//左右轨的图片

//    UIImage *stetchLeftTrack= [UIImage imageNamed:@"zan-jidian.png"];

//    UIImage *stetchRightTrack = [UIImage imageNamed:@"zan-jidian.png"];

//    [self.timeProgress setMinimumTrackImage:stetchLeftTrack forState:UIControlStateNormal];

//    [self.timeProgress setMaximumTrackImage:stetchRightTrack forState:UIControlStateNormal];

//滑块图片

UIImage *thumbImage = [UIImage imageNamed:@"jindu.png"];

//注意这里要加UIControlStateHightlighted的状态，否则当拖动滑块时滑块将变成原生的控件

[self.timeProgress setThumbImage:thumbImage forState:UIControlStateHighlighted];

[self.timeProgress setThumbImage:thumbImage forState:UIControlStateNormal];