IOS不用AutoLayout也能实现自动布局的类(2)----MyFrameLayout横空出世

下载地址：

https://github.com/youngsoft/MyLinearLayout



我们知道，在IOS中我们要想进行视图的各方向的停靠，需要用到autoresizingMask，以及不停的计算应该停靠的位置，也就是计算frame中的x,y,width,height，这样大量的编码导致计算繁琐而且容易出错，因此我这里推出了另外新的布局模式MyFrameLayout。这个布局可以让子视图实现左中右，上中下，填充等功能的布局，同时还可以设置停靠的布局的位置的边距，我们对子视图扩展出了停靠位置的属性：

@property(nonatomic,assign)MarignGravity marginGravity;

这个属性用来控制子视图停靠在MyFrameLayout的方位，这些方位可以是如下方位的或组合：

MGR***ITY_NONE //不采用停靠模式

MGR***ITY_HORZ_LEFT //水平居左
MGR***ITY_HORZ_CENTER //水平居中
MGR***ITY_HORZ_RIGHT //水平居右

MGR***ITY_HORZ_FILL //水平填充整个布局，视图会有拉伸
MGR***ITY_VERT_TOP //垂直居上
MGR***ITY_VERT_CENTER //垂直居中
MGR***ITY_VERT_BOTTOM //垂直居下
MGR***ITY_VERT_FILL //垂直填充整个布局，视图会有拉伸

MGR***ITY_CENTER //整个视图居中

MGR***ITY_FILL //整个视图填满布局视图

除了可以让子视图停靠在布局的方位外，还可以指定子视图离停靠位置的边距，这个可以通过扩展的视图的四个属性：

@property(nonatomic,assign)CGFloat topMargin;

@property(nonatomic,assign)CGFloat leftMargin;

@property(nonatomic,assign)CGFloat bottomMargin;

@property(nonatomic,assign)CGFloat rightMargin;

这四个属性用来设置视图离停靠位置的四个距离。同时MyFrameLayout中还提供一个padding的属性用来控制整体的子视图离自己的边距。
因为这个布局的使用比较简单，下面直接可以看图：



对应的代码如下：

MyFrameLayout *fl = [[MyFrameLayout alloc] initWithFrame:self.view.bounds];
    fl.autoresizingMask =  UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
    fl.padding = UIEdgeInsetsMake(20, 20, 20, 20);
    fl.backgroundColor = [UIColor grayColor];
    
    //显示全屏
    UILabel *fill = UILabel.new;
    fill.text = @"                fill";
   // fill.textAlignment = NSTextAlignmentCenter;
    fill.backgroundColor = [UIColor blueColor];
    fill.marginGravity = MGR***ITY_FILL;
    [fl addSubview:fill];
    
    
    
    //左右填充。
    UILabel *horzFill = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 0, 120)];
    horzFill.text = @"Horz Fill";
    horzFill.textAlignment = NSTextAlignmentCenter;
    horzFill.backgroundColor = [UIColor greenColor];
    horzFill.marginGravity = MGR***ITY_HORZ_FILL;
    [fl addSubview:horzFill];
    
    
    //左右居中
    UILabel *horzCenter = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 100, 50)];
    horzCenter.text = @"Horz Center";
    horzCenter.backgroundColor = [UIColor whiteColor];
    horzCenter.marginGravity = MGR***ITY_HORZ_CENTER;
    [fl addSubview:horzCenter];

    
    //左上
    UILabel *topLeft = UILabel.new;
    topLeft.text = @"topLeft";
    [topLeft sizeToFit];
    topLeft.backgroundColor = [UIColor whiteColor];
    topLeft.marginGravity = MGR***ITY_HORZ_LEFT | MGR***ITY_VERT_TOP;
    [fl addSubview:topLeft];
    
    //左中
    UILabel *centerLeft = UILabel.new;
    centerLeft.text = @"centerLeft";
    [centerLeft sizeToFit];
    centerLeft.backgroundColor = [UIColor whiteColor];
    centerLeft.marginGravity = MGR***ITY_HORZ_LEFT | MGR***ITY_VERT_CENTER;
    [fl addSubview:centerLeft];
    
    
    //左下
    UILabel *bottomLeft = UILabel.new;
    bottomLeft.text = @"bottomLeft";
    [bottomLeft sizeToFit];
    bottomLeft.backgroundColor = [UIColor whiteColor];
    bottomLeft.marginGravity = MGR***ITY_HORZ_LEFT | MGR***ITY_VERT_BOTTOM;
    [fl addSubview:bottomLeft];
    
    
    //中上
    UILabel *topCenter = UILabel.new;
    topCenter.text = @"topCenter";
    [topCenter sizeToFit];
    topCenter.backgroundColor = [UIColor greenColor];
    topCenter.marginGravity = MGR***ITY_HORZ_CENTER | MGR***ITY_VERT_TOP;
    [fl addSubview:topCenter];
    
    
    //中中。
    UILabel *centerCenter = UILabel.new;
    centerCenter.text = @"centerCenter";
    [centerCenter sizeToFit];
    centerCenter.backgroundColor = [UIColor greenColor];
    centerCenter.marginGravity = MGR***ITY_HORZ_CENTER | MGR***ITY_VERT_CENTER;
    [fl addSubview:centerCenter];
    
    
    //中下
    UILabel *bottomCenter = UILabel.new;
    bottomCenter.text = @"bottomCenter";
    [bottomCenter sizeToFit];
    bottomCenter.backgroundColor = [UIColor greenColor];
    bottomCenter.marginGravity = MGR***ITY_HORZ_CENTER | MGR***ITY_VERT_BOTTOM;
    [fl addSubview:bottomCenter];

    
    //右上
    UILabel *topRight = UILabel.new;
    topRight.text = @"topRight";
    [topRight sizeToFit];
    topRight.backgroundColor = [UIColor greenColor];
    topRight.marginGravity = MGR***ITY_HORZ_RIGHT | MGR***ITY_VERT_TOP;
    [fl addSubview:topRight];
    
    
    //右中
    UILabel *centerRight = UILabel.new;
    centerRight.text = @"centerRight";
    [centerRight sizeToFit];
    centerRight.backgroundColor = [UIColor greenColor];
    centerRight.marginGravity = MGR***ITY_HORZ_RIGHT | MGR***ITY_VERT_CENTER;
    [fl addSubview:centerRight];

    
    UILabel *bottomRight = UILabel.new;
    bottomRight.text = @"bottomRight";
    [bottomRight sizeToFit];
    bottomRight.backgroundColor = [UIColor greenColor];
    bottomRight.marginGravity = MGR***ITY_HORZ_RIGHT | MGR***ITY_VERT_BOTTOM;
    [fl addSubview:bottomRight];
    

    //居中显示。
    UILabel *center = UILabel.new;
    center.text = @"center";
    [center sizeToFit];
    center.backgroundColor = [UIColor redColor];
    center.marginGravity = MGR***ITY_CENTER;
    center.leftMargin = 30;
    center.rightMargin = 30;
    center.topMargin = 30;
    center.bottomMargin = 30;
    [fl addSubview:center];

    
    [self.view addSubview:fl];

从代码中我们可以看到每个视图只需要设置marginGravity的对应的停靠的位置，以及设置对应的xxxMargin边距，还有设置MyFrameLayout的padding值来设置里面里面的子视图离自己的边距。

总结：
对于那些希望固定在某个位置的子视图来说，我们可以通过将视图加入到MyFrameLayout中来实现。

https://github.com/youngsoft/MyLinearLayout