The Hierarchy of Splitters
The front panel of any VI initially has a single pane that fills the window. The front panel owns this pane, serving as the pane's parent. Each time you drop a splitter onto a pane, it replaces the pane in the hierarchy and creates two new panes. The new splitter owns these two panes. For example, if you drop a splitter on a new VI, the splitter replaces the old pane, and the front panel now owns the splitter. The splitter, in turn, owns two panes. If you then drop a new splitter on one of these panes, it replaces that pane the top-level splitter's child, and is a parent to two new panes. This hierarchy forms a binary tree, and the front panel owns the top node.
Once you have laid out your desired set of panes and splitters on the front panel, you must decide how the layout will interact with the user. Which panes will grow when the user resizes the window? Should the user be able to resize all the panes on the front panel? What will the objects on each pane do as the user resizes the panes?
You can configure splitters and panes by accessing the shortcut menu of the splitter or by using Property Nodes. In addition, if there are no splitters on the front panel, you can configure several options for the single pane in the VI property pages.
The splitter sizing and pane sizing submenus offer options for the behavior of these objects when the user resizes the window or moves a parent splitter. You can make the splitter maintain its distance to the edge of either child, or you can have the splitter maintain the ratio in size between its two children. For example, if you have a front panel with one vertical splitter, and its sizing property is set to Sticks to Left, the left pane will not change size when you resize the window's width. If you shrink the window from the right, the splitter will not move. If you shrink the window from the left, the splitter will move as far as you move the left edge of the window, to maintain its distance to the left edge.
You also can configure how controls on a pane react when the user resizes the pane. If you want the controls on a pane to maintain their position relative to a particular edge of the pane, select the item in the Pane Sizing submenu that corresponds to that edge. For example, to make the controls on a pane maintain their distance to the right edge of the pane, select Origin Sticks Right. You also can make controls scale their bounds with the bounds of the pane. You have the option of selecting one control to scale with the pane, or making all objects on the pane scale. If you have only one control on a pane, you can make it scale to fill the pane.
Using Splitters to Create a Toolbar
Splitters add the powerful ability to create toolbars on front panels that you can configure with any LabVIEW control. A toolbar is merely a region (pane) set aside to hold frequently used controls, while the rest of the application is free to change (by scrolling, for example).
To create a toolbar at the top of your VI, simply place a horizontal splitter on the front panel, and place a set of controls in the upper pane. A useful configuration would keep the splitter locked and set to Sticks to Top, with the upper pane's scrollbars set to Always Off. You also can paint the pane and size the splitter to make the pane blend seamlessly with the menu bar. Meanwhile, the lower pane is free to scroll, or can be further split, without affecting the controls on the toolbar.
Using Splitters to Create a Status Bar
You can use splitters to create a status bar very similarly to using a splitter to create a toolbar (see section above). In this case, however, the splitter should be set to Sticks to Bottom and placed near the bottom of the front panel.