/* ============================================================================== This file is part of the JUCE library. Copyright (c) 2020 - Raw Material Software Limited JUCE is an open source library subject to commercial or open-source licensing. By using JUCE, you agree to the terms of both the JUCE 6 End-User License Agreement and JUCE Privacy Policy (both effective as of the 16th June 2020). End User License Agreement: www.juce.com/juce-6-licence Privacy Policy: www.juce.com/juce-privacy-policy Or: You may also use this code under the terms of the GPL v3 (see www.gnu.org/licenses). JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE DISCLAIMED. ============================================================================== */ namespace juce { //============================================================================== /** For laying out a set of components, where the components have preferred sizes and size limits, but where they are allowed to stretch to fill the available space. For example, if you have a component containing several other components, and each one should be given a share of the total size, you could use one of these to resize the child components when the parent component is resized. Then you could add a StretchableLayoutResizerBar to easily let the user rescale them. A StretchableLayoutManager operates only in one dimension, so if you have a set of components stacked vertically on top of each other, you'd use one to manage their heights. To build up complex arrangements of components, e.g. for applications with multiple nested panels, you would use more than one StretchableLayoutManager. E.g. by using two (one vertical, one horizontal), you could create a resizable spreadsheet-style table. E.g. @code class MyComp : public Component { StretchableLayoutManager myLayout; MyComp() { myLayout.setItemLayout (0, // for item 0 50, 100, // must be between 50 and 100 pixels in size -0.6); // and its preferred size is 60% of the total available space myLayout.setItemLayout (1, // for item 1 -0.2, -0.6, // size must be between 20% and 60% of the available space 50); // and its preferred size is 50 pixels } void resized() { // make a list of two of our child components that we want to reposition Component* comps[] = { myComp1, myComp2 }; // this will position the 2 components, one above the other, to fit // vertically into the rectangle provided. myLayout.layOutComponents (comps, 2, 0, 0, getWidth(), getHeight(), true); } }; @endcode @see StretchableLayoutResizerBar @tags{GUI} */ class JUCE_API StretchableLayoutManager { public: //============================================================================== /** Creates an empty layout. You'll need to add some item properties to the layout before it can be used to resize things - see setItemLayout(). */ StretchableLayoutManager(); /** Destructor. */ ~StretchableLayoutManager(); //============================================================================== /** For a numbered item, this sets its size limits and preferred size. @param itemIndex the index of the item to change. @param minimumSize the minimum size that this item is allowed to be - a positive number indicates an absolute size in pixels. A negative number indicates a proportion of the available space (e.g -0.5 is 50%) @param maximumSize the maximum size that this item is allowed to be - a positive number indicates an absolute size in pixels. A negative number indicates a proportion of the available space @param preferredSize the size that this item would like to be, if there's enough room. A positive number indicates an absolute size in pixels. A negative number indicates a proportion of the available space @see getItemLayout */ void setItemLayout (int itemIndex, double minimumSize, double maximumSize, double preferredSize); /** For a numbered item, this returns its size limits and preferred size. @param itemIndex the index of the item. @param minimumSize the minimum size that this item is allowed to be - a positive number indicates an absolute size in pixels. A negative number indicates a proportion of the available space (e.g -0.5 is 50%) @param maximumSize the maximum size that this item is allowed to be - a positive number indicates an absolute size in pixels. A negative number indicates a proportion of the available space @param preferredSize the size that this item would like to be, if there's enough room. A positive number indicates an absolute size in pixels. A negative number indicates a proportion of the available space @returns false if the item's properties hadn't been set @see setItemLayout */ bool getItemLayout (int itemIndex, double& minimumSize, double& maximumSize, double& preferredSize) const; /** Clears all the properties that have been set with setItemLayout() and resets this object to its initial state. */ void clearAllItems(); //============================================================================== /** Takes a set of components that correspond to the layout's items, and positions them to fill a space. This will try to give each item its preferred size, whether that's a relative size or an absolute one. @param components an array of components that correspond to each of the numbered items that the StretchableLayoutManager object has been told about with setItemLayout() @param numComponents the number of components in the array that is passed-in. This should be the same as the number of items this object has been told about. @param x the left of the rectangle in which the components should be laid out @param y the top of the rectangle in which the components should be laid out @param width the width of the rectangle in which the components should be laid out @param height the height of the rectangle in which the components should be laid out @param vertically if true, the components will be positioned in a vertical stack, so that they fill the height of the rectangle. If false, they will be placed side-by-side in a horizontal line, filling the available width @param resizeOtherDimension if true, this means that the components will have their other dimension resized to fit the space - i.e. if the 'vertically' parameter is true, their x-positions and widths are adjusted to fit the x and width parameters; if 'vertically' is false, their y-positions and heights are adjusted to fit the y and height parameters. */ void layOutComponents (Component** components, int numComponents, int x, int y, int width, int height, bool vertically, bool resizeOtherDimension); //============================================================================== /** Returns the current position of one of the items. This is only a valid call after layOutComponents() has been called, as it returns the last position that this item was placed at. If the layout was vertical, the value returned will be the y position of the top of the item, relative to the top of the rectangle in which the items were placed (so for example, item 0 will always have position of 0, even in the rectangle passed in to layOutComponents() wasn't at y = 0). If the layout was done horizontally, the position returned is the item's left-hand position, again relative to the x position of the rectangle used. @see getItemCurrentSize, setItemPosition */ int getItemCurrentPosition (int itemIndex) const; /** Returns the current size of one of the items. This is only meaningful after layOutComponents() has been called, as it returns the last size that this item was given. If the layout was done vertically, it'll return the item's height in pixels; if it was horizontal, it'll return its width. @see getItemCurrentRelativeSize */ int getItemCurrentAbsoluteSize (int itemIndex) const; /** Returns the current size of one of the items. This is only meaningful after layOutComponents() has been called, as it returns the last size that this item was given. If the layout was done vertically, it'll return a negative value representing the item's height relative to the last size used for laying the components out; if the layout was done horizontally it'll be the proportion of its width. @see getItemCurrentAbsoluteSize */ double getItemCurrentRelativeSize (int itemIndex) const; //============================================================================== /** Moves one of the items, shifting along any other items as necessary in order to get it to the desired position. Calling this method will also update the preferred sizes of the items it shuffles along, so that they reflect their new positions. (This is the method that a StretchableLayoutResizerBar uses to shift the items about when it's dragged). @param itemIndex the item to move @param newPosition the absolute position that you'd like this item to move to. The item might not be able to always reach exactly this position, because other items may have minimum sizes that constrain how far it can go */ void setItemPosition (int itemIndex, int newPosition); private: //============================================================================== struct ItemLayoutProperties { int itemIndex; int currentSize; double minSize, maxSize, preferredSize; }; OwnedArray items; int totalSize = 0; //============================================================================== static int sizeToRealSize (double size, int totalSpace); ItemLayoutProperties* getInfoFor (int itemIndex) const; void setTotalSize (int newTotalSize); int fitComponentsIntoSpace (int startIndex, int endIndex, int availableSpace, int startPos); int getMinimumSizeOfItems (int startIndex, int endIndex) const; int getMaximumSizeOfItems (int startIndex, int endIndex) const; void updatePrefSizesToMatchCurrentPositions(); JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (StretchableLayoutManager) }; } // namespace juce