Custom TreeModel implementations (that are Trees) broken

[mlizard32]

When creating a custom tree model that is a Tree(not a simple list) like in Demos\gtkD\DemoCustomList, the model will crash when trying to expand child nodes.

in TreeModelIF.d "iterChildren" "iterHasChild" etc changed from
public bool iterChildren(TreeIter iter, TreeIter parent);
to
public bool iterChildren(out TreeIter iter, TreeIter parent);

when I revert related changes my custom TreeModel works fine with children.

gtk 3.18, windows

[MikeWey]

This change happened in the 3.0 release.

Initializing the iter in your implementation of iterChildren should fix the problem.

[mlizard32]

I see in the gtk docs that iter_children has "iter" marked as "out", but I'm not seeing that behavior in the gtk3
the following is currently working for me.

override bool iterChildren(TreeIter iter, TreeIter parent)
    {
        RMObject rmObj;
        RMObject parentObj;

assert(iter !is null) //iter passed in is not uninitialized like expected
        if ( parent is null )
        {
            rmObj = cast(RMObject)root.getChildren[0];
        }
        else
        {
            parentObj = cast(RMObject)parent.userData;

            auto children = parentObj.getChildren;

            if(children.length == 0)
                return false;

            rmObj = cast(RMObject) children[0];
        }
        /* Set iter to first item in list */
        iter.stamp     = stamp;
        iter.userData  = cast(void*)rmObj;

        return true;
    }

when doing it this way

override bool iterChildren(out TreeIter iter, TreeIter parent)
    {
        RMObject rmObj;
        RMObject parentObj;
assert(iter !is null) //iter passed in is not uninitialized like expected
        if ( parent is null )
        {
            rmObj = cast(RMObject)root.getChildren[0];
        }
        else
        {
            parentObj = cast(RMObject)parent.userData;

            auto children = parentObj.getChildren;

            if(children.length == 0)
                return false;

            rmObj = cast(RMObject) children[0];
        }

        iter = new TreeIter(); //initializing new Iter
        iter.stamp     = stamp;
        iter.userData  = cast(void*)rmObj;

        return true;
    }

it breaks later in iterParent because the child passed into iterParent is invalid

When initializing the Tree Model, I initialize TreeIter for every node in my tree including children
like this

void appendObj(RMObject obj)
    {
        TreeIter iter;
        TreePath path;

//this can be a path with depth(ie child)
        path = getPathFromObject(obj);
        assert(path !is null);
        iter = new TreeIter();
        getIter(iter, path);

        rowInserted(path, iter);
    }

maybe that is where i'm going wrong, but it doesn't make sense to me to allocate a new iterator everytime you iterate through children.

[MikeWey]

Does commit 8ce74d8 make any difference with this issue?