#include <Wt/WLayout>
Public Member Functions | |
virtual | ~WLayout () |
Destroy the layout. | |
virtual void | addItem (WLayoutItem *item)=0 |
Add a layout item. | |
void | addWidget (WWidget *widget) |
Add the given widget to the layout. | |
virtual void | removeItem (WLayoutItem *item)=0 |
Remove a layout item (widget or nested layout). | |
void | removeWidget (WWidget *widget) |
Remove the given widget from the layout. | |
virtual int | count () const =0 |
Return the number of items in this layout. | |
virtual WLayoutItem * | itemAt (int index) const =0 |
Return the layout item at a specific index. | |
virtual int | indexOf (WLayoutItem *item) const |
Return the index of a given item. | |
virtual WWidgetItem * | findWidgetItem (WWidget *widget) |
Finds the widget item associated with the given widget. | |
void | setLayoutHint (const std::string &name, const std::string &value) |
Provide a hint to the layout implementation. | |
virtual WWidget * | widget () |
Get the widget that is held by this WLayoutItem. | |
virtual WLayout * | layout () |
Get the layout that implements this WLayoutItem. | |
WLayoutItemImpl * | impl () const |
Get the implementation for this layout item. | |
void | setContentsMargins (int left, int top, int right, int bottom) |
Set contents margins (in pixels). | |
void | getContentsMargins (int *left, int *top, int *right, int *bottom) const |
Returns the contents margins. | |
Protected Member Functions | |
WLayout () | |
Create a layout. | |
void | update (WLayoutItem *item=0) |
Update the layout. | |
void | updateAddItem (WLayoutItem *item) |
Update the layout, adding the given layout item. | |
void | updateRemoveItem (WLayoutItem *item) |
Update the layout, remove the given layout item. | |
void | setLayoutInParent (WWidget *parent) |
Set the layout in the parent. |
This class is the abstract base class for any layout manager. A layout manager is associated with a container widget, and manages the layout of children inside the whole space available to the container widget.
Layout managers may be used with WContainerWidget and Ext::Container container widgets. A suitable implementation for all layout classes is not yet available for both containers, and thus you need to refer to the documentation of a layout manager to see if it is applicable to your situation.
The implementation of the layout manager depends on the container widget to which it is set, and is therefore deferred to WLayoutImpl.
A layout never assumes ownership of contained items, instead these are owned by the parent widget to which the layout is applied.
virtual void Wt::WLayout::addItem | ( | WLayoutItem * | item | ) | [pure virtual] |
Add a layout item.
The item may be a widget or nested layout.
How the item is layed out with respect to siblings is implementation specific to the layout manager. In some cases, a layout manager will overload this method with extra arguments that specify layout options.
Implemented in Wt::WBorderLayout, Wt::WBoxLayout, Wt::WDefaultLayout, Wt::WFitLayout, and Wt::WGridLayout.
void Wt::WLayout::addWidget | ( | WWidget * | widget | ) |
Add the given widget to the layout.
This method wraps the widget in a WWidgetItem and calls addItem(WLayoutItem *).
How the widget is layed out with respect to siblings is implementation specific to the layout manager. In some cases, a layout manager will overload this method with extra arguments that specify layout options.
virtual void Wt::WLayout::removeItem | ( | WLayoutItem * | item | ) | [pure virtual] |
Remove a layout item (widget or nested layout).
Implemented in Wt::WBorderLayout, Wt::WBoxLayout, Wt::WDefaultLayout, Wt::WFitLayout, and Wt::WGridLayout.
void Wt::WLayout::removeWidget | ( | WWidget * | widget | ) |
Remove the given widget from the layout.
This method finds the corresponding WWidgetItem and calls removeItem(WLayoutItem *). The widget itself is not destroyed.
virtual int Wt::WLayout::count | ( | ) | const [pure virtual] |
Return the number of items in this layout.
This may be a theoretical number, which is greater than the actual number of items. It can be used to iterate over the items in the layout, in conjunction with itemAt().
Implemented in Wt::WBorderLayout, Wt::WBoxLayout, Wt::WDefaultLayout, Wt::WFitLayout, and Wt::WGridLayout.
virtual WLayoutItem* Wt::WLayout::itemAt | ( | int | index | ) | const [pure virtual] |
Return the layout item at a specific index.
If there is no item at the index, 0 is returned.
Implemented in Wt::WBorderLayout, Wt::WBoxLayout, Wt::WDefaultLayout, Wt::WFitLayout, and Wt::WGridLayout.
int Wt::WLayout::indexOf | ( | WLayoutItem * | item | ) | const [virtual] |
Return the index of a given item.
The default implementation loops over all items, and returns the index for which itemAt(index) equals item.
Reimplemented in Wt::WDefaultLayout, and Wt::WFitLayout.
void Wt::WLayout::setLayoutHint | ( | const std::string & | name, | |
const std::string & | value | |||
) |
Provide a hint to the layout implementation.
In some caes, a layout implementation may require some hints for rendering its contents. Possible hints are indicated in the reference documentation for each layout manager.
virtual WWidget* Wt::WLayout::widget | ( | ) | [inline, virtual] |
Get the widget that is held by this WLayoutItem.
This implements a type-safe upcasting mechanism to a WWidgetItem.
Implements Wt::WLayoutItem.
virtual WLayout* Wt::WLayout::layout | ( | ) | [inline, virtual] |
Get the layout that implements this WLayoutItem.
This implements a type-safe upcasting mechanism to a WLayout.
Implements Wt::WLayoutItem.
WLayoutItemImpl* Wt::WLayout::impl | ( | ) | const [inline, virtual] |
Get the implementation for this layout item.
The implementation of a layout item depends on the kind of container for which the layout does layout management.
Implements Wt::WLayoutItem.
void Wt::WLayout::setContentsMargins | ( | int | left, | |
int | top, | |||
int | right, | |||
int | bottom | |||
) |
Set contents margins (in pixels).
The default contents margins are 9 pixels in all directions.
void Wt::WLayout::getContentsMargins | ( | int * | left, | |
int * | top, | |||
int * | right, | |||
int * | bottom | |||
) | const |
void Wt::WLayout::update | ( | WLayoutItem * | item = 0 |
) | [protected] |
Update the layout.
Must be called whenever some properties of the layout have changed.
void Wt::WLayout::updateAddItem | ( | WLayoutItem * | item | ) | [protected] |
Update the layout, adding the given layout item.
Must be called from the implementation of addItem(WLayoutItem *)
void Wt::WLayout::updateRemoveItem | ( | WLayoutItem * | item | ) | [protected] |
Update the layout, remove the given layout item.
Must be called from the implementation of removeItem(WLayoutItem *)
void Wt::WLayout::setLayoutInParent | ( | WWidget * | parent | ) | [protected] |