Rect  |  API reference  |  Android Developers (original) (raw)

class Rect : Parcelable

Rect holds four integer coordinates for a rectangle. The rectangle is represented by the coordinates of its 4 edges (left, top, right bottom). These fields can be accessed directly. Use width() and height() to retrieve the rectangle's width and height. Note: most methods do not check to see that the coordinates are sorted correctly (i.e. left <= right and top <= bottom).

Note that the right and bottom coordinates are exclusive. This means a Rect being drawn untransformed onto a [android.graphics.Canvas](/reference/kotlin/android/graphics/Canvas) will draw into the column and row described by its left and top coordinates, but not those of its bottom and right.

Summary

Public constructors

Rect

Rect()

Create a new empty Rect. All coordinates are initialized to 0.

Rect

Rect(r: Rect?)

Create a new rectangle, initialized with the values in the specified rectangle (which is left unmodified).

Rect

Rect(
    left: Int,
    top: Int,
    right: Int,
    bottom: Int)

Create a new rectangle with the specified coordinates. Note: no range checking is performed, so the caller must ensure that left <= right and top <= bottom.

Public methods

centerX

fun centerX(): Int

centerY

fun centerY(): Int

contains

fun contains(r: Rect): Boolean

Returns true iff the specified rectangle r is inside or equal to this rectangle. An empty rectangle never contains another rectangle.

contains

fun contains(
    x: Int,
    y: Int
): Boolean

Returns true if (x,y) is inside the rectangle. The left and top are considered to be inside, while the right and bottom are not. This means that for a x,y to be contained: left <= x < right and top <= y < bottom. An empty rectangle never contains any point.

contains

fun contains(
    left: Int,
    top: Int,
    right: Int,
    bottom: Int
): Boolean

Returns true iff the 4 specified sides of a rectangle are inside or equal to this rectangle. i.e. is this rectangle a superset of the specified rectangle. An empty rectangle never contains another rectangle.

equals

fun equals(other: Any?): Boolean

exactCenterX

fun exactCenterX(): Float

exactCenterY

fun exactCenterY(): Float

flattenToString

fun flattenToString(): String

Return a string representation of the rectangle in a well-defined format.

You can later recover the Rect from this string through [unflattenFromString(java.lang.String)](#unflattenFromString%28kotlin.String%29).

hashCode

fun hashCode(): Int

height

fun height(): Int

inset

fun inset(insets: Insets): Unit

Insets the rectangle on all sides specified by the dimensions of insets.

inset

fun inset(
    dx: Int,
    dy: Int
): Unit

Inset the rectangle by (dx,dy). If dx is positive, then the sides are moved inwards, making the rectangle narrower. If dx is negative, then the sides are moved outwards, making the rectangle wider. The same holds true for dy and the top and bottom.

inset

fun inset(
    left: Int,
    top: Int,
    right: Int,
    bottom: Int
): Unit

Insets the rectangle on all sides specified by the insets.

intersect

fun intersect(r: Rect): Boolean

If the specified rectangle intersects this rectangle, return true and set this rectangle to that intersection, otherwise return false and do not change this rectangle. No check is performed to see if either rectangle is empty. To just test for intersection, use intersects()

intersect

fun intersect(
    left: Int,
    top: Int,
    right: Int,
    bottom: Int
): Boolean

If the rectangle specified by left,top,right,bottom intersects this rectangle, return true and set this rectangle to that intersection, otherwise return false and do not change this rectangle. No check is performed to see if either rectangle is empty. Note: To just test for intersection, use [intersects(android.graphics.Rect,android.graphics.Rect)](#intersects%28android.graphics.Rect,%20android.graphics.Rect%29).

intersects

fun intersects(
    left: Int,
    top: Int,
    right: Int,
    bottom: Int
): Boolean

Returns true if this rectangle intersects the specified rectangle. In no event is this rectangle modified. No check is performed to see if either rectangle is empty. To record the intersection, use intersect() or setIntersect().

intersects

static fun intersects(
    a: Rect,
    b: Rect
): Boolean

Returns true iff the two specified rectangles intersect. In no event are either of the rectangles modified. To record the intersection, use [intersect(android.graphics.Rect)](#intersect%28android.graphics.Rect%29) or [setIntersect(android.graphics.Rect,android.graphics.Rect)](#setIntersect%28android.graphics.Rect,%20android.graphics.Rect%29).

isEmpty

fun isEmpty(): Boolean

Returns true if the rectangle is empty (left >= right or top >= bottom)

offset

fun offset(
    dx: Int,
    dy: Int
): Unit

Offset the rectangle by adding dx to its left and right coordinates, and adding dy to its top and bottom coordinates.

offsetTo

fun offsetTo(
    newLeft: Int,
    newTop: Int
): Unit

Offset the rectangle to a specific (left, top) position, keeping its width and height the same.

readFromParcel

fun readFromParcel(in: Parcel): Unit

Set the rectangle's coordinates from the data stored in the specified parcel. To write a rectangle to a parcel, call writeToParcel().

set

fun set(src: Rect): Unit

Copy the coordinates from src into this rectangle.

set

fun set(
    left: Int,
    top: Int,
    right: Int,
    bottom: Int
): Unit

Set the rectangle's coordinates to the specified values. Note: no range checking is performed, so it is up to the caller to ensure that left <= right and top <= bottom.

setEmpty

fun setEmpty(): Unit

Set the rectangle to (0,0,0,0)

setIntersect

fun setIntersect(
    a: Rect,
    b: Rect
): Boolean

If rectangles a and b intersect, return true and set this rectangle to that intersection, otherwise return false and do not change this rectangle. No check is performed to see if either rectangle is empty. To just test for intersection, use intersects()

sort

fun sort(): Unit

Swap top/bottom or left/right if there are flipped (i.e. left > right and/or top > bottom). This can be called if the edges are computed separately, and may have crossed over each other. If the edges are already correct (i.e. left <= right and top <= bottom) then nothing is done.

toShortString

fun toShortString(): String

Return a string representation of the rectangle in a compact form.

toString

fun toString(): String

unflattenFromString

static fun unflattenFromString(str: String?): Rect?

Returns a Rect from a string of the form returned by [flattenToString](#flattenToString%28%29), or null if the string is not of that form.

union

fun union(r: Rect): Unit

Update this Rect to enclose itself and the specified rectangle. If the specified rectangle is empty, nothing is done. If this rectangle is empty it is set to the specified rectangle.

union

fun union(
    x: Int,
    y: Int
): Unit

Update this Rect to enclose itself and the [x,y] coordinate. There is no check to see that this rectangle is non-empty.

union

fun union(
    left: Int,
    top: Int,
    right: Int,
    bottom: Int
): Unit

Update this Rect to enclose itself and the specified rectangle. If the specified rectangle is empty, nothing is done. If this rectangle is empty it is set to the specified rectangle.

width

fun width(): Int

writeToParcel

fun writeToParcel(
    out: Parcel,
    flags: Int
): Unit

Write this rectangle to the specified parcel. To restore a rectangle from a parcel, use readFromParcel()

Properties