Constructor.

Virtual destructor.

Two-phased constructor, which attach new object into the control.

Anchors one or more edges of a child visual to a specific position within this layout. When combined together, a correctly specified group of anchors provide sufficient information for the anchor layout to determine the size and position of the child visual.

Each child can have up to four anchors, each of which correspond to an edge. A corner anchor is equivalent to supplying two similar orthogonal edge anchors, so typically it is easier to use corners. Therefore, each child can have up to two corner anchors, or a mixture of corners and edges. Alternatively, four similar edges can be specified in one call by supplying a box metric.

In a typical case you set two different corner anchors (for example both EAlfAnchorTypeTopLeft and EAlfAnchorTypeBottomRight), taking care to ensure that they are sufficiently orthogonal in order to define all needed coordinates. However it is also possible to set only one corner anchor, which only positions the child without affecting it's size. Alternatively, one anchor can be specified as a corner, and then the other can be specified as EAlfAnchorTypeSize; similarly the coordinates along one axis can be specified by an appropriate combination of edge and width or height anchors.

The position of each anchor relative to this layout is determined by the choice of origin (i.e. which point of the layout the child's is attached to), and the offset position, which is specified using a TAlfMetric or related type. All available features of TAlfMetric may be used to affect the resulting position, providing the benefit that different metrics can be used for each child. Also note that the metric used will override the base unit that has been set in this layout.

      // using edges...
	    iLayout->Attach(0, 
          EAlfAnchorTypeLeft,
          TAlfXYMetric(0.25, EAlfMetricNormalized),
          EAlfAnchorAttachmentOriginLeft);
	    iLayout->Attach(0, 
          EAlfAnchorTypeRight,
          TAlfXYMetric(-0.25, EAlfMetricNormalized),
          EAlfAnchorAttachmentOriginRight);
	    iLayout->Attach(0, 
          EAlfAnchorTypeTop,
          TAlfXYMetric(0.25, EAlfMetricNormalized),
          EAlfAnchorAttachmentOriginTop);
	    iLayout->Attach(0, 
          EAlfAnchorTypeBottom,
          TAlfXYMetric(-0.25, EAlfMetricNormalized),
          EAlfAnchorAttachmentOriginBottom);

      // using corners...
	    iLayout->Attach(1, 
          EAlfAnchorTypeTopLeft,
          TAlfXYMetric(0.25, EAlfMetricNormalized),
          EAlfAnchorAttachmentOriginTopLeft);
 	    iLayout->Attach(1, 
	        EAlfAnchorTypeBottomRight, 
         TAlfXYMetric(-0.25, EAlfMetricNormalized),
	        EAlfAnchorAttachmentOriginBottomRight);
 
      // .. and using a box
 	    iLayout->Attach(2, TAlfBoxMetric(
          TAlfMetric(0.25, EAlfMetricNormalized),
          TAlfMetric(-0.25, EAlfMetricNormalized),
          TAlfMetric(0.25, EAlfMetricNormalized),
          TAlfMetric(-0.25, EAlfMetricNormalized)));

Attach a corner of a child visual to a specific position within this layout.

Attach() for all API documentation

Attach all four edges of a child visual to a specific position within this layout.

From CAlfLayout CAlfLayout

From CAlfLayout. Second-phase constructor.

Undefines all anchors for a specified ordinal. Has no effect if the specified ordinal cannot be found.

Attach()

Undefines an anchor. Has no effect if the specified anchor type cannot be found. For example to detach a corner anchor with ordinal equal to zero:

      iLayout->Detach(0, EAlfAnchorTypeTopLeft);

From CAlfVisual CAlfVisual

CAlfVisual Finds a visual whose tag descriptor contains a specific tag.

CAlfLayout::FindTag() extends the search into child visuals, covering recursively entire visual hierarchies.

Todo: how should several visuals with matching tag to be handled ??

CAlfVisual::Tag() CAlfVisual::SetTagL() CAlfVisual::IsTagged() CAlfVisual::FindTag()

! future proofing

Undefines an anchor. SetAnchor() instead use Detach and see relevant API documentation for example code

From CAlfVisual CAlfVisual

Resets all the anchors.

Anchors a child visual's corner to specific position within this layout.

, use new Attach APIs with TAlfMetric support. See the relevant API documentation for an example of how to migrate your code

Each child can have two anchors: the top left and bottom right corners of the child visual. These anchors can be fastened to any point within this layout, as specified by the other parameters.

In a typical case you set two anchors (both EAlfAnchorTopLeft and EAlfAnchorBottomRight), which specifies both size and position for the child. However it is also possible to set only the EAlfAnchorTopLeft anchor, which only positions the child without affecting it's size.

      // set top left corner position of 1st child ..
	    iLayout->SetAnchor(EAlfAnchorTopLeft, 0,
	        EAlfAnchorOriginLeft, 
          EAlfAnchorOriginTop,
          EAlfAnchorMetricRelativeToSize, // With EAlfAnchorOriginLeft means that 0.0 goes to left edge, and 1.0 to the right
          EAlfAnchorMetricRelativeToSize, // With EAlfAnchorOriginTop means that 0.0 goes to top edge, and 1.0 to the bottom
          TAlfTimedPoint(0.25, 0.25));
      // .. and set the bottom right corner also to fix the size
 	    iLayout->SetAnchor(EAlfAnchorBottomRight, 0,
	        EAlfAnchorOriginRight, 
          EAlfAnchorOriginBottom,
   	EAlfAnchorMetricRelativeToSize, 
          EAlfAnchorMetricRelativeToSize,
          TAlfTimedPoint(-0.25, -0.25)); 

TodoSpecifying a transition in the timed point may be useless: layouts are evaluated pretty seldom.

Convenience method for setting top left and bottom right anchors in a single call.

This method sets size-relative anchors for a single child visual.

CAlfAnchorLayout::SetAnchor() for more information about anchors.

CAlfVisual Update the layout of all children. Subclasses can call this to recalculate the layout of all children.