- Qt 5.15
- Qt GUI
- C++ Classes
- QStyleHints
- Qt 5.15.19 Reference Documentation

# QStyleHints Class

The QStyleHints class contains platform specific hints and settings. More...

Header: | #include <QStyleHints>
qmake: | QT += gui
Since: | Qt 5.0

This class was introduced in Qt 5.0.

- List of all members, including inherited members

## Properties

- cursorFlashTime : const int
- fontSmoothingGamma : const qreal
- keyboardAutoRepeatRate : const int
- keyboardInputInterval : const int
- mouseDoubleClickDistance : const int
- mouseDoubleClickInterval : const int
- mousePressAndHoldInterval : const int
- mouseQuickSelectionThreshold : const int
- passwordMaskCharacter : const QChar
- passwordMaskDelay : const int
- setFocusOnTouchRelease : const bool
- showIsFullScreen : const bool

- showIsMaximized : const bool
- showShortcutsInContextMenus : bool
- singleClickActivation : const bool
- startDragDistance : const int
- startDragTime : const int
- startDragVelocity : const int
- tabFocusBehavior : const Qt::TabFocusBehavior
- touchDoubleTapDistance : const int
- useHoverEffects : bool
- useRtlExtensions : const bool
- wheelScrollLines : const int

## Public Functions

int | cursorFlashTime() const
qreal | fontSmoothingGamma() const
int | keyboardAutoRepeatRate() const
int | keyboardInputInterval() const
int | mouseDoubleClickDistance() const
int | mouseDoubleClickInterval() const
int | mousePressAndHoldInterval() const
int | mouseQuickSelectionThreshold() const
QChar | passwordMaskCharacter() const
int | passwordMaskDelay() const
bool | setFocusOnTouchRelease() const
void | setShowShortcutsInContextMenus(bool showShortcutsInContextMenus)
void | setUseHoverEffects(bool useHoverEffects)
bool | showIsFullScreen() const
bool | showIsMaximized() const
bool | showShortcutsInContextMenus() const
bool | singleClickActivation() const
int | startDragDistance() const
int | startDragTime() const
int | startDragVelocity() const
Qt::TabFocusBehavior | tabFocusBehavior() const
int | touchDoubleTapDistance() const
bool | useHoverEffects() const
bool | useRtlExtensions() const
int | wheelScrollLines() const

## Signals

void | cursorFlashTimeChanged(int cursorFlashTime)
void | keyboardInputIntervalChanged(int keyboardInputInterval)
void | mouseDoubleClickIntervalChanged(int mouseDoubleClickInterval)
void | mousePressAndHoldIntervalChanged(int mousePressAndHoldInterval)
void | mouseQuickSelectionThresholdChanged(int threshold)
void | showShortcutsInContextMenusChanged(bool)
void | startDragDistanceChanged(int startDragDistance)
void | startDragTimeChanged(int startDragTime)
void | tabFocusBehaviorChanged(Qt::TabFocusBehavior tabFocusBehavior)
void | useHoverEffectsChanged(bool useHoverEffects)
void | wheelScrollLinesChanged(int scrollLines)

## Detailed Description

An object of this class, obtained from QGuiApplication, provides access to certain global user interface parameters of the current platform.

Access is read only; typically the platform itself provides the user a way to tune these parameters.

Access to these parameters are useful when implementing custom user interface components, in that they allow the components to exhibit the same behaviour and feel as other components.

See also QGuiApplication::styleHints().

## Property Documentation

### cursorFlashTime : const int

This property holds the text cursor's flash (blink) time in milliseconds.

The flash time is the time used to display, invert and restore the caret display. Usually the text cursor is displayed for half the cursor flash time, then hidden for the same amount of time.

Access functions:

int | cursorFlashTime() const

Notifier signal:

void | cursorFlashTimeChanged(int cursorFlashTime)

### fontSmoothingGamma : const qreal

This property holds the gamma value used in font smoothing.

Access functions:

qreal | fontSmoothingGamma() const

### keyboardAutoRepeatRate : const int

This property holds the rate, in events per second, in which additional repeated key presses will automatically be generated if a key is being held down.

Access functions:

int | keyboardAutoRepeatRate() const

### keyboardInputInterval : const int

This property holds the time limit, in milliseconds, that distinguishes a key press from two consecutive key presses.

Access functions:

int | keyboardInputInterval() const

Notifier signal:

void | keyboardInputIntervalChanged(int keyboardInputInterval)

### mouseDoubleClickDistance : const int

This property holds the maximum distance, in pixels, that the mouse can be moved between two consecutive mouse clicks and still have it detected as a double-click

This property was introduced in Qt 5.14.

Access functions:

int | mouseDoubleClickDistance() const

### mouseDoubleClickInterval : const int

This property holds the time limit in milliseconds that distinguishes a double click from two consecutive mouse clicks.

Access functions:

int | mouseDoubleClickInterval() const

Notifier signal:

void | mouseDoubleClickIntervalChanged(int mouseDoubleClickInterval)

### mousePressAndHoldInterval : const int

This property holds the time limit in milliseconds that activates a press and hold.

This property was introduced in Qt 5.3.

Access functions:

int | mousePressAndHoldInterval() const

Notifier signal:

void | mousePressAndHoldIntervalChanged(int mousePressAndHoldInterval)

### mouseQuickSelectionThreshold : const int

Quick selection mouse threshold in QLineEdit.

This property defines how much the mouse cursor should be moved along the y axis to trigger a quick selection during a normal QLineEdit text selection.

If the property value is less than or equal to 0, the quick selection feature is disabled.

This property was introduced in Qt 5.11.

Access functions:

int | mouseQuickSelectionThreshold() const

Notifier signal:

void | mouseQuickSelectionThresholdChanged(int threshold)

### passwordMaskCharacter : const QChar

This property holds the character used to mask the characters typed into text input fields in password mode.

Access functions:

QChar | passwordMaskCharacter() const

### passwordMaskDelay : const int

This property holds the time, in milliseconds, a typed letter is displayed unshrouded in a text input field in password mode.

Access functions:

int | passwordMaskDelay() const

### setFocusOnTouchRelease : const bool

This property holds the event that should set input focus on focus objects.

This property is `true` if focus objects (line edits etc) should receive input focus after a touch/mouse release. This is normal behavior on touch platforms. On desktop platforms, the standard is to set focus already on touch/mouse press.

Access functions:

bool | setFocusOnTouchRelease() const

### showIsFullScreen : const bool

This property holds whether the platform defaults to fullscreen windows.

This property is `true` if the platform defaults to windows being fullscreen, otherwise `false`.

Note: The platform may still choose to show certain windows non-fullscreen, such as popups or dialogs. This property only reports the default behavior.

Access functions:

bool | showIsFullScreen() const

See also QWindow::show() and showIsMaximized().

### showIsMaximized : const bool

This property holds whether the platform defaults to maximized windows.

This property is `true` if the platform defaults to windows being maximized, otherwise `false`.

Note: The platform may still choose to show certain windows non-maximized, such as popups or dialogs. This property only reports the default behavior.

This property was introduced in Qt 5.6.

Access functions:

bool | showIsMaximized() const

See also QWindow::show() and showIsFullScreen().

### showShortcutsInContextMenus : bool

`true` if the platform normally shows shortcut key sequences in context menus, otherwise `false`.

Since Qt 5.13, the setShowShortcutsInContextMenus() function can be used to override the platform default.

This property was introduced in Qt 5.10.

Access functions:

bool | showShortcutsInContextMenus() const
void | setShowShortcutsInContextMenus(bool showShortcutsInContextMenus)

Notifier signal:

void | showShortcutsInContextMenusChanged(bool)

### singleClickActivation : const bool

This property holds whether items are activated by single or double click.

This property is `true` if items should be activated by single click, `false` if they should be activated by double click instead.

This property was introduced in Qt 5.5.

Access functions:

bool | singleClickActivation() const

### startDragDistance : const int

This property holds the distance, in pixels, that the mouse must be moved with a button held down before a drag and drop operation will begin.

If you support drag and drop in your application, and want to start a drag and drop operation after the user has moved the cursor a certain distance with a button held down, you should use this property's value as the minimum distance required.

For example, if the mouse position of the click is stored in `startPos` and the current position (e.g. in the mouse move event) is `currentPos`, you can find out if a drag should be started with code like this:

     if ((startPos - currentPos).manhattanLength() >=
             QApplication::startDragDistance())
         startTheDrag();

Access functions:

int | startDragDistance() const

Notifier signal:

void | startDragDistanceChanged(int startDragDistance)

See also startDragTime, QPoint::manhattanLength(), and Drag and Drop.

### startDragTime : const int

This property holds the time, in milliseconds, that a mouse button must be held down before a drag and drop operation will begin.

If you support drag and drop in your application, and want to start a drag and drop operation after the user has held down a mouse button for a certain amount of time, you should use this property's value as the delay.

Access functions:

int | startDragTime() const

Notifier signal:

void | startDragTimeChanged(int startDragTime)

See also startDragDistance and Drag and Drop.

### startDragVelocity : const int

This property holds the limit for the velocity, in pixels per second, that the mouse may be moved, with a button held down, for a drag and drop operation to begin. A value of 0 means there is no such limit.

Access functions:

int | startDragVelocity() const

See also startDragDistance and Drag and Drop.

### tabFocusBehavior : const Qt::TabFocusBehavior

This property holds the focus behavior on press of the tab key.

Note: Do not bind this value in QML because the change notifier signal is not implemented yet.

This property was introduced in Qt 5.5.

Access functions:

Qt::TabFocusBehavior | tabFocusBehavior() const

Notifier signal:

void | tabFocusBehaviorChanged(Qt::TabFocusBehavior tabFocusBehavior)

### touchDoubleTapDistance : const int

This property holds the maximum distance, in pixels, that a finger can be moved between two consecutive taps and still have it detected as a double-tap

This property was introduced in Qt 5.14.

Access functions:

int | touchDoubleTapDistance() const

### useHoverEffects : bool

This property holds whether UI elements use hover effects.

This property is `true` if UI elements should use hover effects. This is the standard behavior on desktop platforms with a mouse pointer, whereas on touch platforms the overhead of hover event delivery can be avoided.

This property was introduced in Qt 5.8.

Access functions:

bool | useHoverEffects() const
void | setUseHoverEffects(bool useHoverEffects)

Notifier signal:

void | useHoverEffectsChanged(bool useHoverEffects)

### useRtlExtensions : const bool

This property holds the writing direction.

This property is `true` if right-to-left writing direction is enabled, otherwise `false`.

Access functions:

bool | useRtlExtensions() const

### wheelScrollLines : const int

Number of lines to scroll by default for each wheel click.

This property was introduced in Qt 5.9.

Access functions:

int | wheelScrollLines() const

Notifier signal:

void | wheelScrollLinesChanged(int scrollLines)