iOS Development Basics

First lesson

Ui-uiview Parent-Child Class View auto-scaling

#import "XGOAppDelegate.h"

@implementation Xgoappdelegate

{

UIView *_backview;

}

-(BOOL) Application: (UIApplication *) application didfinishlaunchingwithoptions: (nsdictionary *) launchOptions

{

Self.window = [[Uiwindowalloc] initwithframe:[[uiscreenmainscreen] bounds];

UIView *view1 = [[UIView alloc] init];

View1.frame = CGRectMake (10, 30, 300, 30);

View1.backgroundcolor = [Uicolor Redcolor];

[Self.window Addsubview:view1];

UIView *view2 = [[UIView alloc] init];

View2.frame = CGRectMake (5, 5, 100, 20);

View2.backgroundcolor = [Uicolor Yellowcolor];

[View1 ADDSUBVIEW:VIEW2];

UIView *VIEW3 = [[UIView alloc] init];

View3.frame = CGRectMake (100, 5, 100, 20);

View3.backgroundcolor = [Uicolor Bluecolor];

[View1 ADDSUBVIEW:VIEW3];

Get the parent Class View, where View2, VIEW3 is equivalent to the subclass view, View1 is equivalent to the parent Class View

UIView *superview = View2.superview;

Sets the parent view (view1) background color to Black

Superview.backgroundcolor = [Uicolor blackcolor];

Get an array of sub-class views

Nsarray *subviews = view1.subviews;

NSLog (@ "Count =%d", subviews.count);

VIEW2,VIEW3 turned red.

For (UIView *view in subviews) {

View.backgroundcolor = [Uicolor Redcolor];

//    }

UIView *view = [Subviews objectatindex:0];

View.backgroundcolor = [Uicolor Redcolor];

UIView *blueview = [[UIView alloc] init];

Blueview.frame = CGRectMake (10, 100, 300, 30);

Blueview.backgroundcolor = [Uicolorbluecolor];

If the child view is higher than the parent view, the Clipstobounds property is available: Yes handling

Blueview.clipstobounds = YES;

[Self.window Addsubview:blueview];

UIView *greenview = [[UIView alloc] init];

Greenview.frame = CGRectMake (10, 5, 200, 100);

Greenview.backgroundcolor = [Uicolor Greencolor];

Set the transparency, the smaller the number, the higher the transparency

Greenview.alpha = 0.5;

[Blueview Addsubview:greenview];

Automatic layout

_backview = [[UIView alloc] init];

_backview.frame = CGRectMake (100, 300, 120, 120);

_backview.backgroundcolor = [Uicolor blackcolor];

Allow sub-Class View auto layout

_backview.autoresizessubviews = YES;

[Self.windowaddsubview:_backview];

UIView *topview = [[UIView alloc] init];

Topview.frame = CGRectMake (10, 10, 100, 100);

Topview.backgroundcolor = [Uicolor Orangecolor];

Set Automatic layout width as the parent class automatically increases

Topview.autoresizingmask = Uiviewautoresizingflexiblewidth;

If width and height are added at the same time or | Said

Topview.autoresizingmask = Uiviewautoresizingflexiblewidth | Uiviewautoresizingflexibleheight;

[_backview Addsubview:topview];

[Nstimerscheduledtimerwithtimeinterval:0.5target:selfselector: @selector (Timetick) UserInfo:nilrepeats:YES];

Override point for customization after application launch.

Self.window.backgroundColor = [Uicolor Whitecolor];

[Self.windowmakekeyandvisible];

Returnyes;

}

-(void) Timetick

{

_backview.frame = CGRectMake (_backview.frame.origin.x, _BACKVIEW.FRAME.ORIGIN.Y, _backview.frame.size.width+5, _ BACKVIEW.FRAME.SIZE.HEIGHT+5);

}

@end

iOS Development Basics