***************** wx.ScrolledWindow ***************** Inheritance diagram for `wx.ScrolledWindow`: | .. inheritance-diagram:: wx.ScrolledWindow | Description =========== The `wx.ScrolledWindow` class manages scrolling for its client area, transforming the coordinates according to the scrollbar positions, and setting the scroll positions, thumb sizes and ranges according to the area in view. Starting from version 2.4 of wxWidgets, there are several ways to use a `wx.ScrolledWindow`. In particular, there are now three ways to set the size of the scrolling area: * One way is to set the scrollbars directly using a call to `SetScrollbars <#SetScrollbars>`_. This is the way it used to be in any previous version of wxWidgets and it will be kept for backwards compatibility. * An additional method of manual control, which requires a little less computation of your own, is to set the total size of the scrolling area by calling either `wx.Window.SetVirtualSize `_, or `wx.Window.FitInside `_, and setting the scrolling increments for it by calling `SetScrollRate <#SetScrollRate>`_. Scrolling in some orientation is enabled by setting a non-zero increment for it. * The most automatic and newest way is to simply let sizers determine the scrolling area. This is now the default when you set an interior sizer into a `wx.ScrolledWindow` with `wx.Window.SetSizer `_. The scrolling area will be set to the size requested by the sizer and the scrollbars will be assigned for each orientation according to the need for them and the scrolling increment set by `SetScrollRate <#SetScrollRate>`_. As above, scrolling is only enabled in orientations with a non-zero increment. You can influence the minimum size of the scrolled area controlled by a sizer by calling `wx.Window.SetVirtualSizeHints `_. (calling `SetScrollbars <#SetScrollbars>`_ has analogous effects in wxWidgets 2.4 -- in later versions it may not continue to override the sizer) .. note:: If Maximum size hints are still supported by `SetVirtualSizeHints`, use them at your own dire risk. They may or may not have been removed for 2.4, but it really only makes sense to set minimum size hints here. We should probably replace `SetVirtualSizeHints` with `SetMinVirtualSize` or similar and remove it entirely in future. As with all windows, an application can draw onto a `wx.ScrolledWindow` using a device context. You have the option of handling the `OnPaint` handler or overriding the `OnDraw` function, which is passed a pre-scrolled device context (prepared by `DoPrepareDC <#DoPrepareDC>`_). If you don't wish to calculate your own scrolling, you must call `DoPrepareDC` when not drawing from within `OnDraw`, to set the device origin for the device context according to the current scroll position. A `wx.ScrolledWindow` will normally scroll itself and therefore its child windows as well. It might however be desired to scroll a different window than itself: e.g. when designing a spreadsheet, you will normally only have to scroll the (usually white) cell area, whereas the (usually grey) label area will scroll very differently. For this special purpose, you can call `SetTargetWindow <#SetTargetWindow>`_ which means that pressing the scrollbars will scroll a different window. .. note:: Note that the underlying system knows nothing about scrolling coordinates, so that all system functions (mouse events, expose events, refresh calls etc) as well as the position of subwindows are relative to the "physical" origin of the scrolled window. If the user insert a child window at position (10, 10) and scrolls the window down 100 pixels (moving the child window out of the visible area), the child window will report a position of (10, -90). .. seealso:: `wx.ScrollBar `_, `wx.ClientDC `_, `wx.PaintDC `_, `wx.VScrolledWindow `_ Derived From ^^^^^^^^^^^^^ * `wx.Panel `_ * `wx.Window `_ * `wx.EvtHandler `_ * `wx.Object `_ Known Subclasses ^^^^^^^^^^^^^^^^ `wx.PreviewCanvas `_, `wx.PyScrolledWindow `_ Window Styles ^^^^^^^^^^^^^ ================================================== ================================================== Window Style Description ================================================== ================================================== ``wx.RETAINED`` Uses a backing pixmap to speed refreshes. Motif only. ================================================== ================================================== Remarks ^^^^^^^ Use `wx.ScrolledWindow` for applications where the user scrolls by a fixed amount, and where a 'page' can be interpreted to be the current visible portion of the window. For more sophisticated applications, use the `wx.ScrolledWindow` implementation as a guide to build your own scroll behaviour. Methods Summary ^^^^^^^^^^^^^^^ * `__init__ <#__init__>`_ * `AdjustScrollbars <#AdjustScrollbars>`_ * `CalcScrollInc <#CalcScrollInc>`_ * `CalcScrolledPosition <#CalcScrolledPosition>`_ * `CalcUnscrolledPosition <#CalcUnscrolledPosition>`_ * `DoPrepareDC <#DoPrepareDC>`_ * `EnableScrolling <#EnableScrolling>`_ * `GetScaleX <#GetScaleX>`_ * `GetScaleY <#GetScaleY>`_ * `GetScrollPageSize <#GetScrollPageSize>`_ * `GetScrollPixelsPerUnit <#GetScrollPixelsPerUnit>`_ * `GetTargetRect <#GetTargetRect>`_ * `GetTargetWindow <#GetTargetWindow>`_ * `GetViewStart <#GetViewStart>`_ * `GetVirtualSize <#GetVirtualSize>`_ * `Scroll <#Scroll>`_ * `SetScale <#SetScale>`_ * `SetScrollPageSize <#SetScrollPageSize>`_ * `SetScrollRate <#SetScrollRate>`_ * `SetScrollbars <#SetScrollbars>`_ * `SetTargetRect <#SetTargetRect>`_ * `SetTargetWindow <#SetTargetWindow>`_ Properties Summary ^^^^^^^^^^^^^^^^^^ * `ScaleX <#ScaleX>`_ * `ScaleY <#ScaleY>`_ * `TargetWindow <#TargetWindow>`_ * `ViewStart <#ViewStart>`_ Class API ========= Methods ^^^^^^^ .. method:: __init__(parent, id=-1, pos=wx.DefaultPosition, size=wx.DefaultSize, style=wx.HSCROLL|wx.VSCROLL, name=wx.PanelNameStr) Constructor. **Parameters:** * `parent` (`wx.Window `_) * `id` (int) * `pos` (`wx.Point `_) * `size` (`wx.Size `_) * `style` (long) * `name` (string) | **Returns:** `wx.ScrolledWindow `_ .. note:: The window is initially created without visible scrollbars. Call `SetScrollbars <#SetScrollbars>`_ to specify how big the virtual window size should be. -------- .. method:: AdjustScrollbars() `No docstrings available for this method.` -------- .. method:: CalcScrollInc(event) | **Parameters:** * `event` (`wx.ScrollWinEvent <../Events/wx.ScrollWinEvent.html>`_) | **Returns:** `int` -------- .. method:: CalcScrolledPosition(x, y) Translates the logical coordinates to the device ones. For example, if a window is scrolled 10 pixels to the bottom, the device coordinates of the origin are (0, 0) (as always), but the logical coordinates are (0, 10) and so the call to `CalcScrolledPosition(0, 10)` will return 0 in `yy`. **Parameters:** * `x` (int) * `y` (int) | **Returns:** `(xx, yy)` .. seealso:: `CalcUnscrolledPosition <#CalcUnscrolledPosition>`_ -------- .. method:: CalcUnscrolledPosition(x, y) Translates the device coordinates to the logical ones. For example, if a window is scrolled 10 pixels to the bottom, the device coordinates of the origin are (0, 0) (as always), but the logical coordinates are (0, 10) and so the call to `CalcUnscrolledPosition(0, 0)` will return 10 in `yy`. **Parameters:** * `x` (int) * `y` (int) | **Returns:** `(xx, yy)` .. seealso:: `CalcScrolledPosition <#CalcScrolledPosition>`_ -------- .. method:: DoPrepareDC(dc) Call this function to prepare the device context for drawing a scrolled image. It sets the device origin according to the current scroll position. `DoPrepareDC` is called automatically within the default `OnPaint` event handler, so your `OnDraw` override will be passed a 'pre-scrolled' device context. However, if you wish to draw from outside of `OnDraw` (via `OnPaint`), or you wish to implement `OnPaint` yourself, you must call this function yourself. For example:: def OnEvent(self, event): dc = wx.ClientDC(self) self.DoPrepareDC(dc) dc.SetPen(wx.BLACK_PEN) xpos, ypos = event.GetPosition() if (xpos > -1 and ypos > -1 and event.Dragging()): dc.DrawLine(xpos, ypos, x, y) **Parameters:** * `dc` (`wx.DC `_) -------- .. method:: EnableScrolling(x_scrolling, y_scrolling) Enable or disable physical scrolling in the given direction. Physical scrolling is the physical transfer of bits up or down the screen when a scroll event occurs. If the application scrolls by a variable amount (e.g. if there are different font sizes) then physical scrolling will not work, and you should switch it off. **Parameters:** * `x_scrolling` (bool) * `y_scrolling` (bool) .. note:: Physical scrolling may not be available on all platforms. Where it is available, it is enabled by default. .. note:: Note that you will have to reposition child windows yourself, if physical scrolling is disabled. -------- .. method:: GetScaleX() `No docstrings available for this method.` -------- .. method:: GetScaleY() `No docstrings available for this method.` -------- .. method:: GetScrollPageSize(orient) | **Parameters:** * `orient` (int) | **Returns:** `int` -------- .. method:: GetScrollPixelsPerUnit() Get the number of pixels per scroll unit (line), in each direction, as set by `SetScrollbars <#SetScrollbars>`_. A value of zero indicates no scrolling in that direction. | **Returns:** `(xUnit, yUnit)` .. seealso:: `SetScrollbars <#SetScrollbars>`_, `GetVirtualSize <#GetVirtualSize>`_ -------- .. method:: GetTargetRect() `No docstrings available for this method.` -------- .. method:: GetTargetWindow() `No docstrings available for this method.` -------- .. method:: GetViewStart() Get the position at which the visible portion of the window starts. | **Returns:** `(xView, yView)` .. note:: If either of the scrollbars is not at the home position, `xView` and/or `yView` will be greater than zero. Combined with `wx.Window.GetClientSize `_, the application can use this function to efficiently redraw only the visible portion of the window. The positions are in logical scroll units, not pixels, so to convert to pixels you will have to multiply by the number of pixels per scroll increment. .. seealso:: `SetScrollbars <#SetScrollbars>`_ -------- .. method:: GetVirtualSize() Gets the size in device units of the scrollable window area (as opposed to the client size, which is the area of the window currently visible). .. note:: Use `wx.DC.DeviceToLogicalX `_ and `wx.DC.DeviceToLogicalY `_ to translate these units to logical units. .. seealso:: `SetScrollbars <#SetScrollbars>`_, `GetScrollPixelsPerUnit <#GetScrollPixelsPerUnit>`_ -------- .. method:: Scroll(x, y) Scrolls a window so the view start is at the given point. **Parameters:** * `x` (int) * `y` (int) .. note:: The positions are in scroll units, not pixels, so to convert to pixels you will have to multiply by the number of pixels per scroll increment. If either parameter is -1, that position will be ignored (no change in that direction). .. seealso:: `SetScrollbars <#SetScrollbars>`_, `GetScrollPixelsPerUnit <#GetScrollPixelsPerUnit>`_ -------- .. method:: SetScale(xs, ys) | **Parameters:** * `xs` (double) * `ys` (double) -------- .. method:: SetScrollPageSize(orient, pageSize) | **Parameters:** * `orient` (int) * `pageSize` (int) -------- .. method:: SetScrollRate(xstep, ystep) Set the horizontal and vertical scrolling increment only. See the `pixelsPerUnit` parameter in `SetScrollbars`. **Parameters:** * `xstep` (int) * `ystep` (int) -------- .. method:: SetScrollbars(pixelsPerUnitX, pixelsPerUnitY, noUnitsX, noUnitsY, xPos=0, yPos=0, noRefresh=False) Sets up vertical and/or horizontal scrollbars. **Parameters:** * `pixelsPerUnitX` (int): Pixels per scroll unit in the horizontal direction. * `pixelsPerUnitY` (int): Pixels per scroll unit in the vertical direction. * `noUnitsX` (int): Number of units in the horizontal direction. * `noUnitsY` (int): Number of units in the vertical direction. * `xPos` (int): Position to initialize the scrollbars in the horizontal direction, in scroll units. * `yPos` (int): Position to initialize the scrollbars in the vertical direction, in scroll units. * `noRefresh` (bool): Will not refresh window if ``True``. | The first pair of parameters give the number of pixels per 'scroll step', i.e. amount moved when the up or down scroll arrows are pressed. The second pair gives the length of scrollbar in scroll steps, which sets the size of the window. `xPos` and `yPos` optionally specify a position to scroll to immediately. For example, the following gives a window horizontal and vertical scrollbars with 20 pixels per scroll step, and a size of 50 steps (1000 pixels) in each direction:: window.SetScrollbars(20, 20, 50, 50) `wx.ScrolledWindow` manages the page size itself, using the current client window size as the page size. .. note:: Note that for more sophisticated scrolling applications, for example where scroll steps may be variable according to the position in the document, it will be necessary to derive a new class from `wx.Window `_, overriding `OnSize` and adjusting the scrollbars appropriately. .. seealso:: `wx.Window.SetVirtualSize `_ -------- .. method:: SetTargetRect(rect) | **Parameters:** * `rect` (`wx.Rect `_) -------- .. method:: SetTargetWindow(window) Call this function to tell `wx.ScrolledWindow` to perform the actual scrolling on a different window (and not on itself). **Parameters:** * `window` (`wx.Window `_) -------- Properties ^^^^^^^^^^ .. attribute:: ScaleX See `GetScaleX <#GetScaleX>`_ .. attribute:: ScaleY See `GetScaleY <#GetScaleY>`_ .. attribute:: TargetWindow See `GetTargetWindow <#GetTargetWindow>`_ and `SetTargetWindow <#SetTargetWindow>`_ .. attribute:: ViewStart See `GetViewStart <#GetViewStart>`_