Problems dynamically updating xul hierarchical trees dating site admin panel facebook

Empty containers will not have a twisty, but will still be treated like a container.

When the user clicks the twisty to open a row, the tree will call the view's function is used as optimization to only start looking for the next sibling after that point.

This blog post is motivated by an interesting problem I solved today: Timus 1846.

I knew about segment trees previously for solving range-minimum query, but was not fully aware of the obvious generalizations of this nice data structure.

First, the simple functions: tree Box: null, selection: null, get row Count() , set Tree: function(tree Box) , get Cell Text: function(idx, column) , is Container: function(idx) , is Container Open: function(idx) , is Container Empty: function(idx) , is Separator: function(idx) , is Sorted: function() , is Editable: function(idx, column) , should be three, even though six rows are hidden.

Also note the use of the Java Script get operator to bind a property to a function, so to have the value of the row Count property that can change dynamically over time, as row Count has to be a read-only attribute as defined in ns ITree View.

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All of these methods must be implemented by the view for children to be handled properly. A container may be rendered differently than a non-container.

For instance, the caller might already know where the next sibling might possibly be.

Imagine a situation where a row had subrows and those subrows had child rows of their own and several are open.

This is a fairly tricky process as it involves keeping track of which items have children and also which rows are open and closed. The topmost rows are at level 0, the children of those rows are at level 1, their children at level 2 and so on.

The tree will query the view for each row by calling its method to find out the level of that row.

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