ios中使view向左移动,且右边不动

-(void)signUpAndLoginAnimation:(BOOL)showSignUp {
    CGFloat LogInWidthChange = (showSignUp)?-120:120;
    [UIView animateWithDuration:0.3f
                     animations:^{
                         CGRect newFrame = self.logInView2.frame;
                         newFrame.origin.x -=  LogInWidthChange;
                         newFrame.size.width += LogInWidthChange;
                         
                         CGFloat newSizeX = self.logInView2.frame.size.width + LogInWidthChange;
                         CGFloat ofsetX = LogInWidthChange;
                         
                         [self.logInView2 setFrame:CGRectMake(self.logInView2.frame.origin.x-ofsetX, self.logInView2.frame.origin.y, newSizeX, self.logInView2.frame.size.height)];
                     }];
}

发现写复杂了:

[UIView animateWithDuration:0.3f
                     animations:^{
                         CGFloat changeWidth = (showSignUp)?-120:120;
                         [self.logInView2 setFrame:CGRectMake(self.logInView2.left-changeWidth, self.logInView2.top, self.logInView2.width + changeWidth, self.logInView2.height)];
                     }];

ios中使view向左移动,且右边不动