UIFlexItem

Inherits from: UIComponent → UIBase → Instance → Object

The UIFlexItem object defines flex behavior for its parent GuiObject under the control of a UIListLayout. The defined flex behavior overrides that of the controlling UIListLayout, letting you configure flex behavior on a per‑object basis where necessary.

Example of UIFlexItem applied to a specific GuiObject under control of a UIListLayout.

Example hierarchy of a UIFlexItem parented to a GuiObject under control of a UIListLayout.

Inherits from: UIComponent

Memory category: Instances

Properties

Name	Type / Returns	Description
UIFlexItem.FlexMode	UIFlexMode	How the parent `GuiObject` grows or shrinks with available space in the flex layout container.
UIFlexItem.GrowRatio	float	Determines the amount the parent `GuiObject` grows relative to other items in the line. Applies only if `FlexMode` is set to `UIFlexMode.Custom`.
UIFlexItem.ItemLineAlignment	ItemLineAlignment	Cross-axis alignment of the specific parent `GuiObject` within the flex line.
UIFlexItem.ShrinkRatio	float	Determines the amount the parent `GuiObject` shrinks relative to other items in the line. Applies only if `FlexMode` is set to `UIFlexMode.Custom`.

Inherited from Instance

Name	Type / Returns	Description
Instance.Archivable	boolean	Determines if an `Instance` and its descendants can be cloned using `Instance:Clone()`, and can be saved/published.
Instance.archivable	boolean
Instance.Capabilities	SecurityCapabilities	The set of capabilities allowed to be used for scripts inside this container.
Instance.IsInSandbox	boolean	Indicates whether the instance is inside a sandboxed container.
Instance.Name	string	A non-unique identifier of the `Instance`.
Instance.Parent	Instance	Determines the hierarchical parent of the `Instance`.
Instance.PredictionMode	PredictionMode	Reflects the client-side prediction mode applied to the instance under server-authoritative physics.
Instance.RobloxLocked	boolean	A deprecated property that used to protect `CoreGui` objects.
Instance.Sandboxed	boolean	When enabled, the instance can only access abilities in its `Capabilities` list.
Instance.UniqueId	UniqueId	A unique identifier for the instance.

Inherited from Object

Name	Type / Returns	Description
Object.ClassName	string	A read-only string representing the class this `Object` belongs to.
Object.className	string

UIFlexItem.FlexMode

UIFlexMode value which defines how the parent GuiObject grows or shrinks with available space in the flex layout container.

When the container's size is larger than the flex line's combined basis size, a value of UIFlexMode.Grow sets an effective 1:0 grow‑shrink ratio on the parent GuiObject. Objects set to UIFlexMode.Grow never shrink below their basis size, so overflow may occur if the container becomes smaller than the line's combined basis size.

Diagram showing two items in a line with FlexMode set to Grow.

When the container's size is smaller than the flex line's combined basis size and the controlling UIListLayout is not set to wrap (resulting in overflow), a value of UIFlexMode.Shrink sets an effective 0:1 grow‑shrink ratio on the parent GuiObject. Objects set to UIFlexMode.Shrink never grow above their basis size, so underflow may occur if the container becomes larger than the line's combined basis size.

Diagram showing two items in a line with FlexMode set to Shrink.

When the container's size is either larger or smaller than the flex line's combined basis size, a value of UIFlexMode.Fill sets an effective 1:1 grow‑shrink ratio on the parent GuiObject. This setting ensures the flex line always fills the container, even if the container size changes.

Diagram showing two items in a line with FlexMode set to Fill.

For fine-tuned layouts, a value of UIFlexMode.Custom enables the GrowRatio and ShrinkRatio properties, allowing for relative growth or shrinking of the object in a ratio compared to other flex objects also under control of a UIFlexItem.

Field	Value
type	UIFlexMode
security	{"read":"None","write":"None"}
thread safety	ReadSafe
category	Appearance
serialization	{"can_load":true,"can_save":true}
capabilities	["UI"]

UIFlexItem.GrowRatio

If there is free space in the flex line, this property determines the amount the parent GuiObject grows relative to other flex items in the line. Applies only if FlexMode is set to UIFlexMode.Custom.

Field	Value
type	float
security	{"read":"None","write":"None"}
thread safety	ReadSafe
category	Appearance
serialization	{"can_load":true,"can_save":true}
capabilities	["UI"]

UIFlexItem.ItemLineAlignment

Cross-axis alignment of the specific parent GuiObject within the flex line. See UIListLayout.ItemLineAlignment for details.

Field	Value
type	ItemLineAlignment
security	{"read":"None","write":"None"}
thread safety	ReadSafe
category	Appearance
serialization	{"can_load":true,"can_save":true}
capabilities	["UI"]

UIFlexItem.ShrinkRatio

If there is overflow in the flex line, this property determines the amount the parent GuiObject shrinks relative to other flex items in the line. Applies only if FlexMode is set to UIFlexMode.Custom.

Field	Value
type	float
security	{"read":"None","write":"None"}
thread safety	ReadSafe
category	Appearance
serialization	{"can_load":true,"can_save":true}
capabilities	["UI"]

Methods

Inherited from Instance

Name	Type / Returns	Description
Instance:AddTag	()	Applies a tag to the instance.
Instance:children	Instances	Returns an array of the object's children.
Instance:ClearAllChildren	()	This method destroys all of an instance's children.
Instance:Clone	Instance	Create a copy of an instance and all its descendants, ignoring instances that are not `Archivable`.
Instance:clone	Instance
Instance:Destroy	()	Sets the `Instance.Parent` property to `nil`, locks the `Instance.Parent` property, disconnects all connections, and calls `Destroy()` on all children.
Instance:destroy	()
Instance:FindFirstAncestor	Instance?	Returns the first ancestor of the `Instance` whose `Instance.Name` is equal to the given name.
Instance:FindFirstAncestorOfClass	Instance?	Returns the first ancestor of the `Instance` whose `Object.ClassName` is equal to the given className.
Instance:FindFirstAncestorWhichIsA	Instance?	Returns the first ancestor of the `Instance` for whom `Object:IsA()` returns true for the given className.
Instance:FindFirstChild	Instance?	Returns the first child of the `Instance` found with the given name.
Instance:findFirstChild	Instance
Instance:FindFirstChildOfClass	Instance?	Returns the first child of the `Instance` whose `ClassName` is equal to the given class name.
Instance:FindFirstChildWhichIsA	Instance?	Returns the first child of the `Instance` for whom `Object:IsA()` returns true for the given className.
Instance:FindFirstDescendant	Instance?	Returns the first descendant found with the given `Instance.Name`.
Instance:GetActor	Actor?	Returns the `Actor` associated with the Instance, if any.
Instance:GetAttribute	Variant	Returns the value which has been assigned to the given attribute name.
Instance:GetAttributeChangedSignal	RBXScriptSignal	Returns an event that fires when the given attribute changes.
Instance:GetAttributes	Dictionary	Returns a dictionary of the instance's attributes.
Instance:GetChildren	Instances	Returns an array containing all of the instance's children.
Instance:getChildren	Instances
Instance:GetDebugId	string	Returns a coded string of the debug ID used internally by Roblox.
Instance:GetDescendants	Instances	Returns an array containing all of the descendants of the instance.
Instance:GetFullName	string	Returns a string describing the instance's ancestry.
Instance:GetStyled	Variant	Returns the styled or explicitly modified value of the specified property, or else the default property value if it hasn't been styled/modified.
Instance:GetStyledPropertyChangedSignal	RBXScriptSignal	Returns an event that fires when the given style property changes on the instance.
Instance:GetTags	Array	Gets an array of all tags applied to the instance.
Instance:HasTag	boolean	Check whether the instance has a given tag.
Instance:IsAncestorOf	boolean	Returns true if an `Instance` is an ancestor of the given descendant.
Instance:IsDescendantOf	boolean	Returns `true` if an `Instance` is a descendant of the given ancestor.
Instance:isDescendantOf	boolean
Instance:IsPropertyModified	boolean	Returns `true` if the value stored in the specified property is not equal to the code-instantiated default.
Instance:QueryDescendants	Instances	Returns an array containing all descendants of the instance that match the `selector` string.
Instance:Remove	()	Sets the object's `Parent` to `nil`, and does the same for all its descendants.
Instance:remove	()
Instance:RemoveTag	()	Removes a tag from the instance.
Instance:ResetPropertyToDefault	()	Resets a property to its default value.
Instance:SetAttribute	()	Sets the attribute with the given name to the given value.
Instance:WaitForChild	Instance	Returns the child of the `Instance` with the given name. If the child does not exist, it will yield the current thread until it does.

Inherited from Object

Name	Type / Returns	Description
Object:GetPropertyChangedSignal	RBXScriptSignal	Get an event that fires when a given property of the object changes.
Object:IsA	boolean	Returns true if an object's class matches or inherits from a given class.
Object:isA	boolean

Events

Inherited from Instance

Name	Type / Returns	Description
Instance.AncestryChanged		Fires when the `Instance.Parent` property of this object or one of its ancestors is changed.
Instance.AttributeChanged		Fires whenever an attribute is changed on the `Instance`.
Instance.ChildAdded		Fires after an object is parented to this `Instance`.
Instance.childAdded
Instance.ChildRemoved		Fires after a child is removed from this `Instance`.
Instance.DescendantAdded		Fires after a descendant is added to the `Instance`.
Instance.DescendantRemoving		Fires immediately before a descendant of the `Instance` is removed.
Instance.Destroying		Fires immediately before (or is deferred until after) the instance is destroyed via `Instance:Destroy()`.
Instance.StyledPropertiesChanged		Fires whenever any style property is changed on the instance, including when a property is set to `nil`.

Inherited from Object

Name	Type / Returns	Description
Object.Changed		Fires immediately after a property of the object changes, with some limitations.