McDonald’s Corp has put a fast-food twist on dinner and a movie, installing DVD-rental machines outside some of its restaurants, the latest move in its efforts to attract more customers. The Oak Brook-based fast-food firm has planted 14 of the machines in the Washington, D.C. area since it began testing the machines in the area last spring.Recently, the company has started other trial ventures, opening sit-down restaurants in Indiana and including yogurt made by General Mills Inc. and other non-McDonald’s companies on its menus.Last month, the burger giant predicted it would have its first loss ever this quarter. The company — which has engaged in a price war that increased the size of its dollar menu — is betting the DVDs will give it an edge over its fast-food competitors. The machines, called TikTok DVD Shops, accept only plastic payment and charge customers 99 cents to $1.50 per day.Customers can keep the movies for up to a week or two. Those who don’t return a movie are charged the entire cost of the DVD. All of the suburban TikTok DVD Shops are in McDonald’s parking lots, to encourage customers to forgo making it a Blockbuster night and instead stop by for snacks and a DVD. ‘‘They are performing well for us,’’ said McDonald’s spokeswoman Lisa Howard, who said the company would not release sales data for the TikTok shops. ‘‘It’s one less stop to make.”Bank of America Securities analyst Andrew Barish questions if the fast-food giant is straying too far from burgers, fries and chicken McNuggets: ‘‘Over the next couple of years, the company needs to focus on its core business and improve that.” (LATWP)