public void addRetained(EngineLayer retainedLayer)
{
D.assert(retainedLayer is _EngineLayerWrapper);
D.assert(() => {
_EngineLayerWrapper layer = retainedLayer as _EngineLayerWrapper;
void recursivelyCheckChildrenUsedOnce(_EngineLayerWrapper parentLayer)
{
_debugCheckUsedOnce(parentLayer, "retained layer");
parentLayer._debugCheckNotUsedAsOldLayer();
if (parentLayer._debugChildren == null || parentLayer._debugChildren.isEmpty())
{
return;
}
parentLayer._debugChildren.ForEach(recursivelyCheckChildrenUsedOnce);
}
recursivelyCheckChildrenUsedOnce(layer);
return(true);
});
_EngineLayerWrapper wrapper = retainedLayer as _EngineLayerWrapper;
SceneBuilder_addRetained(_ptr, wrapper._ptr);
}
bool _debugCheckUsedOnce(EngineLayer layer, string usage)
{
D.assert(() => {
if (layer == null)
{
return(true);
}
D.assert(
!_usedLayers.ContainsKey(layer),
() => $"Layer {layer.GetType()} already used.\n" +
$"The layer is already being used as {_usedLayers[layer]} in this scene.\n" +
"A layer may only be used once in a given scene.");
_usedLayers[layer] = usage;
return(true);
});
return(true);
}
/// Add a retained engine layer subtree from previous frames.
///
/// All the engine layers that are in the subtree of the retained layer will
/// be automatically appended to the current engine layer tree.
///
/// Therefore, when implementing a subclas of the [Layer] concept defined in
/// the rendering layer of Flutter's framework, once this is called, there's
/// no need to call [addToScene] for its children layers.
public EngineLayer addRetained(EngineLayer retainedLayer)
{
// native 'SceneBuilder_addRetained';
return(null); // Tmp to resolve build
}