I want to build a grid and I have 2 concepts: Grid which is consist of Cell.

Grid class is:

var Grid = function (rows, columns, cellInit) {
    var canvas = create_canvas();
    this.context = canvas.getContext('2d');
    
    this.matrix = new Array(rows);
    for (var x = 0; x < rows; x+=1) {
        this.matrix[x] = new Array(columns);
        for (var y = 0; y < columns; y+=1) {
            this.matrix[x][y] = new Cell(x, y, cellInit(), this.context);
        }
    }
};

Cell class is:

var Cell = function (x, y, value, context) {
    this.x = x;
    this.y = y;
    this.rectX = s.cell_width * this.x + s.pad;
    this.rectY = s.cell_height * this.y + s.pad;
    this.value = value;
    this.context = context;
};

Also I have fill method for Cell:

Cell.prototype.fill = function(type) {
    this.context.fillStyle = s.colors[type];
    this.context.fillRect(this.rectX, this.rectY, s.rect_width, s.rect_height);
    return this;
}

And actually I have 2 questions about this code:

• Looks like that Grid and Cell should have parent-child relationship. Is it normal that I'm creating child objects at parent class?
• I need somehow to give access to context var from Cell class without passing it via constructor. I had tried to play with prototypes but can't figure out how to do that.