OC 实现UIView 四个角独立拖动

效果

.....gif
源码

//
//  ViewController.m
//  panDemo
//
//  Created by ifun on 2023/7/7.
//

#import "ViewController.h"

typedef NS_ENUM(NSUInteger, mainViewBtnType) {
    mainViewBtnTypeNone = 0,
    mainViewBtnTypeLeftUp,
    mainViewBtnTypeRightUp,
    mainViewBtnTypeLeftDown,
    mainViewBtnTypeRightDown,
    mainViewBtnTypeCenter
};

@interface ViewController ()

@property(nonatomic,strong)UIView *mainView;

@property(nonatomic,strong)UIButton *submitBtn;


@property(nonatomic,assign)CGPoint startedPoint;

@property(nonatomic,assign)CGRect mainViewStartedFrame;

@property(nonatomic,assign)mainViewBtnType btnType;

@property(nonatomic,strong)NSLayoutConstraint *layoutConstraint_left;

@property(nonatomic,strong)NSLayoutConstraint *layoutConstraint_width;

@property(nonatomic,strong)NSLayoutConstraint *layoutConstraint_top;

@property(nonatomic,strong)NSLayoutConstraint *layoutConstraint_height;

@property(nonatomic,assign)CGFloat minWidth;//最小宽高

@property(nonatomic,assign)CGFloat minHeight;

@property(nonatomic,assign)CGFloat tocuhDia;//四个角的触摸直径,除了4个角，其余都是中间的触摸事件

@property(nonatomic,strong)UIView *lastTopLine;

@property(nonatomic,strong)UIView *lastDownLine;

@property(nonatomic,strong)UIView *lastLeftLine;

@property(nonatomic,strong)UIView *lastRightLine;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor grayColor];
    self.minWidth =
    self.minHeight = CGRectGetWidth(self.view.frame)/3;
    
    self.tocuhDia = self.minWidth/3;
    
    [self mainView];
    [self submitBtn];
    
    // Do any additional setup after loading the view.
}

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    NSLog(@"touchesBegan touches.count:%lu",(unsigned long)touches.count);
    UITouch *touch = [touches anyObject];
    CGPoint point = [touch locationInView:self.view];
    self.startedPoint = point;
    self.mainViewStartedFrame = self.mainView.frame;
    
    if (CGRectContainsPoint(self.mainView.frame, point)){
        CGPoint pointFingerInView = [touch locationInView:self.mainView];
        if(CGRectContainsPoint(CGRectMake(0, 0, self.tocuhDia, self.tocuhDia), pointFingerInView)){
            self.btnType = mainViewBtnTypeLeftUp;
        }else if (CGRectContainsPoint(CGRectMake(self.mainView.frame.size.width - self.tocuhDia, 0, self.tocuhDia, self.tocuhDia), pointFingerInView)){
            self.btnType = mainViewBtnTypeRightUp;
        }else if (CGRectContainsPoint(CGRectMake(0, self.mainView.frame.size.height - self.tocuhDia, self.tocuhDia, self.tocuhDia), pointFingerInView)){
            self.btnType = mainViewBtnTypeLeftDown;
        }else if (CGRectContainsPoint(CGRectMake(self.mainView.frame.size.width - self.tocuhDia, self.mainView.frame.size.height - self.tocuhDia, self.tocuhDia, self.tocuhDia), pointFingerInView)){
            self.btnType = mainViewBtnTypeRightDown;
        }else{
            self.btnType = mainViewBtnTypeCenter;
        }
    }
}

- (void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    NSLog(@"touchesMoved touches.count:%lu",(unsigned long)touches.count);
    UITouch *touch = [touches anyObject];
    CGPoint point = [touch locationInView:self.view];
    
    CGFloat movedWidth = point.x - self.startedPoint.x;
    CGFloat movedHeight = point.y - self.startedPoint.y;
    NSLog(@"btnType:%lu ==>movedWidth:%.4f@===>movedHeight:%.4f",(unsigned long)self.btnType,movedWidth,movedHeight);
    switch (self.btnType) {
        case mainViewBtnTypeNone:break;
        case mainViewBtnTypeLeftUp:{
            self.mainView.frame = CGRectMake(MIN(MAX(CGRectGetMinX(self.mainViewStartedFrame) + movedWidth, 0), CGRectGetMaxX(self.mainViewStartedFrame) - self.minWidth),
                                             MIN(MAX(CGRectGetMinY(self.mainViewStartedFrame) + movedHeight, 0), CGRectGetMaxY(self.mainViewStartedFrame)- self.minHeight),
                                             MAX(CGRectGetWidth(self.mainViewStartedFrame) - movedWidth, self.minWidth),
                                             MAX(CGRectGetHeight(self.mainViewStartedFrame) - movedHeight, self.minHeight));
        }break;
        case mainViewBtnTypeRightUp:{
            self.mainView.frame = CGRectMake(CGRectGetMinX(self.mainViewStartedFrame),
                                             MIN(MAX(CGRectGetMinY(self.mainViewStartedFrame) + movedHeight, 0), CGRectGetMaxY(self.mainViewStartedFrame)- self.minHeight),
                                             MAX(CGRectGetWidth(self.mainViewStartedFrame) + movedWidth, self.minWidth),
                                             MAX(CGRectGetHeight(self.mainViewStartedFrame) - movedHeight, self.minHeight));
        }break;
        case mainViewBtnTypeLeftDown:{
            self.mainView.frame = CGRectMake(MIN(MAX(CGRectGetMinX(self.mainViewStartedFrame) + movedWidth, 0), CGRectGetMaxX(self.mainViewStartedFrame) - self.minWidth),
                                             CGRectGetMinY(self.mainViewStartedFrame),
                                             MAX(CGRectGetWidth(self.mainViewStartedFrame) - movedWidth, self.minWidth),
                                             MAX(CGRectGetHeight(self.mainViewStartedFrame) + movedHeight, self.minHeight));
        }break;
        case mainViewBtnTypeRightDown:{
            self.mainView.frame = CGRectMake(CGRectGetMinX(self.mainViewStartedFrame),
                                             CGRectGetMinY(self.mainViewStartedFrame),
                                             MIN(MAX(CGRectGetWidth(self.mainViewStartedFrame) + movedWidth, self.minWidth), CGRectGetWidth(self.view.frame) - CGRectGetMinX(self.mainView.frame)),
                                             MIN(MAX(CGRectGetHeight(self.mainViewStartedFrame) + movedHeight, self.minHeight), CGRectGetHeight(self.view.frame) - CGRectGetMinY(self.mainView.frame)));
        }break;
        case mainViewBtnTypeCenter:{
            self.mainView.frame = CGRectMake(MIN(MAX(CGRectGetMinX(self.mainViewStartedFrame) + movedWidth, 0), CGRectGetWidth(self.view.frame) - CGRectGetWidth(self.mainViewStartedFrame)) ,
                                             MIN(MAX(CGRectGetMinY(self.mainViewStartedFrame) + movedHeight, 0), CGRectGetHeight(self.view.frame) - CGRectGetHeight(self.mainViewStartedFrame)) ,
                                             CGRectGetWidth(self.mainViewStartedFrame),
                                             CGRectGetHeight(self.mainViewStartedFrame));
        }break;
        default:
            break;
    }
}

- (void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    self.btnType = mainViewBtnTypeNone;
}

- (void)touchesCancelled:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    self.btnType = mainViewBtnTypeNone;
}

-(UIView *)mainView{
    if(!_mainView){
        _mainView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.minWidth, self.minHeight)];
        _mainView.backgroundColor = [UIColor blackColor];
        _mainView.center = self.view.center;
        [self.view addSubview:_mainView];
    }
    return _mainView;
}

-(UIButton *)submitBtn{
    if(!_submitBtn){
        _submitBtn = [[UIButton alloc] initWithFrame:CGRectMake(40, 40, 50, 30)];
        _submitBtn.backgroundColor = [UIColor blueColor];
        [_submitBtn addTarget:self action:@selector(showLine) forControlEvents:UIControlEventTouchUpInside];
        [self.view addSubview:_submitBtn];
    }
    return _submitBtn;
}

-(void)showLine{
    //画顶部的线条
    [self showTopLine];
    //画左边的线条
    [self showLeftLine];
    //画右边的线条
    [self showRightLine];
    //画下边的线条
    [self showDownLine];
}

-(void)showTopLine{
    if(self.lastTopLine == nil){
        UIView *line = [[UIView alloc] initWithFrame:CGRectMake(0, CGRectGetMinY(self.mainView.frame) , self.view.frame.size.width, 1)];
        line.backgroundColor = [UIColor redColor];
        [self.view addSubview:line];
        self.lastTopLine = line;
        [self showTopLine];
    }else{
        if((CGRectGetMinY(self.lastTopLine.frame) - self.mainView.frame.size.height ) > 0){
            UIView *line = [[UIView alloc] initWithFrame:CGRectMake(0, (CGRectGetMinY(self.lastTopLine.frame) - self.mainView.frame.size.height) , self.view.frame.size.width, 1)];
            line.backgroundColor = [UIColor redColor];
            [self.view addSubview:line];
            self.lastTopLine = line;
            [self showTopLine];
        }else{
            self.lastTopLine = nil;
        }
    }
}

-(void)showLeftLine{
    if(self.lastLeftLine == nil){
        UIView *line = [[UIView alloc] initWithFrame:CGRectMake(CGRectGetMinX(self.mainView.frame),0, 1, self.view.frame.size.height)];
        line.backgroundColor = [UIColor redColor];
        [self.view addSubview:line];
        self.lastLeftLine = line;
        [self showLeftLine];
    }else{
        if((CGRectGetMinX(self.lastLeftLine.frame) - self.mainView.frame.size.width ) > 0){
            UIView *line = [[UIView alloc] initWithFrame:CGRectMake((CGRectGetMinX(self.lastLeftLine.frame) - self.mainView.frame.size.width),0 , 1, self.view.frame.size.height)];
            line.backgroundColor = [UIColor redColor];
            [self.view addSubview:line];
            self.lastLeftLine = line;
            [self showLeftLine];
        }else{
            self.lastLeftLine = nil;
        }
    }
}

-(void)showRightLine{
    if(self.lastRightLine == nil){
        UIView *line = [[UIView alloc] initWithFrame:CGRectMake(CGRectGetMaxX(self.mainView.frame),0, 1,self.view.frame.size.height)];
        line.backgroundColor = [UIColor redColor];
        [self.view addSubview:line];
        self.lastRightLine = line;
        [self showRightLine];
    }else{
        if((CGRectGetMaxX(self.lastRightLine.frame) + self.mainView.frame.size.width ) < self.view.frame.size.width){
            UIView *line = [[UIView alloc] initWithFrame:CGRectMake((CGRectGetMaxX(self.lastRightLine.frame) + self.mainView.frame.size.width ),0, 1,self.view.frame.size.height)];
            line.backgroundColor = [UIColor redColor];
            [self.view addSubview:line];
            self.lastRightLine = line;
            [self showRightLine];
        }else{
            self.lastRightLine = nil;
        }
    }
}

-(void)showDownLine{
    if(self.lastDownLine == nil){
        UIView *line = [[UIView alloc] initWithFrame:CGRectMake(0, CGRectGetMaxY(self.mainView.frame) , self.view.frame.size.width, 1)];
        line.backgroundColor = [UIColor redColor];
        [self.view addSubview:line];
        self.lastDownLine = line;
        [self showDownLine];
    }else{
        if((CGRectGetMaxY(self.lastDownLine.frame) + self.mainView.frame.size.height ) < self.view.frame.size.height){
            UIView *line = [[UIView alloc] initWithFrame:CGRectMake(0, (CGRectGetMaxY(self.lastDownLine.frame) + self.mainView.frame.size.height ) , self.view.frame.size.width, 1)];
            line.backgroundColor = [UIColor redColor];
            [self.view addSubview:line];
            self.lastDownLine = line;
            [self showDownLine];
        }else{
            self.lastDownLine = nil;
        }
    }
}
@end
OC 实现UIView 四个角 独立 拖动

效果

源码

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OC 实现UIView 四个角独立拖动
