JUCE  v5.4.1-191-g0ab5e696f
JUCE API
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juce::RelativeCoordinate Class Reference

Expresses a coordinate as a dynamically evaluated expression. More...

#include <juce_RelativeCoordinate.h>

Collaboration diagram for juce::RelativeCoordinate:

Classes

struct  StandardStrings
 
struct  Strings
 A set of static strings that are commonly used by the RelativeCoordinate class. More...
 

Public Member Functions

 RelativeCoordinate ()
 Creates a zero coordinate. More...
 
 RelativeCoordinate (const Expression &expression)
 
 RelativeCoordinate (const RelativeCoordinate &)
 
 RelativeCoordinate (RelativeCoordinate &&) noexcept
 
 RelativeCoordinate (double absoluteDistanceFromOrigin)
 Creates an absolute position from the parent origin on either the X or Y axis. More...
 
 RelativeCoordinate (const String &stringVersion)
 Recreates a coordinate from a string description. More...
 
 ~RelativeCoordinate ()
 Destructor. More...
 
const ExpressiongetExpression () const
 Returns the expression that defines this coordinate. More...
 
bool isDynamic () const
 Returns true if this coordinate depends on any other coordinates for its position. More...
 
bool isRecursive (const Expression::Scope *evaluationScope) const
 Returns true if there's a recursive loop when trying to resolve this coordinate's position. More...
 
void moveToAbsolute (double absoluteTargetPosition, const Expression::Scope *evaluationScope)
 Changes the value of this coord to make it resolve to the specified position. More...
 
bool operator!= (const RelativeCoordinate &) const noexcept
 
RelativeCoordinateoperator= (const RelativeCoordinate &)
 
RelativeCoordinateoperator= (RelativeCoordinate &&) noexcept
 
bool operator== (const RelativeCoordinate &) const noexcept
 
bool references (const String &coordName, const Expression::Scope *evaluationScope) const
 Returns true if this coordinate uses the specified coord name at any level in its evaluation. More...
 
double resolve (const Expression::Scope *evaluationScope) const
 Calculates the absolute position of this coordinate. More...
 
String toString () const
 Returns a string which represents this coordinate. More...
 

Private Attributes

Expression term
 

Detailed Description

Expresses a coordinate as a dynamically evaluated expression.

When using relative coordinates to position components, the following symbols are available:

  • "left", "right", "top", "bottom" refer to the position of those edges in this component, so e.g. for a component whose width is always 100, you might set the right edge to the "left + 100".
  • "[id].left", "[id].right", "[id].top", "[id].bottom", "[id].width", "[id].height", where [id] is the identifier of one of this component's siblings. A component's identifier is set with Component::setComponentID(). So for example if you want your component to always be 50 pixels to the right of the one called "xyz", you could set your left edge to be "xyz.right + 50".
  • Instead of an [id], you can use the name "parent" to refer to this component's parent. Like any other component, these values are relative to their component's parent, so "parent.right" won't be very useful for positioning a component because it refers to a position with the parent's parent.. but "parent.width" can be used for setting positions relative to the parent's size. E.g. to make a 10x10 component which remains 1 pixel away from its parent's bottom-right, you could use "right - 10, bottom - 10, parent.width - 1, parent.height - 1".
  • The name of one of the parent component's markers can also be used as a symbol. For markers to be used, the parent component must implement its Component::getMarkers() method, and return at least one valid MarkerList. So if you want your component's top edge to be 10 pixels below the marker called "foobar", you'd set it to "foobar + 10".

See the Expression class for details about the operators that are supported, but for example if you wanted to make your component remains centred within its parent with a size of 100, 100, you could express it as:

myComp.setBounds (RelativeBounds ("parent.width / 2 - 50, parent.height / 2 - 50, left + 100, top + 100"));

..or an alternative way to achieve the same thing:

myComp.setBounds (RelativeBounds ("right - 100, bottom - 100, parent.width / 2 + 50, parent.height / 2 + 50"));

Or if you wanted a 100x100 component whose top edge is lined up to a marker called "topMarker" and which is positioned 50 pixels to the right of another component called "otherComp", you could write:

myComp.setBounds (RelativeBounds ("otherComp.right + 50, topMarker, left + 100, top + 100"));

Be careful not to make your coordinate expressions recursive, though, or exceptions and assertions will be thrown!

See also
RelativePoint, RelativeRectangle

{GUI}

Constructor & Destructor Documentation

◆ RelativeCoordinate() [1/6]

juce::RelativeCoordinate::RelativeCoordinate ( )

Creates a zero coordinate.

◆ RelativeCoordinate() [2/6]

juce::RelativeCoordinate::RelativeCoordinate ( const Expression expression)

◆ RelativeCoordinate() [3/6]

juce::RelativeCoordinate::RelativeCoordinate ( const RelativeCoordinate )

◆ RelativeCoordinate() [4/6]

juce::RelativeCoordinate::RelativeCoordinate ( RelativeCoordinate &&  )
noexcept

◆ RelativeCoordinate() [5/6]

juce::RelativeCoordinate::RelativeCoordinate ( double  absoluteDistanceFromOrigin)

Creates an absolute position from the parent origin on either the X or Y axis.

Parameters
absoluteDistanceFromOriginthe distance from the origin

◆ RelativeCoordinate() [6/6]

juce::RelativeCoordinate::RelativeCoordinate ( const String stringVersion)

Recreates a coordinate from a string description.

The string will be parsed by ExpressionParser::parse().

Parameters
stringVersionthe expression to use
See also
toString

◆ ~RelativeCoordinate()

juce::RelativeCoordinate::~RelativeCoordinate ( )

Destructor.

Member Function Documentation

◆ getExpression()

const Expression& juce::RelativeCoordinate::getExpression ( ) const
inline

Returns the expression that defines this coordinate.

◆ isDynamic()

bool juce::RelativeCoordinate::isDynamic ( ) const

Returns true if this coordinate depends on any other coordinates for its position.

◆ isRecursive()

bool juce::RelativeCoordinate::isRecursive ( const Expression::Scope evaluationScope) const

Returns true if there's a recursive loop when trying to resolve this coordinate's position.

◆ moveToAbsolute()

void juce::RelativeCoordinate::moveToAbsolute ( double  absoluteTargetPosition,
const Expression::Scope evaluationScope 
)

Changes the value of this coord to make it resolve to the specified position.

Calling this will leave the anchor points unchanged, but will set this coordinate's absolute or relative position to whatever value is necessary to make its resultant position match the position that is provided.

◆ operator!=()

bool juce::RelativeCoordinate::operator!= ( const RelativeCoordinate ) const
noexcept

◆ operator=() [1/2]

RelativeCoordinate& juce::RelativeCoordinate::operator= ( const RelativeCoordinate )

◆ operator=() [2/2]

RelativeCoordinate& juce::RelativeCoordinate::operator= ( RelativeCoordinate &&  )
noexcept

◆ operator==()

bool juce::RelativeCoordinate::operator== ( const RelativeCoordinate ) const
noexcept

◆ references()

bool juce::RelativeCoordinate::references ( const String coordName,
const Expression::Scope evaluationScope 
) const

Returns true if this coordinate uses the specified coord name at any level in its evaluation.

This will recursively check any coordinates upon which this one depends.

◆ resolve()

double juce::RelativeCoordinate::resolve ( const Expression::Scope evaluationScope) const

Calculates the absolute position of this coordinate.

You'll need to provide a suitable Expression::Scope for looking up any coordinates that may be needed to calculate the result.

◆ toString()

String juce::RelativeCoordinate::toString ( ) const

Returns a string which represents this coordinate.

For details of the string syntax, see the constructor notes.

Member Data Documentation

◆ term

Expression juce::RelativeCoordinate::term
private

The documentation for this class was generated from the following file: