Programming WPF, 2nd Edition

Slider and Scroll Controls

WPF provides controls that allow a value to be selected from a range. They all offer a similar appearance and usage: they show a track, indicating the range, and a draggable "thumb" with which the value can be adjusted. There is the Slider control, shown in Figure 5-6, and the ScrollBar control, shown in Figure 5-7. The main difference is one of convention rather than functionality—the ScrollBar control is commonly used in conjunction with some scrolling viewable area, and the Slider control is used to adjust values.

Figure 5-6. Horizontal and vertical sliders

Figure 5-7. Horizontal and vertical scroll bars

Slider and ScrollBar are very similar in use. Both controls have an Orientation property to select between vertical and horizontal modes. They both derive from a common base class, RangeBase. This provides Minimum and Maximum properties, which define the range of values the control represents, and a Value property holding the currently selected value. It also defines SmallChange and LargeChange properties, which determine by how much the Value changes when adjusted with the arrow keys, or the Page Up and Page Down keys, respectively. The LargeChange value is also used when the part of the slider track on either side of the thumb is clicked.

Whereas slider controls ...