NWidgetViewport Class Reference
[Hierarchical widgets]

Nested widget to display a viewport in a window. More...

#include <widget_type.h>

Inheritance diagram for NWidgetViewport:
NWidgetCore NWidgetResizeBase NWidgetBase ZeroedMemoryAllocator

Public Member Functions

 NWidgetViewport (int index)
void SetupSmallestSize (Window *w, bool init_array)
 Compute smallest size needed by the widget.
void Draw (const Window *w)
 Draw the widgets of the tree.
ScrollbarFindScrollbar (Window *w, bool allow_next=true) const
 Find the scrollbar of the widget through the Window::nested_array.
void InitializeViewport (Window *w, uint32 follow_flags, ZoomLevel zoom)
 Initialize the viewport of the window.
void UpdateViewportCoordinates (Window *w)
 Update the position and size of the viewport (after eg a resize).

Detailed Description

Nested widget to display a viewport in a window.

After initializing the nested widget tree, call InitializeViewport(). After changing the window size, call UpdateViewportCoordinates() eg from Window::OnResize(). If the display_flags field contains the ND_NO_TRANSPARENCY bit, the viewport will disable transparency. Shading to grey-scale is controlled with the ND_SHADE_GREY bit (used for B&W news papers), the ND_SHADE_DIMMED gives dimmed colours (for colour news papers).

Todo:
Class derives from NWidgetCore, but does not use colour, widget_data, or tool_tip.

Definition at line 456 of file widget_type.h.


Member Function Documentation

void NWidgetViewport::Draw ( const Window w  )  [virtual]

Draw the widgets of the tree.

The function calls Window::DrawWidget for each widget with a non-negative index, after the widget itself is painted.

Parameters:
w Window that owns the tree.

Implements NWidgetBase.

Definition at line 1637 of file widget.cpp.

References NWidgetBase::current_x, NWidgetBase::current_y, NWidgetCore::disp_flags, Window::DrawViewport(), FILLRECT_RECOLOUR, GfxFillRect(), ND_NO_TRANSPARENCY, ND_SHADE_DIMMED, ND_SHADE_GREY, NWidgetBase::pos_x, and NWidgetBase::pos_y.

Scrollbar * NWidgetViewport::FindScrollbar ( Window w,
bool  allow_next = true 
) const [virtual]

Find the scrollbar of the widget through the Window::nested_array.

Parameters:
w Window containing the widgets and the scrollbar,
allow_next Search may be extended to the next widget.
Todo:
This implementation uses the constraint that a scrollbar must be the next item in the Window::nested_array, and the scrollbar data is stored in the Window structure (Window::vscroll, Window::vscroll2, and Window::hscroll). Alternative light-weight implementations may be considered, eg by sub-classing a canvas-like widget, and/or by having an explicit link between the scrollbar and the widget being scrolled.

Implements NWidgetCore.

Definition at line 1655 of file widget.cpp.

void NWidgetViewport::InitializeViewport ( Window w,
uint32  follow_flags,
ZoomLevel  zoom 
)

Initialize the viewport of the window.

Parameters:
w Window owning the viewport.
follow_flags Type of viewport, see InitializeViewport().
zoom Zoom level.

Definition at line 1666 of file widget.cpp.

References NWidgetBase::current_x, NWidgetBase::current_y, InitializeWindowViewport(), NWidgetBase::pos_x, and NWidgetBase::pos_y.

void NWidgetViewport::SetupSmallestSize ( Window w,
bool  init_array 
) [virtual]

Compute smallest size needed by the widget.

The smallest size of a widget is the smallest size that a widget needs to display itself properly. In addition, filling and resizing of the widget are computed. The function calls Window::UpdateWidgetSize for each leaf widget and background widget without child with a non-negative index.

Parameters:
w Window owning the widget.
init_array Initialize the w->nested_array.
Note:
After the computation, the results can be queried by accessing the smallest_x and smallest_y data members of the widget.

Implements NWidgetBase.

Definition at line 1627 of file widget.cpp.

References NWidgetCore::index, NWidgetResizeBase::min_x, NWidgetResizeBase::min_y, Window::nested_array, Window::nested_array_size, NWidgetBase::smallest_x, and NWidgetBase::smallest_y.

void NWidgetViewport::UpdateViewportCoordinates ( Window w  ) 

The documentation for this class was generated from the following files:

Generated on Sat Nov 20 21:00:08 2010 for OpenTTD by  doxygen 1.6.1