TextChanged is an overridden method in TCustomFloatSpinEdit. It ensures that internal flags are updated to track the value and state for the control when it has been changed. It calls the inherited method to validate the content in Text and update the caret position for the control.

Loaded calls the inherited method on entry to determine the size for the control (and its children) and to apply property values inherited from the parent control (when assigned). Loaded calls the private UpdateControl method when the internal update flag has been set for the control.

KeyPress is an overridden method used to handle key press events for the control. KeyPress calls the inherited method on entry. If the character in Key is not handled in the ancestor class, the argument is examined to determine if it is valid for the control. If Key is not a valid character, it is set to #0 to ignore the key press event.

KeyPress disallows any value in Key that is not a numeric digit, sign character ('+' or '-'), or decimal point character ('.' or ','). The decimal point is automatically converted to the value used in the DefaultFormatSettings variable from the RTL. The decimal point is not allowed when Decimals is set to 0 (zero).

KeyPress does not ensure that the value in Key is valid for a specific position in the control value. It does not guarantee that sign indicators are used only at the start of the control value. Nor does it guarantee that a decimal point character is not used more than once in the entered value. This is implemented in a manner that is Delphi compatible.

Tab (#9), BackSpace (#8), Cut (^X), Paste (^V), Copy (^C), and Undo (^Z) characters are allowed in Key so that they may be applied in inherited methods for the control.

Create is the overridden constructor for the class instance, and calls the inherited method on entry. Create sets the style flags needed for the spin edit control, and sets the default values for properties in the class instance. The GetControlClassDefaultSize method is called and the return value is used to set the initial size for the control.

The return value is set to AValue and limited to the range in the MinValue and MaxValue properties. This occurs when MaxValue has a value that is larger than MinValue. No constraints are applied when MinValue and MaxValue have the the same value, or when MaxValue is smaller than MinValue.

Called from the UpdateControl, StrToValue, and ValueToStr methods.

Calls GetLimitedValue to range limit the value in AValue. Calls FloatToStrF to format the return value using 20 digits of precision and the number of decimals in the DecimalPlaces property.

Calls StrToFloatF to convert the value in S to a Double data type. If S contains an invalid representation for a float value, Value is used as the return value for the method.

DecimalPlaces is used in the ValueToStr method, and determines the decimal precision for the value displayed in the spin edit control.

EditorEnabled is a Boolean property which indicates if the Value for the control can be input directly. When set to True, the edit box is enabled. When set To False, only the up and down arrow buttons can be used to change the Value for the control.

The default value for the property is True. Changing the value for the property causes the widgetset class to be notified when the Handle for the control has been allocated.

EditorEnabled is independent of the settings in the ReadOnly and Enabled properties. When ReadOnly is set to True, the Value for the control cannot be modified using either the edit box or the up / down buttons. When Enabled is set to False, the control cannot be given focus or modified.

The default value for the property is defined in the DefIncrement constant (1). Changing the value for the property causes the UpdateControl method to be called.

Minimal value allowed for the spin edit control. Set the MinValue property equal to MaxValue to allow any number to be selected.

Maximal value allowed for the spin edit control. Set the MinValue property equal to MaxValue to allow any number to be selected.

Value is a Double property which contains the value for the spin edit control. Its content can be modified using the UI elements for the control (up and down buttons, up and down cursor keys, edit box for the control). It can also be directly assigned in program code.

Changing the value for the property causes the Text for the control to be checked for a valid numeric representation in the property. If the new property value is the same as the existing value, no actions are performed.

When the property value has been stored, internal flags are set to ensure that Modified is updated accordingly and the private UpdateControl method is called. If the handle for the control has been allocated, the Change method is called to post a CM_CHANGED control message and signal OnChange handler(s) assigned for the control.

Value is constrained to the range defined in the MinValue and MaxValue properties.

TFloatSpinEdit is a TCustomFloatSpinEdit descendant which implements a spin edit control for a Float value. It provides an edit control for the numeric value and up / down buttons that can be clicked to increment or decrement the Value for the control. TFloatSpinEdit sets the visibility for properties introduced in ancestor classes.

Use TSpinEdit to edit an Integer value.

AutoSelected is updated in methods which handle focus change actions for the control, including: MouseDown, MouseUp, DoEnter, and DoExit. In general, it indicates when the Text and SelText properties have the same value.

The visibility for the property is public, and does not appear in the Object Inspector at design-time. It is, however, available in code at run-time. It is not declared as a read-only property, but there is no obvious reason to assign a value that does not result from calling the SelectAll method.

Use AutoSelect to control whether auto-selection is enabled for the control.