wxClientDC(3erl) | Erlang Module Definition | wxClientDC(3erl) |
wxClientDC - Functions for wxClientDC class
wxClientDC is primarily useful for obtaining information about the window from outside EVT_PAINT() handler.
Typical use of this class is to obtain the extent of some text string in order to allocate enough size for a window, e.g.
Note: While wxClientDC may also be used for drawing on the client area of a window from outside an EVT_PAINT() handler in some ports, this does not work on all platforms (neither wxOSX nor wxGTK with GTK 3 Wayland backend support this, so drawing using wxClientDC simply doesn't have any effect there) and the only portable way of drawing is via wxPaintDC. To redraw a small part of the window, use wxWindow:refreshRect/3 to invalidate just this part and check wxWindow:getUpdateRegion/1 in the paint event handler to redraw this part only.
wxClientDC objects should normally be constructed as temporary stack objects, i.e. don't store a wxClientDC object.
A wxClientDC object is initialized to use the same font and colours as the window it is associated with.
See: wxDC, wxMemoryDC, wxPaintDC, wxWindowDC, wxScreenDC
This class is derived (and can use functions) from: wxWindowDC wxDC
wxWidgets docs: wxClientDC
wxClientDC() = wx:wx_object()
new(Window) -> wxClientDC()
Types:
Constructor.
Pass a pointer to the window on which you wish to paint.
destroy(This :: wxClientDC()) -> ok
Destroys the object.
wx 2.2.1 | wxWidgets team. |