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LayoutParams

open class LayoutParams : MarginLayoutParams
kotlin.Any
   ↳ android.view.ViewGroup.LayoutParams
   ↳ android.view.ViewGroup.MarginLayoutParams
   ↳ androidx.gridlayout.widget.GridLayout.LayoutParams

Layout information associated with each of the children of a GridLayout.

GridLayout supports both row and column spanning and arbitrary forms of alignment within each cell group. The fundamental parameters associated with each cell group are gathered into their vertical and horizontal components and stored in the rowSpec and columnSpec layout parameters. Specs are immutable structures and may be shared between the layout parameters of different children.

The row and column specs contain the leading and trailing indices along each axis and together specify the four grid indices that delimit the cells of this cell group.

The alignment properties of the row and column specs together specify both aspects of alignment within the cell group. It is also possible to specify a child's alignment within its cell group by using the GridLayout.LayoutParams#setGravity(int) method.

The weight property is also included in Spec and specifies the proportion of any excess space that is due to the associated view.

WRAP_CONTENT and MATCH_PARENT

Because the default values of the width and height properties are both WRAP_CONTENT, this value never needs to be explicitly declared in the layout parameters of GridLayout's children. In addition, GridLayout does not distinguish the special size value MATCH_PARENT from WRAP_CONTENT. A component's ability to expand to the size of the parent is instead controlled by the principle of flexibility, as discussed in GridLayout.

Summary

You should not need to use either of the special size values: WRAP_CONTENT or MATCH_PARENT when configuring the children of a GridLayout.

Default values

See GridLayout for a more complete description of the conventions used by GridLayout in the interpretation of the properties of this class.

Summary

Public constructors

<init>(rowSpec: GridLayout.Spec!, columnSpec: GridLayout.Spec!)

Constructs a new LayoutParams instance for this rowSpec and columnSpec.

Constructs a new LayoutParams with default values as defined in LayoutParams.

<init>(params: LayoutParams!)

Copy constructor.

<init>(context: Context!, attrs: AttributeSet!)

Values not defined in the attribute set take the default values defined in LayoutParams.

Public methods

open Boolean
equals(other: Any?)

open Int

open Unit
setGravity(gravity: Int)

Describes how the child views are positioned.

Protected methods

open Unit
setBaseAttributes(attributes: TypedArray!, widthAttr: Int, heightAttr: Int)

Properties

GridLayout.Spec!

The spec that defines the horizontal characteristics of the cell group described by these layout parameters.

GridLayout.Spec!

The spec that defines the vertical characteristics of the cell group described by these layout parameters.

Public constructors

<init>

LayoutParams(rowSpec: GridLayout.Spec!, columnSpec: GridLayout.Spec!)

Constructs a new LayoutParams instance for this rowSpec and columnSpec. All other fields are initialized with default values as defined in LayoutParams.

Parameters
rowSpec GridLayout.Spec!: the rowSpec
columnSpec GridLayout.Spec!: the columnSpec

<init>

LayoutParams()

Constructs a new LayoutParams with default values as defined in LayoutParams.

<init>

LayoutParams(params: LayoutParams!)

<init>

LayoutParams(params: MarginLayoutParams!)

<init>

LayoutParams(source: GridLayout.LayoutParams!)

Copy constructor. Clones the width, height, margin values, row spec, and column spec of the source.

Parameters
source GridLayout.LayoutParams!: The layout params to copy from.

<init>

LayoutParams(context: Context!, attrs: AttributeSet!)

Values not defined in the attribute set take the default values defined in LayoutParams.

Public methods

equals

open fun equals(other: Any?): Boolean

hashCode

open fun hashCode(): Int

setGravity

open fun setGravity(gravity: Int): Unit

Describes how the child views are positioned. Default is LEFT | BASELINE. See Gravity.

Parameters
gravity Int: the new gravity value

Protected methods

setBaseAttributes

protected open fun setBaseAttributes(attributes: TypedArray!, widthAttr: Int, heightAttr: Int): Unit

Properties

columnSpec

var columnSpec: GridLayout.Spec!

The spec that defines the horizontal characteristics of the cell group described by these layout parameters. If an assignment is made to this field after a measurement or layout operation has already taken place, a call to ViewGroup#setLayoutParams(ViewGroup.LayoutParams) must be made to notify GridLayout of the change. GridLayout is normally able to detect when code fails to observe this rule, issue a warning and take steps to compensate for the omission. This facility is implemented on a best effort basis and should not be relied upon in production code - so it is best to include the above calls to remove the warnings as soon as it is practical.

rowSpec

var rowSpec: GridLayout.Spec!

The spec that defines the vertical characteristics of the cell group described by these layout parameters. If an assignment is made to this field after a measurement or layout operation has already taken place, a call to ViewGroup#setLayoutParams(ViewGroup.LayoutParams) must be made to notify GridLayout of the change. GridLayout is normally able to detect when code fails to observe this rule, issue a warning and take steps to compensate for the omission. This facility is implemented on a best effort basis and should not be relied upon in production code - so it is best to include the above calls to remove the warnings as soon as it is practical.