很简单的一个类，一个rect放置在另一个rect中如何放置。只是没有考虑边距等，估且认为是在外层作考虑吧。然后认为是外框比内框大，所以外层怕是要进行检查才行
#ifndef JUCE_JUSTIFICATION_H_INCLUDED
#define JUCE_JUSTIFICATION_H_INCLUDED //==============================================================================
/**
Represents a type of justification to be used when positioning graphical items. e.g. it indicates whether something should be placed top-left, top-right,
centred, etc. It is used in various places wherever this kind of information is needed.
*/
class Justification
{
public:
//==============================================================================
/** Creates a Justification object using a combination of flags from the Flags enum. */
Justification (int justificationFlags) noexcept : flags (justificationFlags) {} /** Creates a copy of another Justification object. */
Justification (const Justification& other) noexcept : flags (other.flags) {} /** Copies another Justification object. */
Justification& operator= (const Justification& other) noexcept
{
flags = other.flags;
return *this;
} bool operator== (const Justification& other) const noexcept { return flags == other.flags; }
bool operator!= (const Justification& other) const noexcept { return flags != other.flags; } //==============================================================================
/** Returns the raw flags that are set for this Justification object. */
inline int getFlags() const noexcept { return flags; } /** Tests a set of flags for this object.
@returns true if any of the flags passed in are set on this object.
*/
inline bool testFlags (int flagsToTest) const noexcept { return (flags & flagsToTest) != 0; } /** Returns just the flags from this object that deal with vertical layout. */
int getOnlyVerticalFlags() const noexcept { return flags & (top | bottom | verticallyCentred); } /** Returns just the flags from this object that deal with horizontal layout. */
int getOnlyHorizontalFlags() const noexcept { return flags & (left | right | horizontallyCentred | horizontallyJustified); } //==============================================================================
/** Adjusts the position of a rectangle to fit it into a space. The (x, y) position of the rectangle will be updated to position it inside the
given space according to the justification flags.
*/
template <typename ValueType>
void applyToRectangle (ValueType& x, ValueType& y, ValueType w, ValueType h,
ValueType spaceX, ValueType spaceY, ValueType spaceW, ValueType spaceH) const noexcept
{
x = spaceX;
if ((flags & horizontallyCentred) != 0) x += (spaceW - w) / (ValueType) 2;
else if ((flags & right) != 0) x += spaceW - w; y = spaceY;
if ((flags & verticallyCentred) != 0) y += (spaceH - h) / (ValueType) 2;
else if ((flags & bottom) != 0) y += spaceH - h;
} /** Returns the new position of a rectangle that has been justified to fit within a given space.
*/
template <typename ValueType>
const Rectangle<ValueType> appliedToRectangle (const Rectangle<ValueType>& areaToAdjust,
const Rectangle<ValueType>& targetSpace) const noexcept
{
ValueType x = areaToAdjust.getX(), y = areaToAdjust.getY();
applyToRectangle (x, y, areaToAdjust.getWidth(), areaToAdjust.getHeight(),
targetSpace.getX(), targetSpace.getY(), targetSpace.getWidth(), targetSpace.getHeight());
return areaToAdjust.withPosition (x, y);
} //==============================================================================
/** Flag values that can be combined and used in the constructor. */
enum Flags
{
//==============================================================================
/** Indicates that the item should be aligned against the left edge of the available space. */
left = 1, /** Indicates that the item should be aligned against the right edge of the available space. */
right = 2, /** Indicates that the item should be placed in the centre between the left and right
sides of the available space. */
horizontallyCentred = 4, //==============================================================================
/** Indicates that the item should be aligned against the top edge of the available space. */
top = 8, /** Indicates that the item should be aligned against the bottom edge of the available space. */
bottom = 16, /** Indicates that the item should be placed in the centre between the top and bottom
sides of the available space. */
verticallyCentred = 32, //==============================================================================
/** Indicates that lines of text should be spread out to fill the maximum width
available, so that both margins are aligned vertically.
*/
horizontallyJustified = 64, //==============================================================================
/** Indicates that the item should be centred vertically and horizontally.
This is equivalent to (horizontallyCentred | verticallyCentred)
*/
centred = 36, /** Indicates that the item should be centred vertically but placed on the left hand side.
This is equivalent to (left | verticallyCentred)
*/
centredLeft = 33, /** Indicates that the item should be centred vertically but placed on the right hand side.
This is equivalent to (right | verticallyCentred)
*/
centredRight = 34, /** Indicates that the item should be centred horizontally and placed at the top.
This is equivalent to (horizontallyCentred | top)
*/
centredTop = 12, /** Indicates that the item should be centred horizontally and placed at the bottom.
This is equivalent to (horizontallyCentred | bottom)
*/
centredBottom = 20, /** Indicates that the item should be placed in the top-left corner.
This is equivalent to (left | top)
*/
topLeft = 9, /** Indicates that the item should be placed in the top-right corner.
This is equivalent to (right | top)
*/
topRight = 10, /** Indicates that the item should be placed in the bottom-left corner.
This is equivalent to (left | bottom)
*/
bottomLeft = 17, /** Indicates that the item should be placed in the bottom-left corner.
This is equivalent to (right | bottom)
*/
bottomRight = 18
}; private:
//==============================================================================
int flags;
}; #endif // JUCE_JUSTIFICATION_H_INCLUDED