# Operating Controls

A control is an object that resides on a panel to accept input from the user and to display information. The User Interface Library supports the following control types:

- Numeric
- Color Numeric
- Numeric Slide
- String
- Text Message
- Text Box
- Command Button
- Picture Button
- Toggle Button
- Text Button
- Radio Button
- LED
- Binary Switch
- Ring
- Ring Slide
- Picture Ring
- List Box
- Tree
- Decoration
- Graph
- Strip Chart
- Digital Graph
- Picture
- Timer
- Canvas
- Table
- Splitter
- Tab
- ActiveX

To make a control ready to accept input, click on the control with the mouse or press <Tab> or <Shift-Tab> to move from control to control. Pressing <Alt> and the underlined letter in the label of the control makes that control ready to accept input, provided that no accessible menu bars contain a menu with the same underlined letter. On some controls, such as command buttons, pressing <Alt> and the underlined letter generates a commit event.

## Data Types of Controls

Every control has a data type associated with it. The data type of the control determines the data type of variables used to set and obtain the value of the control. The following list shows LabWindows/CVI control data types:

unsigned char
char
char *
unsigned short int
short int
unsigned long int
long int
float
double

Not all data types are valid for each type of control.

Programming Controls