OC, oc Language

OC, oc Language
Introduction

• Each UI control automatically creates a layer (root layer) by default, that is, each UI control corresponds to at least one layer.
• Each UIView is associated with a CALayer by default. We can call this Layer as the Root Layer)
• All non-Root layers, I .e. manually created CALayer objects, have implicit animation. What is implicit animation?
• When some attributes of a non-Root Layer are modified, some animation effects are automatically generated by default.
• These attributes are called animation Properties)

• Common Properties of executable implicit Animation

  • Position and size

    • AnchorPoint, anchorPoint
    • Position
    • Bounds, size
    • Frame, position and size
    • Transform, Deformation

  • Appearance

    • BackgroundColor, background color
    • Hidden, whether to hide
    • Opacity, transparency
    • MaskToBounds: whether to cut content beyond the layer area
    • CornerRadius, rounded corner radius

  • Border

    • BorderWidth, Border Width
    • BorderColor, border color

  • Shadow

    • ShadowColor, background color
    • ShadowOffset, background offset
    • ShadowOpacity, background transparency
    • ShadowPath: the path of the background border, that is, the shape of the image that the background displays.
    • ShadowRaduis indicates the radius of the rounded corner of the background.

Example

• Create a UIView object through storyboard and own the object

  @property (weak, nonatomic) IBOutlet UIView *blueView;

• Click on the screen to dynamically modify the animation properties of the layer.

  -(Void) touchesBegan :( NSSet *) touches withEvent :( UIEvent *) event {// generate a random rotation angle using a random number CGFloat angle = angleToRadion (arc4random_uniform (360) + 1 ); // rotate self. blueView. layer. transform = CATransform3DMakeRotation (angle, 0, 0, 1); // move to a random position (50 ~ 249, 50 ~ 449) self. blueView. layer. position = CGPointMake (arc4random_uniform (200) + 50, arc4random_uniform (400) + 50); // set the random radius of the rounded corner self. blueView. layer. cornerRadius = arc4random_uniform (50); // set the random background color self. blueView. layer. backgroundColor = [self randomColor]. CGColor; // set the random Border Width self. blueView. layer. borderWidth = arc4random_uniform (10); // set the random border color self. blueView. layer. borderColor = [self randomColor]. CGColor ;}

• Method for generating random colors

  - (UIColor *)randomColor{return [UIColor colorWithRed:arc4random_uniform(256) / 255.0 green:arc4random_uniform(256) / 255.0 blue:arc4random_uniform(256) / 255.0 alpha:1];}

• Effect