The video shows a man learning the dangers of texting while walking after he tripped on a step and hit his head on an open door while staring at the screen. https://filedn.eu/lhVNGNsizwl5t7THnzzJ2c8/New%20public/AsiaWire-PhoChina-01.mp4 Surveillance camera footage recorded in the city of Ningbo, located in China's eastern province of Zhejiang, showed the…