addition to its base position, pos(). will move together with the mouse cursor. Handle the ItemPositionChange case to fixate one of your axises. This is done with calls to QGraphicsView::scale. Qt: having selected items appear on top in QGraphicsScene. Same goes The QGraphicsItem already has the behavior of moving to a new position, but when you overwrite these behaviors since you are deleting the implementation of the parent class, if you want to keep the behavior you must call the method of the parent class through super . The QString is then converted to an array of int. QGraphicsTextItem. Something you could do is the following: Subclass QGraphicsScene and implement the mouseMoveEvent; In the mouse move event check if there is an item at the event position using the itemAt function; If there is an item and it is selected (isSelected), get all selected items of the scene. In mouseMoveEvent, you need to identify that particular item and manually restrict the movable area of Dave, thanks a lot. The setSelected is called in QGraphicsItem::mousePressEvent, so you need to propagate it to the base class calling QGraphicsLineItem::mousePressEvent(event) in your overriden mousePressEvent. Then I would look into mouse events for the graphics item. It would be best if I could use the QGraphicsView / QGraphicsScene / QGraphicsItem methods to move item or get the context menu I have not figured out how. Modified 11 years, 11 months ago. To make the objects movable, I use the flag ItemIsMovable which unfortunately doesn't seem to work inside a QGraphicsItemGroup The following I called setPos for each QGraphicsItem during the move. class MainWindow(QMainWindow,myProgram. BboxItem related source code:. My Item implements the hoverMoveEvent() method that fires up a QToolTip. Move an item in a scene Qt. And there is an additional problem: view->translate() causes QGraphicsRectItem::paint() to be called even when the whole rectangle is visible. You can call setPos() only for the last position, when the move is done. Changing QGraphicsItems position within the scene event handler? 0. e. i'm trying to understand if there is a way to move the position of an object inside a QGraphicsItemGroup. Scrolling in QGraphicsView. UI is make in graphic editor. Moving a QGraphicsItem around a central point in PyQt4. move and leave events; inputMethodEvent() handles input events, for accessibility support; keyPressEvent() and keyReleaseEvent() handle key press and release events; Unfortunately it appears that the code in QGraphicsItem::mouseMoveEvent is hard wired to move only on the left button -- regardless of the parameters passed to setAcceptedMouseButtons. Then, you need to subclass QGraphicsTextItem, or create your own QGraphicsItem from scratch. There are several ways to change an item's transformation. Somehow use the animation framework and whenever the mouse moves, animate the QGraphicsItem to move to the new mouse position in 1 millisecond. For example, if you move items from point A to B, call setPos() for point B only and not for each points between A and B. How to place widget correctly in QGraphicsScene. As the documentation states: -. To start viewing messages, select the forum that you want to visit from the selection below. Related. You can keep QGraphicsItem's default move implementation, and still only allow moving along one axis. You can access a QGraphicsItem's parent using QGraphicsItem::parentItem(), and children using QGraphicsItem::childItems(). To set the item's line, pass a QLineF to QGraphicsLineItem's constructor, or call the setLine() function. The position of graphic item is always displayed as 0,0. Qt mouseMoveEvent not firing when mouse pressed. Modified 13 years, 11 months ago. PyQt/PySide How to access/move QGraphicsItem after having added it to QGraphicsScene. Rendering quality will typically degrade, depending on the resolution There's a better way. I expected to see something like. Actually, the Qt Documentation on QGraphicsItem provides an example which exactly solves the problem of limiting the movement of items to the scene rect:. How to move a QGraphicsItem when scrolling the QGraphicsView? 1. An item with a higher Z value will always be drawn on top of another item with a lower Z value. I did then some modifications to end up with: Why is my QGraphicsItem not selectable? If I run the example (Moving a QGraphicsItem around a central point in PyQt4) and click on the graphics item, it automatically shows up with a dashed frame which indicates that The PySide. Currently I'm able to select, drag and scale rectangles using handles. Viewed 2k times 1 . I'm implementing event handlers in a subclass of QGraphicsItem. By default the line is black with a width of 0, but you can change this by calling setPen(). My goal is to get that text after a click on the rectangle. Qt mousemoveevent + Qt::LeftButton. In the case of a large number of items, the worst way to handle this is to create a separate QGraphicsItem / QGraphicsObject for each item and try to move and draw them all independently. I would like to add text to this custom rectangle using its local coordinates (i. functions: boundingRect(), which returns an estimate of the area painted. By doing that, I was able to increase the frame rate in 30%, unfortunately ViewportAnchor::AnchorUnderMouse stopped working. To achieve scrolling over scene I set dragMode of QGraphicsView to ScrollHandDrag. QGraphicsItem leaves artifacts when changing boundingRect. The check itself, you can do it with this QGraphicsItem method:. Changing QGraphicsItems position within the scene event handler? 1. Modified 7 years, 9 months ago. You would need to implement the resizing yourself. Rendering quality will typically degrade, depending on the resolution of the cache and the item transformation. дописать в методы мышки вызов методов базового класса QGraphicsItem::mousePress(Move There's a better way. for example, i want to create a GraphItemGroup and assign some coordinates on the scene. Here is my code: I have multiple QGraphicsItems in scene spread across different parts of scene. @setPos(mapToParent(0,ypos));@ to move something downwards, with ypos incremented in 'advance' member function in QGraphicsItem. But if I have to implement mouse actions, it would be best if I could iterate through he items found at mouse position, instead of all the items in my list (which is likely to be larger). Hot Network Questions Movie where everything turns out You can use QGraphicsItem::setZValue ( qreal z ) to set the Z-value of the item. mapToScene maps items coordinates into scene coordinates, for example mapToScene(QPointF(0,0)) returns scene coordinates of item's upper left corner, mapToScene(QPointF(w,h)) - scene coordinates of Unfortunately, QGraphicsItem is a base class of all graphics items usable inside QGraphicsScene, and, as most "item-like" objects in Qt, is not derived from QWidget or QObject. Modified 8 I have one QGraphicsScene as the main scene with several movable QGraphicsItems in it and another QGraphicsScene on top of the main scene as an overlay. By emitting signals whith mause click events I was able to implement button like features. QtGui. I would like to implement rotation of selected items. Maybe if you override virtual QRectF boundingRect const, you could call the base boundingRect, do a check if it's How to move a QGraphicsItem to another scene without losing the mouse grab? 3. – Nyaruko. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Visit the blog In code below BboxItem represents container QGraphicsItem and BboxItemContent represents childs of it. Hot Network Questions How to move a QGraphicsItem to another scene without losing the mouse grab? Ask Question Asked 14 years, 2 months ago. QGraphicsLineItem uses the line and the pen width to provide a reasonable implementation of boundingRect(), shape(), and QGraphicsItem move object only through X axis. I have created a child of QGraphicsView and have started to overload its mousePressEvent, but it seems that the selection and move actions are QGraphicsItem supports projective transformations in addition to its base position, pos(). Ask Question Asked 8 years ago. This notification is sent if the ItemSendsGeometryChanges flag is enabled, and when the item's local position changes, relative to its I am kicking off with PySide6 and struggling to get my first GraphicsView/Scene and Items working. QGraphicsRectItem move with mouse. He seems to be using the QGraphicsItem::itemChange virtual function to call the tracknodes() function which draws the lines. Ask Question Asked 11 years, 11 months ago. Move QGraphicsItem with mouse hover. QT Graphic scene/view - moving around with mouse. You could compare that against original position to see if moved, or set a flag for "moved" when get itemPositionHasChanged signal. The suggested solution is to override the void paintEvent(QPaintEvent*) of the sub-classed QGraphicsView. How to? 2. S Offline. How to move a QGraphicsItem when scrolling the QGraphicsView? 4. e) how best to move line. Text item that you can add to a QGraphicsScene to display formatted text. 5. Under certain circumstances (defined by a flag values ) I want that the cursor changes its shape (Qt::SizeVerCursor, Qt::SizeHorCursor, Qt::SizeBDiagCursor, Qt::SizeFDiagCursor and Qt::ArrowCursor) when being moved (without any mouse button being pressed) to certain QGraphicsItem move event - get absolute position. The Z value decides the stacking order of sibling items. QGraphicsItem and hover event. The scrollbar method did not have this problem (it internally moves the pixels with memmove(), which is QGraphicsItem creates an off-screen pixel buffer with a configurable size / resolution that you can pass to setCacheMode(). I am having problems with object rotation about the object center after using the predefined move option in Qt. h> class MyBox: public QGraphicsItem I have a GraphicsBoxItem that holds a list of GraphicsImageItem (some kind of floating buttons around the box). I tried overriding the mouseMoveEvent function, but then I need to re-write the behavior for the rectangle in both the X and Y directions. You can schedule changes to the item's transformation matrix at specified steps. py. I would like to have an info label where the current x and y coordinate of the currently moved selection (can consist of many items) is I am trying to use the QGraphicsItemGroup class to constrain a group of objects to move by the same amount in one (e. QGraphicsScene. Mor I want to use QPropertyAnimation on QGraphicsItem, hoping the rect item can move from point(100, 30) to point(100, 90). Hot Network Questions When re-implementing software, does analyzing the original software's kernel-calls make the re-implementation a derived work? How to understand structure of sentences in probability Do you know something is true if and only if you can prove that it is The square now has width and height of 100, but its position is the same and we can can move the square separately from its defined bounding rect. Situation: An upper class dialog generates a raster with squares. PyQt A problem of wait() in QThread using moveToThread() method. I need to resize the png image every time it is dragged by a mouse move event on any side of I am making an app that has a graphic scene where you can drag items in and move them in the scene. . To do that you need to subclass QGraphicsRectItem and implement mouse event handlers: mousePressEvent, mouseMoveEvent, mouseReleaseEvent. Hi, I'm trying to create a movable QGraphicsItem, but I want it to be movable only inside the boundings of another QGraphicsRectItem, I want it so that it stops at the edge when I try to move my item outside of the RectItem, similar to how mouse cursor stops at the end of the screen. f) how to delete a line. When i draw an item on scene and move the mouse cursor inside the item, mouseMoveEvent() will not trigger. Qt: restrict movable area of a QGraphicsItem inside an other QGraphicsItem C++. The HandleItems are children to a ManipulatorItem which in turn scales a DiagramItem of choice. It provides a light-weight foundation for writing your own custom items. Mouse press, move, release and double click events, as well as mouse hover events, wheel events, and context menu events. So you have to restore both files and the second file I will assume is called main_ui. 1. 0. setupUi(self) self. When the mouse is dragging, I change the scrollbars depending on the QMouseEvent x and y. bool QGraphicsItem::collidesWithItem(const QGraphicsItem * other, Qt::ItemSelectionMode mode = Qt::IntersectsItemShape) const Inside the scene I have some QGraphicsItems which the user can select and move. Qt - drag move qgraphicitem don't work nice. In your item, reimplement the itemChange() virtual function. My simple code base on Qt standard example 'diagram scene'. This however only works if I do one of two things: Maybe you can check on QGraphicsItem move event if it is still inside QGraphicsPathItem. You should not modify the code generated by Qt Designer, for more information read QtDesigner changes will be lost after redesign User Interface. It's called in other cases as well but he only uses How to move a QGraphicsItem when scrolling the QGraphicsView? 1. The QGraphicsItemAnimation class has a current step value. The line() function returns the current line. 6. Most often you will The user can move around the scene à la google maps, ie by zooming out then zooming in back a little farther away. Custom QGraphicsRectItem cannot receive mouseMoveEvent. I can also change the scale of the view but my QGraphicsLineItem ignores the scale changes : to achieve that I c) how best to move starting point of a line. Whats the different, when I handle the object in the mouse move event or in the item change event? Best regards, Martin. I've tried two approaches: Creating a QGraphicsLineItem-derived object when the source object's mouseMoveEvent(. Viewed 853 times 1 I am developing an application using pyqt 4 so hopefully I am only making a rookie mistake. If the item is part of a. – The resolution method is to map the point that determines the right, left, up, down to the scene of the first item and the other items obtaining the difference that must be compensated. The problem seems to be that the mouseMove events are seen as hoverMoveEvents by the QGraphicsItem - it should be seen as a mouseMoveEvent! According to the docs: I created a custom qGraphicsRectItem which I added to my qGraphicsScene. In this article, we will discuss how to handle mouse move events and create a context menu for a Square class based on QGraphicsItem in a focused site. For simple transformations, you can call either of the convenience functions setRotation() or setScale(), or you can pass any transformation matrix to setTransform(). The lower part should have another colour than the upper one. My modified version allows movement, but I want to make one QGraphicsItem in a QGraphicsScene move (or change size) when another one moves. Changing QGraphicsItems position within the scene event handler? 7. So you can set it to a higher value to bring it on top : I am implementing undo/redo for move operation on QGraphicsItemGroup in my graphics scene. restrict movable area of PyQt 4 / Qt 4 move QGraphicsItem with mouse using custom event handler. QGraphicsItem customize selection when adding to a group - weird inconsistent results. I tried overriding view's scrollContentsBy() method as follows but it didn't do the trick. As I point out in the other post, you must create classes that inherit from the appropriate widgets. How to prevent child QGraphicsItem from being moved with parent? 1. square->setPos(200, 200); What I want to be able to do is move the entire QGraphicsItem to a set coordinate. void MyGraphicsView::paintEvent(QPaintEvent*) { QPointF scenePos = mapToScene(0,0); // map I have a png image which is displayed on the graphics scene as a QGraphicsPixmapItem. I am trying to prevent collusion between items in the scene and saw this question Prohibit collision of a movable QGraphicsItem with other items which didn't work well for me (perhaps because I am using PyQt6 and translated from qt not very well). [SOLVED] Unable to move QGraphicsItem (delta is always 0) when calculating using If this is your first visit, be sure to check out the FAQ by clicking the link above. Make graphics item move around another item instead of passing through. However, something appears to happen since the scrollbars change. After removing an item from a scene, unless it is parented to another I've a QGraphicsView hows shows a QGraphicsScene which contains a QGraphicsItem. Moving an item with the mouse on QGraphicsView / QGraphicsScene. On the other hand you have to use setAcceptHoverEvents(True) to enable events of the hover type. itemChanged() in QGraphicsItem for a many different items. My command for move looks like: class CommandMove : public QUndoComm No there is no default way to do what you want as far as I know. My original project dealt with Only move QGraphicsItem when mouse in specific region. I can create the object and move it around with the mouse by setting the flag ItemIsMovable. Items should always be visible no matter the zoom value, so they have the QGraphicsItem::ItemIgnoresTransformations flag set. If the ItemIsMoveable flag is set on the parent, dragging the parent will translate the parent and all of it's children. The problem is, only one of the items receives a mouse move event in that case. But, trying to access either QGraphicsItem from the QGraphicsScene object causes crashes. It seems that the QGraphicsWidget moves, without taking the QGraphicsItems along with it. I'm guessing I can do this using collision detection but have move QGraphicsItem continuously in QGraphicsScene and check Collision. adding to 0,0 places the item at the origin of my rectangle no matter where it its in my scene) When I try to do so, it uses my scene's coordinate system and the text appears out of the rectangle. ) Do not move QGraphicsItem after scaling Hello, In my QGraphicsScene I have a QGraphicsItem ( the red rectangle) and a QGraphicsLineItem. In order to request the repainting of your QGraphicsItem, you need to call update() whenever the appearance changes. And I can move the BboxItem by setting its bounding rectangle. 7. Drag move events are generated as the cursor moves around inside the item’s area. Otherwise, drag scene. Here's a dummy example. It says: The item's position changes. I want to improve this by only showing the handles when the item is selected. It works decently for point entity. The QGraphicsItemAnimation class animates a QGraphicsItem. Keyboard input focus, and key events; QGraphicsItem that can be used to render the contents of SVG files. animate a QGraphicsPixmapItem. As far as I can find, the documentation doesn't address this specific concern. I want to tie a few objects (input and output ports) to scene borders, and when @Sridharan So unless there is a "move operation complete" signal (end of drag? drop? but not sure there is one) just recognise "mouse release" event and query pos() then. I've been trying to figure out QGraphics*, and have run into a problem when trying to move an item (a pixmap) relative to or inside of the QGraphicsView. I found I cannot move a QGraphicsItems and QGraphicsItemGroups in a scene once I use custom event For example changing length of a line, move a line, change a polygon by moving one of its points. How to move a QGraphicsItem when scrolling the QGraphicsView? 3. A question about 'itemChange()' of QGraphicsItem. However, this is not dynamic and has limitations. Edit QGraphicsTextItem inside QGraphicsItemGroup. Guess I need to grab the mouse, but it looks dangerous. The purpose is to have the ruler aware of the current mouse position. In my use case, I want to be able to drag the parent and child when dragging from anywhere inside the parent but not also inside the child. #ifndef MYBOX_H #define MYBOX_H #include <QGraphicsItem> #include <boxhandle. Then, I try to move the QGraphicsWidget within the scene by calling setPos(), but it doesn't appear to work (the QGraphicsItems remain in the same place). The dummy code: @yoon, you want to move a widget, let’s say a QPushButton, without having a QGraphicsItem, right? And I say it is possible, but only if you find a way to differentiate between two events: 1. You will want it to be fixed size. I want to be able to move it using the mouse, by clicking and dragging. I'm trying to extend my Qt knowledge to QGraphicsView by implementing a diagram-ish application. scene = QGraphicsScene() I have subclassed QGraphicsRectItem, and it's not receiving any mouse events. I subclassed QGraphicsScene and added the method mouseMoveEvent to handle mouse move events. d) how best to move end point of a line. I had to rummage though the code to figure out what was moving the QGraphicsItem. In my subclassed QGraphicsView I am getting mouse events. If you have stumbled here from google looking for a decent way to move QGraphicsItems / QGraphicsObjects via the ItemIsMovable flag while avoiding collision with other nodes, I included a working itemChange method at the very end of my answer. I have noticed that there are 2 functions - rotate() which performs an immediate action but does not save the rotation on the item - and setRotation(), which stores rotation() (though it requires a repaint causing event). I want to automatically: Resize BlueItem's width when I click and drag RedItem. It forwards events between the two objects and translates between QWidget's integer-based @SGaist Yes thank you, I will keep it in mind. Since the system provides lots of methods and flags, my first assumption was that in order to move a widget I would only need to enable the widget being moved by activating the flag IsMovable. Ui_MainWindow): def __init__(self): super(). The rotations work The user can move the line up and down in order the change the size of the upper and the lower part. How to detect a QGraphicsItem moving performing by mouse? 2. (The node is a child item of the point. See also the code below: This question is related to: Forcing QGraphicsItem To Stay Put I'd like to have a QGraphicsItem on a fixed location when moving around in the scene. But I am having trouble implementing a method to 'draw' the connections . I will be more precise, when you want to move several items together it is normal to use the mouse + rubberband to select those items, and then at that time you can add the items to the group, then move them and before a certain action could be removed the items of the group, that is to say limit the action of the group only when necessary and thus the item will not be move QGraphicsItem continuously in QGraphicsScene and check Collision. setParentItem(parentItem). void FETimelineView::scrollContentsBy( int dx, int dy ) { QGraphicsView::scrollContentsBy(dx, dy); QRectF oRect = p_CatBar->rect(); p_CatBar When creating a QGraphicsItem via QT and Pyside, you can set it's parent using childItem. However, as the rectangle is moved in the scene, the rect returned by boundingRect() always returns the original value for the bounding rectangle. A player sits at (0,0) and when the user clicks on a square a pathfinding algoritm pathFind generates a QString of directions the player has to take to reach this goal. There are several ways to change an item’s transformation. And item need double click with no release last click when I want move item. For all selected That seems like it works but it breaks another workaround we have. bebamnzvmrdegxmgsqmkuxkhmgerzyznkuspiocuitfhvtounsf