IOS draw big Turntable animation Calayer Layer Introduction

1. First to introduce the properties of the next layer

-(void) initimageview{

Initialize ImageView

Uiimageview *imageview = [[Uiimageview alloc]initwithimage:[uiimage imagenamed:@ "1.jpg"]];

Set the IAMGE position to center

Imageview.frame = CGRectMake (kScreenWidth-200)/2, (kScreenHeight-200)/2, 200, 200);

Add to view

[Self.view Addsubview:imageview];

Layer

1. Set shadow color to Cgcolor for yellow type

Imageview.layer.shadowColor = [Uicolor Yellowcolor]. Cgcolor;

2. Set the shadow offset size

Imageview.layer.shadowOffset = Cgsizemake (10, 10);

3. Set the opacity of the shadow

imageview.layer.shadowOpacity = 0.5;

4. Set the fillet size

Imageview.layer.cornerRadius = 20;//Set fillet radius to 10

Force all child layers inside to support rounded effects don't show shadow effects

Imageview.layer.masksToBounds = YES;

5. Set the border

Imageview.layer.borderWidth = 5;

Imageview.layer.borderColor = [Uicolor Redcolor]. Cgcolor;

6. Set rotation, zoom clockwise rotate four per cent along the XY axis pi

Imageview.layer.transform = Catransform3dmakerotation (M_pi_4, 1, 1, 0);

Rotate four per cent of Pi clockwise along the z axis

Imageview.layer.transform = Catransform3dmakerotation (M_pi_4, 1, 1, 0);

7. Set Zoom x axis Zoom 0.5

Imageview.layer.transform = Catransform3dmakescale (0.5, 0.5, 0.5);

2. How to create a layer

Creating the framework contained in the Quartzcore framework through a class method is a cross-platform need to be added to the header file and added to the link framework

Calayer *layer = [Calayer layer];

Set the properties of a layer layer

Set Background color Gray

Layer.backgroundcolor = [Uicolor Graycolor]. Cgcolor;

Set layer Bounds

Layer.bounds = CGRectMake (0, 0, 100, 100);

/*

*position sets the position of Calayer in the parent layer with the upper-left corner of the parent layer as the origin (0,0)

The *anchorpoint Anchor Point (the anchor) determines which point of the calayer is in the position referred to by the Position property, with its upper-left corner as the origin (0,0) default (0.5,0.5) X~y The value is 0-1 lower right (1,1)

*/

Set the layer position

Layer.position = Cgpointmake (200, 200);

Set anchor points for layer

Layer.anchorpoint = Cgpointmake (0, 1);

Set the contents of layer

Layer.contents = (__bridge ID _nullable) ([UIImage imagenamed:@ "1.jpg"]. Cgimage);

Add Layers

[Self.view.layer Addsublayer:layer];

3. Custom Layers

3.1 Establish a subclass to inherit from the parent class Calayer

#import "KLayer.h"

@implementation Klayer

Implement Drawincontext method

-(void) Drawincontext: (cgcontextref) ctx{

Set color

Cgcontextsetrgbfillcolor (CTX, 1, 0, 0, 0.5);

Draw a circle and a high equal ellipse on the view

Cgcontextaddellipseinrect (CTX, cgrectmake (0, 0, 100, 100));

Draw the circle to the view

Cgcontextfillpath (CTX);

}

@end

The following methods are implemented in VIEWCONTROLLER.M

-(void) Viewdidload {

[Super Viewdidload];

[Self initlayer];

}

Initialize a custom layer

-(void) initlayer{

Klayer *layer = [Klayer layer];

Set the size of a layer

Layer.bounds = CGRectMake (0, 0, 200, 200);

Layer.anchorpoint = cgpointmake (0, 0);

The second method of proxy

Layer.delegate = self;//Without protocol any object can be a proxy

[Layer setneedsdisplay];//must call this method layer will not display

Add Layers

[Self.view.layer Addsublayer:layer];

}

The way to implement this agent through the broker

#pragma mark Layer Agent method

You can draw layers in this proxy method

-(void) Drawlayer: (Calayer *) layer Incontext: (cgcontextref) ctx{

Set color

Cgcontextsetrgbfillcolor (CTX, 0, 0, 1, 1);

Draw a circle and a high equal ellipse on the view

Cgcontextaddellipseinrect (CTX, cgrectmake (0, 0, 100, 100));

Draw the circle to the view

Cgcontextfillpath (CTX);

}