ios - 如何通过编码xcode改变按钮的位置

Question

我正在尝试对齐通过代码创建的按钮，但我似乎无法更改其位置，我的代码:

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        self.backgroundColor = [UIColor whiteColor];
        self.lineWidth = DEFAULT_WIDTH;
        self.lineColor = DEFAULT_COLOR;
        UIButton* btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
        btn.frame = CGRectMake(20,100, 50, 50);
        //[btn setFrame:CGRectMake(3,20, 50, 50)];
        btn.center = self.center;

        [btn setTitle:@"Clear" forState:UIControlStateNormal];
        [btn addTarget: self 
                   action: @selector(clearButtonPressed:) 
         forControlEvents: UIControlEventTouchDown];
        [self addSubview:btn];
    }
    return self;
}

如果我删除“btn.center =self.center”并尝试将 X 和 Y 位置设置为

    "btn.frame =CGRectMake(3,20,50,50)"

它甚至不显示按钮。请提供任何帮助，在此先感谢!

Answer 1

你试过使用[btn setCenter:center];哪里的中心是 CGPoint？