The BGroupLayout class is a simple BLayout subclass that arranges the items it holds within a vertical or horizontal box. More...
Inherits BTwoDimensionalLayout.
Public Member Functions | |
BGroupLayout (BMessage *from) | |
Archive constructor. | |
BGroupLayout (orientation orientation, float spacing=B_USE_DEFAULT_SPACING) | |
Creates a new BGroupLayout. | |
virtual | ~BGroupLayout () |
Destructor method. | |
virtual bool | AddItem (BLayoutItem *item) |
Adds item to this layout as the last item. In a vertical BGroupLayout, item will be on the right, in a horizontal BGroupLayout, item will be at the bottom. | |
virtual bool | AddItem (BLayoutItem *item, float weight) |
Adds item to the end of this layout with a weight of weight. | |
virtual bool | AddItem (int32 index, BLayoutItem *item) |
Adds item to this layout at index. | |
virtual bool | AddItem (int32 index, BLayoutItem *item, float weight) |
Adds item this layout at index with a weight of weight. | |
virtual BLayoutItem * | AddView (BView *child) |
Adds child to this layout as the last item. In a vertical BGroupLayout, child will be on the right, in a horizontal BGroupLayout, child will be at the bottom. | |
virtual BLayoutItem * | AddView (BView *child, float weight) |
Adds child to the end of this layout with a weight of weight. | |
virtual BLayoutItem * | AddView (int32 index, BView *child) |
Adds child to this layout at index. | |
virtual BLayoutItem * | AddView (int32 index, BView *child, float weight) |
Adds child this layout at index with a weight of weight. | |
virtual status_t | Archive (BMessage *into, bool deep=true) const |
Archives this layout into archive. If deep is true, also archives the items in this layout, calling ItemArchived() for each one. | |
float | ItemWeight (int32 index) const |
Get the weight of the item at index. | |
orientation | Orientation () const |
Get the orientation of this BGroupLayout. | |
virtual status_t | Perform (perform_code d, void *arg) |
Perform some action (Internal method defined for binary compatibility purposes). | |
void | SetItemWeight (int32 index, float weight) |
Set the weight of the item at index. | |
void | SetOrientation (orientation orientation) |
Set the orientation of this BGroupLayout. | |
void | SetSpacing (float spacing) |
Set the amount of spacing (in pixels) between each item. | |
float | Spacing () const |
Get the amount of spacing (in pixels) between each item. | |
Public Member Functions inherited from BTwoDimensionalLayout | |
BTwoDimensionalLayout () | |
Create an empty layout. | |
BTwoDimensionalLayout (BMessage *from) | |
Unarchive constructor. | |
virtual | ~BTwoDimensionalLayout () |
Destructor. | |
void | AlignLayoutWith (BTwoDimensionalLayout *other, orientation orientation) |
Align the BLayoutItem's in the specified orientation within two or more BTwoDimensionalLayout's. | |
virtual status_t | Archive (BMessage *into, bool deep=true) const |
Archives this layout into archive. If deep is true, also archives the items in this layout, calling ItemArchived() for each one. | |
virtual BAlignment | BaseAlignment () |
Method to be implemented in derived classes return the preferred alignment for this BAbstractLayout. | |
virtual BSize | BaseMaxSize () |
Method to be implemented in derived classes return the maximum size constraint for this BAbstractLayout. | |
virtual BSize | BaseMinSize () |
Method to be implemented in derived classes return the minimum size constraint for this BAbstractLayout. | |
virtual BSize | BasePreferredSize () |
Method to be implemented in derived classes return the preferred size constraint for this BAbstractLayout. | |
virtual void | GetHeightForWidth (float width, float *min, float *max, float *preferred) |
Get this BLayoutItem's height constraints for a given width. | |
void | GetInsets (float *left, float *top, float *right, float *bottom) const |
Get the insets for the BTwoDimensionalLayout (in pixels). | |
virtual bool | HasHeightForWidth () |
Returns whether or not this BLayoutItem's height constraints are dependent on its width. | |
virtual status_t | Perform (perform_code d, void *arg) |
Perform some action (Internal method defined for binary compatibility purposes). | |
virtual void | SetFrame (BRect frame) |
Set the bounding frame of this item. | |
void | SetInsets (float horizontal, float vertical) |
Set the insets for this layout. | |
void | SetInsets (float insets) |
Set the insets for this layout. | |
void | SetInsets (float left, float top, float right, float bottom) |
Set the insets for this layout. | |
Public Member Functions inherited from BAbstractLayout | |
virtual BAlignment | Alignment () |
virtual status_t | Archive (BMessage *into, bool deep=true) const |
Archives this layout into archive. If deep is true, also archives the items in this layout, calling ItemArchived() for each one. | |
virtual BRect | Frame () |
Return the bounding frame of this item. | |
virtual bool | IsVisible () |
Return the current local visibility of this item. If an item is not visible, it will not be given space by the BLayout it resides in. | |
virtual BSize | MaxSize () |
virtual BSize | MinSize () |
virtual status_t | Perform (perform_code d, void *arg) |
Perform some action (Internal method defined for binary compatibility purposes). | |
virtual BSize | PreferredSize () |
virtual void | SetExplicitAlignment (BAlignment alignment) |
Set this item's explicit alignment, to be used in Alignment(). | |
virtual void | SetExplicitMaxSize (BSize size) |
Set this item's explicit max size, to be used in MaxSize(). | |
virtual void | SetExplicitMinSize (BSize size) |
Set this item's explicit min size, to be used in MinSize(). | |
virtual void | SetExplicitPreferredSize (BSize size) |
Set this item's explicit preferred size, to be used in PreferredSize(). | |
virtual void | SetFrame (BRect frame) |
Set the bounding frame of this item. | |
virtual void | SetVisible (bool visible) |
Set the local visibility of this item. | |
BAbstractLayout () | |
Construct a BAbstractLayout. | |
BAbstractLayout (BMessage *from) | |
Archive constructor. | |
Public Member Functions inherited from BLayout | |
BLayout () | |
Default constructor. | |
BLayout (BMessage *archive) | |
Archive constructor. | |
virtual | ~BLayout () |
Destructor, deletes all BLayoutItem's that this layout manages, and detaches from this BLayout's owner view if there is one. | |
virtual status_t | Perform (perform_code d, void *arg) |
Perform some action (Internal method defined for binary compatibility purposes). | |
BView * | Owner () const |
Returns the Owner of this layout, i.e. the view this layout manages. | |
BView * | TargetView () const |
Returns the target view of this layout. | |
virtual BView * | View () |
Returns the same BView* as BLayout::Owner(), this method is inherited from BLayoutItem. | |
virtual bool | RemoveView (BView *child) |
Removes and deletes all BLayoutItem representing a BView from this layout. | |
virtual bool | RemoveItem (BLayoutItem *item) |
Removes a BLayoutItem from this layout, and also removes the view it represents from this BLayout's target view. | |
virtual BLayoutItem * | RemoveItem (int32 index) |
Remove the BLayoutItem at index. | |
BLayoutItem * | ItemAt (int32 index) const |
Get the BLayoutItem at index. Returns NULL if index is out of bounds. | |
int32 | CountItems () const |
Get the number of BLayoutItem s in this layout. | |
int32 | IndexOfItem (const BLayoutItem *item) const |
Get the index of a BLayoutItem in this layout. | |
int32 | IndexOfView (BView *child) const |
Get the index of child in this layout. | |
virtual void | Relayout (bool immediate=false) |
Request this BLayout to reposition and resize its items as required. | |
void | LayoutItems (bool force=false) |
If there is no layout currently ongoing, and force is false , creates a new BLayoutContext and calls the DoLayout() method of this BLayout and any BLayout's nested in this BLayout. | |
BLayoutContext * | LayoutContext () const |
Returns the BLayoutContext this BLayout is currently operating in, or NULL . | |
bool | AncestorsVisible () const |
Get the visibility of the ancestors of this layout. | |
BRect | LayoutArea () |
Returns the on-screen area this layout has received to lay out its items in. | |
virtual void | InvalidateLayout (bool children=false) |
Invalidate this layout and any cached data this layout has relating to positioning and sizing of its items. | |
void | RequireLayout () |
Flag this layout as stale, i.e. any cached data may still be valid, but the items need to be repositioned or resized. | |
bool | IsValid () |
Returns whether this layout has been invalidated (via BLayout::InvalidateLayout()) and has not yet been validated (by doing a layout, or by its ResetLayoutInvalidation() method. | |
void | EnableLayoutInvalidation () |
Re-enable layout invalidation after a call to DisableLayoutInvalidation(). | |
void | DisableLayoutInvalidation () |
Disable layout invalidation notifications, i.e. calls to this object's InvalidateLayout() method. | |
Public Member Functions inherited from BLayoutItem | |
BLayoutItem (BMessage *from) | |
Archive constructor. | |
virtual status_t | Archive (BMessage *into, bool deep=true) const |
Archive the object into a BMessage. | |
BLayout * | Layout () const |
Returns the BLayout this BLayoutItem resides in. | |
virtual status_t | Perform (perform_code d, void *arg) |
Perform some action (Internal method defined for binary compatibility purposes). | |
bool | RemoveSelf () |
Remove this layout item from the BLayout it is a part of. | |
virtual BView * | View () |
Return the BView this item is representing, or NULL if it does not represent any view. | |
void | SetExplicitSize (BSize size) |
Set the explicity size to size. | |
void | AlignInFrame (BRect frame) |
Position this BLayoutItem within frame, given the value returned by Alignment(), and the size constraints for this item. | |
void * | LayoutData () const |
Retrieve arbitrary data attached to this BLayoutItem. | |
void | SetLayoutData (void *data) |
Attach arbitrary data to this BLayoutItem. | |
Public Member Functions inherited from BArchivable | |
BArchivable () | |
Constructor. Does nothing. | |
BArchivable (BMessage *from) | |
Constructor. Does important behind-the-scenes work in the unarchiving process. | |
virtual | ~BArchivable () |
Destructor. Does nothing. | |
virtual status_t | AllArchived (BMessage *archive) const |
Method relating to the use of BArchiver . | |
virtual status_t | AllUnarchived (const BMessage *archive) |
Method relating to the use of BUnarchiver . | |
virtual status_t | Archive (BMessage *into, bool deep=true) const |
Archive the object into a BMessage. | |
virtual status_t | Perform (perform_code d, void *arg) |
Perform some action (Internal method defined for binary compatibility purposes). | |
Static Public Member Functions | |
static BArchivable * | Instantiate (BMessage *from) |
Instantiate the layout from the message from. | |
Static Public Member Functions inherited from BArchivable | |
static BArchivable * | Instantiate (BMessage *archive) |
Static member to restore objects from messages. | |
Protected Member Functions | |
virtual status_t | AllArchived (BMessage *into) const |
Method relating to the use of BArchiver . | |
virtual status_t | AllUnarchived (const BMessage *from) |
Unarchives the BLayoutItem's for this layout, calling ItemUnarchived() for each one. | |
virtual void | GetColumnRowConstraints (orientation orientation, int32 index, ColumnRowConstraints *constraints) |
Fill in the ColumnRowConstraints for a certain column or row in the BTwoDimensionalLayout. | |
virtual void | GetItemDimensions (BLayoutItem *item, Dimensions *dimensions) |
Tell the base class what column and row a BLayoutItem is in as well as how many columns and rows it covers. | |
virtual int32 | InternalCountColumns () |
Get the number of columns in the BTwoDimensionalLayout. | |
virtual int32 | InternalCountRows () |
Get the number of rows in the BTwoDimensionalLayout. | |
virtual bool | ItemAdded (BLayoutItem *item, int32 atIndex) |
Hook method called when item is added to this layout. | |
virtual status_t | ItemArchived (BMessage *into, BLayoutItem *item, int32 index) const |
Hook for derived classes to add data specific to item to the into BMessage. item resides at index. | |
virtual void | ItemRemoved (BLayoutItem *item, int32 fromIndex) |
Hook method called when item is removed from this layout. | |
virtual status_t | ItemUnarchived (const BMessage *from, BLayoutItem *item, int32 index) |
Hook for derived classes to retrieve data specific to item from the from BMessage. item resides at index. | |
virtual void | PrepareItems (orientation orientation) |
Prepare the BLayoutItem in this BTwoDimensionalLayout subclass for layout within a certain orientation. | |
Protected Member Functions inherited from BTwoDimensionalLayout | |
virtual status_t | AllArchived (BMessage *into) const |
Method relating to the use of BArchiver . | |
virtual status_t | AllUnarchived (const BMessage *from) |
Unarchives the BLayoutItem's for this layout, calling ItemUnarchived() for each one. | |
virtual void | DoLayout () |
Implemented by derived classes to position and resize the items in this layout. | |
virtual status_t | ItemArchived (BMessage *into, BLayoutItem *item, int32 index) const |
Hook for derived classes to add data specific to item to the into BMessage. item resides at index. | |
virtual status_t | ItemUnarchived (const BMessage *from, BLayoutItem *item, int32 index) |
Hook for derived classes to retrieve data specific to item from the from BMessage. item resides at index. | |
virtual void | LayoutInvalidated (bool children=false) |
BSize | AddInsets (BSize size) |
Add the size to all the insets for this layout. | |
void | AddInsets (float *minHeight, float *maxHeight, float *preferredHeight) |
Add to the insets, and store the modified values. | |
BSize | SubtractInsets (BSize size) |
Substract the size from all the insets for this layout. | |
virtual bool | HasMultiColumnItems () |
Tests whether or not this BTwoDimensionalLayout contains any BLayoutItem's spanning more than one column. | |
virtual bool | HasMultiRowItems () |
Tests whether or not this BTwoDimensionalLayout contains any BLayoutItem's spanning more than one row. | |
Protected Member Functions inherited from BAbstractLayout | |
virtual status_t | AllArchived (BMessage *archive) const |
Method relating to the use of BArchiver . | |
virtual status_t | AllUnarchived (const BMessage *from) |
Unarchives the BLayoutItem's for this layout, calling ItemUnarchived() for each one. | |
virtual void | AncestorVisibilityChanged (bool shown) |
Hook method inherited from BLayoutItem, classes derived from BLayout must include the BLayout version of this method in their implementation. | |
virtual void | AttachedToLayout () |
Hook method inherited from BLayoutItem, classes derived from BLayout must include the BLayout version of this method in their implementation. | |
virtual void | DetachedFromLayout (BLayout *layout) |
Hook method inherited from BLayoutItem, classes derived from BLayout must include the BLayout version of this method in their implementation. | |
virtual bool | ItemAdded (BLayoutItem *item, int32 atIndex) |
Hook method called when item is added to this layout. | |
virtual status_t | ItemArchived (BMessage *into, BLayoutItem *item, int32 index) const |
Hook for derived classes to add data specific to item to the into BMessage. item resides at index. | |
virtual void | ItemRemoved (BLayoutItem *item, int32 fromIndex) |
Hook method called when item is removed from this layout. | |
virtual status_t | ItemUnarchived (const BMessage *from, BLayoutItem *item, int32 index) |
Hook for derived classes to retrieve data specific to item from the from BMessage. item resides at index. | |
virtual void | LayoutInvalidated (bool children) |
virtual void | OwnerChanged (BView *was) |
Hook method called when this layout is attached to a BView. | |
Protected Member Functions inherited from BLayout | |
virtual status_t | AllArchived (BMessage *archive) const |
Method relating to the use of BArchiver . | |
void | VisibilityChanged (bool show) |
Method to be called by derived classes in their SetVisible() implementation. Calls AncestorVisibilityChanged() on the items in this BLayout. | |
void | ResetLayoutInvalidation () |
Reset layout invalidation, causing InvalidateLayout calls to proceed again. This method should be called once any cached data has been validated, or updated to valid values. | |
virtual status_t | AllArchived (BMessage *into) const |
Method relating to the use of BArchiver . | |
virtual status_t | AllUnarchived (const BMessage *from) |
Method relating to the use of BUnarchiver . | |
Hook methods |
Additional Inherited Members | |
Protected Attributes inherited from BTwoDimensionalLayout | |
float | fLeftInset |
The current left inset for this layout. | |
float | fRightInset |
The current right inset for this layout. | |
float | fTopInset |
The current top inset for this layout. | |
float | fBottomInset |
The current bottom inset for this layout. | |
float | fHSpacing |
the current horizontal spacing between columns for this layout. | |
float | fVSpacing |
The current vertical spacing between rows for this layout. | |
The BGroupLayout class is a simple BLayout subclass that arranges the items it holds within a vertical or horizontal box.
In a horizontal BGroupLayout, each BLayoutItem is given the same vertical area, but different horizontal areas. In a vertical BGroupLayout, each BLayoutItem is given the same horizontal area, but different vertical areas. Despite this, because of alignment and size constraints, the items in a BGroupLayout may not all use the same vertical or horizontal area on screen. Some BLayoutItems may have alignments that cause them to sit at the bottom of the area they are given, for example. This is not a flaw or bug, but something that you may come across when using this class.
In a BGroupLayout, each BLayoutItem or BView has a weight, the default weight is 1.0f
. When a BGroupLayout is not given enough space to satisfy the minimum sizes of all items, then space is distributed according to weight, while still attempting to satisfy minimum size constraints. Weighting is scaled over the sum weight of all the items in this layout. If a particular item has half of the sum weight of all items, it will get half of the total space, unless this exceeds that item's maximum size. If the space for an item exceeds the items maximum size, the excess will be distributed to other items.
BGroupLayout::BGroupLayout | ( | orientation | orientation, |
float | spacing = B_USE_DEFAULT_SPACING |
||
) |
Creates a new BGroupLayout.
orientation | The orientation of this BGroupLayout. |
spacing | The spacing between BLayoutItems in this BGroupLayout. |
BGroupLayout::BGroupLayout | ( | BMessage * | from | ) |
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virtual |
Destructor method.
Standard Destructor.
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virtual |
Adds item to this layout as the last item. In a vertical BGroupLayout, item will be on the right, in a horizontal BGroupLayout, item will be at the bottom.
item will have a weight of 1.0f
.
Reimplemented from BLayout.
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virtual |
Adds item to the end of this layout with a weight of weight.
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virtual |
Adds item to this layout at index.
item will have a weight of 1.0f
.
Reimplemented from BLayout.
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virtual |
Adds item this layout at index with a weight of weight.
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virtual |
Adds child to this layout as the last item. In a vertical BGroupLayout, child will be on the right, in a horizontal BGroupLayout, child will be at the bottom.
child will have a weight of 1.0f
.
Reimplemented from BLayout.
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virtual |
Adds child to the end of this layout with a weight of weight.
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virtual |
Adds child to this layout at index.
child will have a weight of 1.0f
.
Reimplemented from BLayout.
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virtual |
Adds child this layout at index with a weight of weight.
Method relating to the use of BArchiver
.
This hook function is called once the first BArchiver that was created in an archiving session is either destroyed, or has its Finish() method called. Implementations of this method can be used, in conjunction with BArchiver::IsArchived(), to reference objects in your archive that you do not own, depending on whether or not those objects were archived by their owners. Implementations of this method should call the implementation of their parent class, the same as for the Archive() method.
Reimplemented from BTwoDimensionalLayout.
Unarchives the BLayoutItem's for this layout, calling ItemUnarchived() for each one.
Reimplemented from BTwoDimensionalLayout.
Archives this layout into archive. If deep is true, also archives the items in this layout, calling ItemArchived() for each one.
Reimplemented from BTwoDimensionalLayout.
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protectedvirtual |
Fill in the ColumnRowConstraints for a certain column or row in the BTwoDimensionalLayout.
This method is used to communicate the size constraints and weight for a given row/column in the BTwoDimensionalLayout.
Implements BTwoDimensionalLayout.
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protectedvirtual |
Tell the base class what column and row a BLayoutItem is in as well as how many columns and rows it covers.
Implements BTwoDimensionalLayout.
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static |
Instantiate the layout from the message from.
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protectedvirtual |
Get the number of columns in the BTwoDimensionalLayout.
Implements BTwoDimensionalLayout.
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protectedvirtual |
Get the number of rows in the BTwoDimensionalLayout.
Implements BTwoDimensionalLayout.
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protectedvirtual |
Hook method called when item is added to this layout.
item | The BLayoutItem that is being added. |
atIndex | The index of the BLayoutItem. |
true
on succcess, false if item will not be added.Reimplemented from BAbstractLayout.
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protectedvirtual |
Hook for derived classes to add data specific to item to the into BMessage. item resides at index.
Reimplemented from BTwoDimensionalLayout.
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protectedvirtual |
Hook method called when item is removed from this layout.
item | The BLayoutItem being removed. |
fromIndex | The index where item used to reside. |
When this hook is called, item is not yet completely removed. It can no longer be accessed with LayoutItemAt(), nor does it contribute to the value of CountItems(), but the item has not yet had its ItemDetached() hook called.
Reimplemented from BAbstractLayout.
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protectedvirtual |
Hook for derived classes to retrieve data specific to item from the from BMessage. item resides at index.
Reimplemented from BTwoDimensionalLayout.
float BGroupLayout::ItemWeight | ( | int32 | index | ) | const |
Get the weight of the item at index.
orientation BGroupLayout::Orientation | ( | ) | const |
Get the orientation of this BGroupLayout.
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virtual |
Perform some action (Internal method defined for binary compatibility purposes).
Reimplemented from BTwoDimensionalLayout.
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protectedvirtual |
Prepare the BLayoutItem in this BTwoDimensionalLayout subclass for layout within a certain orientation.
This is a good place to update cache information that will be used in other hook methods, for example.
Reimplemented from BTwoDimensionalLayout.
void BGroupLayout::SetItemWeight | ( | int32 | index, |
float | weight | ||
) |
Set the weight of the item at index.
void BGroupLayout::SetOrientation | ( | orientation | orientation | ) |
Set the orientation of this BGroupLayout.
orientation | The new orientation of this BGroupLayout. |
void BGroupLayout::SetSpacing | ( | float | spacing | ) |
Set the amount of spacing (in pixels) between each item.
float BGroupLayout::Spacing | ( | ) | const |
Get the amount of spacing (in pixels) between each item.