NAME

SYNOPSIS

#include <agar/core.h>
#include <agar/gui.h>

DESCRIPTION

INHERITANCE HIERARCHY

INTERFACE

AG_Button *
AG_ButtonNewS(AG_Widget *parent, Uint flags, const char *label);

AG_Button *
AG_ButtonNewFn(AG_Widget *parent, Uint flags, const char *label, void (*fn)(AG_Event *), const char *fnArgs, ...);

AG_Button *
AG_ButtonNew{Int,Uint8,Uint16,Uint32}(AG_Widget *parent, Uint flags, const char *label, <Type> *p);

AG_Button *
AG_ButtonNew{Flag,Flag8,Flag16,Flag32}(AG_Widget *parent, Uint flags, const char *label, Uint *p, <Type> bitmask);

void
AG_ButtonSetPadding(AG_Button *button, int lPad, int rPad, int tPad, int bPad);

void
AG_ButtonSetFocusable(AG_Button *button, int flag);

void
AG_ButtonSetSticky(AG_Button *button, int flag);

void
AG_ButtonInvertState(AG_Button *button, int flag);

void
AG_ButtonJustify(AG_Button *button, enum ag_text_justify justify);

void
AG_ButtonValign(AG_Button *button, enum ag_text_valign valign);

void
AG_ButtonSetRepeatMode(AG_Button *button, int repeat_flag);

void
AG_ButtonSurface(AG_Button *button, const AG_Surface *su);

void
AG_ButtonSurfaceNODUP(AG_Button *button, AG_Surface *su);

void
AG_ButtonText(AG_Button *button, const char *format, ...);

void
AG_ButtonTextS(AG_Button *button, const char *label);

The AG_ButtonNew() function allocates, initializes, and attaches a AG_Button widget. If the label argument is given, it sets a default text caption. For the list of acceptable flags, see BUTTON FLAGS section.

The AG_ButtonNewFn() variant creates a button and implicitely sets a callback (event handler) function to be executed whenever the button is pressed. See AG_Event(3) for details on Agar event handlers. Since function-triggering buttons rarely make use of the "state" binding, AG_ButtonNewFn() implies AG_BUTTON_EXCL (unless AG_BUTTON_NOEXCL is passed).

The AG_ButtonNew{Int,Uint8,Uint16,Uint32}() functions tie the state of the button (the ‘state’ binding) with the given integer variable, where 1 = True and 0 = False.

The AG_ButtonNew{Flag,Flag8,Flag16,Flag32}(), functions tie the state of the button with the state of the bits described by bitmask in the specified integer variable. AG_ButtonNewFlag() binds to an int, AG_ButtonNewFlag8() binds to an Uint8, etc.

The AG_ButtonSetPadding() function sets the padding around the label in pixels. If a parameter is -1, its current value is preserved. Note that when using a text label, this setting is independent from that of the label (use AG_LabelSetPadding(3) on the lbl member of the AG_Button to configure the text label padding as well).

The AG_ButtonSetFocusable() function with an argument of 0 prevents the button from gaining focus. The default is to allow buttons to gain focus.

The AG_ButtonSetSticky() function enables or disable sticky mode. Under sticky mode, the button will not spring back to its previous state following a click event. This mode is mostly useful when the button's state is bound to a boolean variable.

The AG_ButtonInvertState() function defines whether to invert the meaning of the boolean variable bound to the button.

AG_ButtonJustify() sets the justification for the button text label (or icon):

enum ag_text_justify {
	AG_TEXT_LEFT,
	AG_TEXT_CENTER,
	AG_TEXT_RIGHT
};

AG_ButtonValign() sets the vertical alignment for the button text label (or icon):

enum ag_text_valign {
	AG_TEXT_TOP,
	AG_TEXT_MIDDLE,
	AG_TEXT_BOTTOM
};

The AG_ButtonSetRepeatMode() flag enables or disables repeat mode. Repeat mode causes multiple ‘button-pushed’ events to be posted periodically for as long as the button is triggered. Repeat mode is used notably by AG_Numerical(3).

AG_ButtonSurface() sets the button label to a copy of the given surface. The AG_ButtonSurfaceNODUP() variant uses the given surface as source without copying. If a text label currently exists, it is removed.

AG_ButtonText() sets the label of the button from the specified text string. If a surface is currently set, it is removed.

BUTTON FLAGS

AG_BUTTON_STICKY

Prevent the button from springing back to its previous state following a click. Set on initialization or by AG_ButtonSetSticky().

AG_BUTTON_MOUSEOVER

The cursor is over the button area (read-only).

AG_BUTTON_REPEAT

Repeat mode is enabled (read-only, see AG_ButtonSetRepeatMode()).

AG_BUTTON_INVSTATE

Invert the interpretation of the "state" binding. By default, a value of 1 causes the button to be pressed.

AG_BUTTON_EXCL

Disable the test for redrawing the button upon external changes to the "state" binding.

AG_BUTTON_HFILL

Expand horizontally in parent (equivalent to invoking AG_ExpandHoriz(3)).

AG_BUTTON_VFILL

Expand vertically in parent (equivalent to invoking AG_ExpandVert(3)).

AG_BUTTON_EXPAND

Shorthand for AG_BUTTON_HFILL|AG_BUTTON_VFILL.

EVENTS

button-pushed(int new_state)

The button was pressed. If using AG_BUTTON_STICKY, the new_state argument indicates the new state of the button.

BINDINGS

BOOL *state

Value (1/0) of natural integer

INT *state

Value (1/0) of natural integer

UINT8 *state

Value (1/0) of 8-bit integer

UINT16 *state

Value (1/0) of 16-bit integer

UINT32 *state

Value (1/0) of 32-bit integer

FLAGS *state

Bits in an int

FLAGS8 *state

Bits in 8-bit word

FLAGS16 *state

Bits in 16-bit word

FLAGS32 *state

Bits in 32-bit word

EXAMPLES

void
MyHandlerFn(AG_Event *event)
{
	AG_TextMsg(AG_MSG_INFO, "Hello, %s!", AG_STRING(1));
}

...


AG_ButtonNewFn(parent, 0, "Hello", MyHandlerFn, "%s", "world");

The following code fragment uses buttons to control specific bits in a 32-bit word:

Uint32 MyFlags = 0;

AG_ButtonNewFlag32(parent, 0, "Bit 1", &MyFlags, 0x01);
AG_ButtonNewFlag32(parent, 0, "Bit 2", &MyFlags, 0x02);

The following code fragment uses a button to control an int protected by a mutex device:

int MyInt = 0;
AG_Mutex MyMutex;
AG_Button *btn;

AG_MutexInit(&MyMutex);
btn = AG_ButtonNew(parent, 0, "Mutex-protected flag");
AG_BindIntMp(btn, "state", &MyInt, &MyMutex);

SEE ALSO

HISTORY