Add custom bitmap to new toolbar button

There is an existing toolbar created with CreateToolBarEx and I have added a button after the creation of this toolbar with the TB_ADDBUTTONS message and a TBBUTTON struct containing my new button's information. I need to be able to modify the imagelist of this toolbar and add a custom bitmap to it, then assign my button this new image index which I would do in the iBitmap member of the TBBUTTON struct prior to adding my new button I would assume. I need some code which can do this because I am having problems doing this.

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