Can not display video on uiview

Can not display video on uiview

I try to play video on uiview with AVPlayer, but on my view cannot display
video, it just have voice of my video.This is my code:
NSString *filepath = [[NSBundle mainBundle]
pathForResource:@"WildlifeConverted" ofType:@"mov"];
NSURL *fileURL = [NSURL fileURLWithPath:filepath];
self.playerItem = [AVPlayerItem playerItemWithURL:fileURL];
self.player = [AVPlayer playerWithPlayerItem:playerItem];
[player play];
Please help me to find out and solve the problem. Thanks so much.