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CheckBox Class
+ Object
+ Display
+ UIComponent
+ Control
+ ActionControl
+ CheckBox
Description
The CheckBox class implements the behaviours specific to checkboxes. This type of control offers the user a choice of yes or no. This class is not instantiable, derivable or cloneable. The only instances available to the programmer are those automatically generated by HB++ when you place a control on a form.
The Text and Font properties inherited by the ActionControl class modify respecitively the text and font displayed by the control whilst the Value property returns or modifies the control state.
When you modify the text displayed at runtime, the control is automatically resized to fit the new text. The value of the AnchorLeft property specifies whether the left or right edge is fixed or resized. Typically, you will set this property to True when the control is close to the lefthand side of the screen and False when it is close to the righthand side. This way, the control will always be fully visible.
The CheckBox controls can be grouped together. Each group is identified by a non null value, entered at design time in the Group property of each control. Within each group, only one checkbox can be checked at a time. It is not recommended to use mutually exclusive checkboxes. If you want to offer one choice from several options to the user, you should use a PushButton or Popup controls.
Note : the PenMove event is not raised by this object but handled internally.
Members
| Inherited from ActionControl | Description |
| Click | Raised when the user taps a control. |
| Font | Font used to display the control text. |
| Group | Group which the control belongs to. |
| HitControl | Simulates a tap on a control. |
| Text | Text displayed by the control. |
| Value | Control state. |
| Inherited from Control | Description |
| DrawFocusRing | Draws the focus ring. |
| GotFocus | Event raised when the control gains the focus. |
| Layer | Layer to which the control belongs. |
| LostFocus | Event raised when the control loses the focus. |
| NavFlags | Navigation flags for the control. |
| RemoveFocusRing | Erase the focus ring. |
| Tag | String associated with the control. |
| Visible | Indicates if a control is visible or not. |
| Inherited from UIComponent | Description |
| ComponentToScreen | Converts coordinates relative to a component into coordinates relative to the screen. |
| FiveWayNavigator | Event raised when the user presses one of the 5-way navigator keys. |
| Height | Element height. |
| Left | Distance between the left edge of the form and the left edge of the element. |
| Move | Moves or resizes an element. |
| PenDown | Event raised when the user touches an UI element with the stylus. |
| PenMove | Event raised when the user moves the stylus. |
| PenUp | Event raised when the user releases the stylus. |
| ScreenToComponent | Converts coordinates relative to the screen into coordinates relative a component. |
| Top | Distance between the top edge of the form and the top edge of the element. |
| UIRef | Internal reference to a control. |
| Width | Element width. |
| Inherited from Display | Description |
| Arc | Draws an arc. |
| BackColor | Background color. |
| BatchLimit | Size of the graphics instruction buffer. |
| CoordinateSystem | Coordinates system. |
| CopyArea | Efficiently copies part of a Display object to another. |
| DrawFont | Font used to draw the text. |
| Flush | Empties the graphics instruction buffer. |
| FontMetrics | Returns a FontMetrics object describing the physical charateristics of the currently active font. |
| ForeColor | Foreground color. |
| GetPixel | Queries the color of a given pixel. |
| hWin | Returns the window handle. |
| Line | Draws a line. |
| Oval | Draws a circle or ellipse. |
| Pattern | Defines the pattern used to fill drawings. |
| Polygon | Draws a polygon. |
| PutPixel | Sets the color of a pixel. |
| Rectangle | Draw a rectangle. |
| ResID | Identifier of the resource associated with the object. |
| ScaleFont | Enable or disable font scaling. |
| TextColor | Text color. |
| TextOut | Draw text. |
| Inherited from Object | Description |
| ClassID | Returns the type identifier corresponding to the actual class of the object. |
| Implements | Determines whether the object implements the features of a given class. |
| Iterate | Event raised to iterate over the elements of a container object. |
| Recipient | Recipient of events sent by the object. |
| Serialize | Event raised to serialize the object content into a stream. |
System requirements
| System | Minimal version | Remarks |
| Palm OS | Palm OS 3.0 | N/A |