Radio Button

Radio buttons are essential GUI elements that allow users to select one option from a set. They are commonly used in forms and dialogs. Below is the detailed documentation for the GUIRadioButton class.

Constructor

GUIRadioButton(
    int x, int y,
    const char *text,
    int flags
)

Creates a radio button with the specified position, text, and flags.

x: x-coordinate of the radio button’s position.
y: y-coordinate of the radio button’s position.
text: text displayed to the right-hand side of the radio button.
flags: A bitfield of flags specified by bitwise-ORing members of the Flag enum (e.g., FlagSelected, FlagEnabled).

Flags

FlagSelected

FlagSelected = 1 << 2

Causes the radio button to be selected by default.

FlagEnabled

FlagEnabled = 1 << 15

Makes the radio button interactive.

Usage

Let’s create two radio buttons labeled “Option 1” and “Option 2”:

Radio buttons labeled "Option 1" and "Option 2"

// parent is the dialog or parent container

const int radioFlags = GUIRadioButton::FlagEnabled;

GUIRadioButton m_radioButtonOption1 = new GUIRadioButton(
    parent.GetLeftX() + 10,
    parent.GetTopY() + 30,
    "Option 1",
    radioFlags | GUIRadioButton::FlagSelected
);

GUIRadioButton m_radioButtonOption2 = new GUIRadioButton(
    parent.GetLeftX() + 10,
    parent.GetTopY() + 60,
    "Option 2",
    radioFlags
);

const uint16_t RADIO_BUTTON_OPTION1_ID = 1;
const uint16_t RADIO_BUTTON_OPTION2_ID = 2;

// ...

// On the parent.OnEvent, here a GUIDialog:
virtual int OnEvent(struct GUIDialog_Wrapped *dialog, struct GUIDialog_OnEvent_Data *event) {
    uint16_t eventID = event->GetEventID();
    if (eventID == RADIO_BUTTON_OPTION1_ID || eventID == RADIO_BUTTON_OPTION2_ID) {
        // Deselect both radio buttons
        m_radioButtonOption1->SetFlags(m_radioButtonOption1->GetFlags() & ~GUIRadioButton::FlagSelected);
        m_radioButtonOption2->SetFlags(m_radioButtonOption2->GetFlags() & ~GUIRadioButton::FlagSelected);

        // Select the clicked radio button
        if (eventID == RADIO_BUTTON_OPTION1_ID) {
            m_radioButtonOption1->SetFlags(m_radioButtonOption1->GetFlags() | GUIRadioButton::FlagSelected);
        } else if (eventID == RADIO_BUTTON_OPTION2_ID) {
            m_radioButtonOption2->SetFlags(m_radioButtonOption2->GetFlags() | GUIRadioButton::FlagSelected);
        }

        // TODO: handle radio button selection change
        return 0;
    }
    // If we don't process the event, let the base class process it.
    return GUIDialog::OnEvent(dialog, event);
}