FYP(Sem B) Week 9: Building the Marketplace and Trader Page

This was a big week because the marketplace and trader page are basically where all the player interaction happens. Without these pages the game is just a dashboard with numbers going up and down.

For the marketplace we built a card layout where each listing shows the material name, quantity, price per unit, and who is selling it. We added filters so you can sort by price or material type. Each card has a "Buy Now" button for instant purchase and a "Make Offer" button that takes you into negotiation.

The trader page was trickier. We needed a back-and-forth negotiation flow where two players can send counter-offers to each other. We built an offer history log so both sides can see every offer that was made. There are Accept, Reject, and Counter buttons with validation — you cannot offer money you do not have or sell materials that are not in your inventory.

The hardest design decision was the timeout. We did not want negotiations to drag on forever and block the game, so we added a timer per round. We initially set it at 30 seconds which felt reasonable to us at the time. Spoiler — users hated it in testing later, but we will get to that.

When a deal goes through, the stats update — materials transfer, money moves, waste levels change. Seeing a completed trade ripple through the entire city stat system was satisfying.