TrackBar
control is one of the useful user interface control, commonly used to select a value from the given range, by using it’s slider (or thumb) or by using keyboard keys. For example, if you want to set the brightness of the screen, using your program, you can use this control as an interface element and attach to the background logic to set the brightness of the screen whenever the control’s value changed.
Properties
By using TrackBar
control’s Minimum
& Maximum
properties, we can set the boundaries of the values (range) the user can select using this control. The values are integer values. Lower limit of the range, set through Minimum
property & upper limit of the range, set through it’s Maximum
property.
TrackBar
control provides a slider to allow the user to select the value from the set range, of the control. When the user moves the slider, control’s Value
property will be changed to keep the current value of the control. User can move the slider using the Mouse or Keyboard keys.
Note that, the value set, must be with in the set range; otherwise, the control will throw the Error; “System.ArgumentOutOfRangeException”. ‘Value’ should be between ‘Minimum’ and ‘Maximum’.
Another useful, SmallChange
& LargeChange
properties to control the number of positions the slider moves when the user press the keys on the keyboard. SmallChange
property controls the number of positions of the slider, when the user press the arrow keys on the keyboard; whereas LargeChange
property controls when the user clicks the mouse or press the Page Up
/ Page Down
keys from the keyboard.
Tick marks also will be displayed on the control to indicate the position of the slider. TickStyle
property is used to control these tick marks. It controls where to display the tick marks on the control; whether BottomRight
or TopLeft
or Both
sides of the control. By setting, None
value to this property, we can hide the tick marks on the control.
When tick marks are visible by setting TickStyle
property, another property we can use is TickFrequency
to set the number of positions between the tick marks.
By using Orientation
property, we can display the control Horizontal
or in Vertical
direction.
Methods
TrackBar
control’s SetRange
method is useful to set the Minimum & Maximum values for the control. We can set the range of values for the control, by using above mentioned Minimum
& Maximum
properties or by calling this SetRange
method.
Events
When the TrackBar
control’s value is changed, it triggers ValueChanged
event.
Complete working code
Now this is the time to put all the things we discussed so far, together in one place and finally here is the working example;
Designer C# file
C# code file
Upon successful execution of the code, you will see the Application window, like below;
(Raju)