该图是直接设置UIView透明度为0.7的效果
imageView 不要加到黑色半透明的view上边 这样设置alpha不会影响到imageView
soeasy, 你只要设置你的半透明的黑色背景的background.
blackView.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.5];
就OK啦。
UIView *blackView = [UIView new];
blackView.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.5];
[self.view addSubview:blackView];
[blackView mas_makeConstraints:^(MASConstraintMaker *make) {
make.size.equalTo(self.view);
make.center.equalTo(self.view);
}];
UIImageView *topImageView = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"fenxiang"]];
[blackView addSubview:topImageView];
[topImageView mas_makeConstraints:^(MASConstraintMaker *make) {
make.edges.equalTo(blackView).insets(UIEdgeInsetsMake(200, 50, 100, 50));
}];