module gradient_rect; import dguihub; class MainForm : Form { public this() { this.text = "GDI: Gradient Fill Rect"; this.size = Size(400, 200); this.startPosition = FormStartPosition.centerScreen; } protected override void onPaint(PaintEventArgs e) { Canvas c = e.canvas; c.fillRectGradient(Rect(nullPoint, this.size), SystemColors.blue, SystemColors.green, GradientFillRectMode.vertical); super.onPaint(e); } } int main(string[] args) { return Application.run(new MainForm()); // Start the application }