Grid.cpp

#include "Grid.hpp"
#include "InputEvents.hpp"
 
namespace Chesto {
 
Grid::Grid(int columns, int width, int cellPadding, int rowPadding)
    : columns(columns)
    , width(width)
    , cellPadding(cellPadding)
    , rowPadding(rowPadding)
{
    this->width = width;
    this->height = 0; // calculated on refresh()
}
 
void Grid::refresh()
{
    if (elements.empty()) {
        this->height = 0;
        return;
    }
    
    // calculate cell width: (total width - padding between cells) / columns
    int cellWidth = (this->width - (cellPadding * (columns - 1))) / columns;
    
    int xPos = 0;
    int yPos = 0;
    int currentRowHeight = 0;
    int col = 0;
    
    for (auto& elem : elements) {
        // actually position the element
        elem->x = xPos;
        elem->y = yPos;
        
        // the tallest element in this row
        if (elem->height > currentRowHeight) {
            currentRowHeight = elem->height;
        }
        
        // advance column
        col++;
        xPos += cellWidth + cellPadding;
        
        // do we need to start a new row?
        if (col >= columns) {
            col = 0;
            xPos = 0;
            yPos += currentRowHeight + rowPadding;
            currentRowHeight = 0;
        }
    }
    
    // final grid height
    if (col > 0) {
        yPos += currentRowHeight; // commit last row height
    } else if (yPos > 0) {
        yPos -= rowPadding;
    }
    
    this->height = yPos;
}
 
bool Grid::process(InputEvents* event)
{
    // This method lets the children elements handle their
    // touch events, but manages grid-like cursor navigation    
    bool ret = false;
    
    // normal event handling
    ret |= Element::process(event);
    
    if (elements.empty()) {
        return ret;
    }
    
    if (touchMode) {
        return ret;
    }
    
    // cursor logic from HBAS's AppList
    // int origHighlighted = highlighted;
    
    // start highlight if none
    if (highlighted < 0 && !elements.empty()) {
        highlighted = 0;
    }
    
    // ensure highlighted is in bounds
    if (highlighted >= (int)elements.size()) {
        highlighted = elements.size() - 1;
    }
 
    // TODO: fiinsh grid navigation logic
    ret = true;
    
    return ret;
}
 
} // namespace Chesto