Ios 为什么赢了'；t将我的文本显示从ViewController上切换到下一个

我试图传递字符串属性，我必须设置标签的文本。但是，该字符串不会显示。我正在浏览多个视图控制器。其思想是从文本字段中获取信息，然后将其存储到属性中。然后在以后的视图控制器中将标签设置为字符串属性

SentenceViewContoller.m
    #import "SentenceViewController.h"
    #import "DrawViewController.h"

    @interface SentenceViewController ()

    @end

    @implementation SentenceViewController

    - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
    {
        self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
        if (self) {
            // Custom initialization
        }
        return self;
    }

    - (void)viewDidLoad
    {
        [super viewDidLoad];
         self.Sentence1TF.text = self.Sent1Str;
        // Do any additional setup after loading the view.
    }

    - (void)didReceiveMemoryWarning
    {
        [super didReceiveMemoryWarning];
        // Dispose of any resources that can be recreated.
    }
    - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
    {

    }


    - (IBAction)stopped:(id)sender {
    }
    @end
-----------------------------------------------------------------------
SentenceViewController.m
    #import "SentenceViewController.h"
    #import "DrawViewController.h"

    @interface SentenceViewController ()

    @end

    @implementation SentenceViewController

    - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
    {
        self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
        if (self) {
            // Custom initialization
        }
        return self;
    }

    - (void)viewDidLoad
    {
        [super viewDidLoad];
         self.Sentence1TF.text = self.Sent1Str;
        // Do any additional setup after loading the view.
    }

    - (void)didReceiveMemoryWarning
    {
        [super didReceiveMemoryWarning];
        // Dispose of any resources that can be recreated.
    }
    - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
    {

    }


    - (IBAction)stopped:(id)sender {
    }
    @end
------------------------------------------------------------------------------
DrawViewController.h

    #import <UIKit/UIKit.h>

    @interface DrawViewController : UIViewController {

    CGPoint lastPoint;
    CGFloat red;
    CGFloat green;
    CGFloat blue;
    CGFloat brush;
    CGFloat opacity;
    BOOL mouseSwiped;
    }

    @property (strong, nonatomic) IBOutlet UIImageView *tempDrawImage;
    @property (strong, nonatomic) IBOutlet UIImageView *mainImage;
    - (IBAction)pencilPressed:(id)sender;
    - (IBAction)eraserPressed:(id)sender;
    @property (weak, nonatomic) IBOutlet UILabel *Sentence1;
    @property (weak, nonatomic) IBOutlet UIButton *Done;
    @property (nonatomic, retain) NSString *Sent1Str;


    @end
------------------------------------------------------------------------
DrawViewController.m

    #import "DrawViewController.h"       
    #import "Draw2ViewController.h"
    #import "SentenceViewController.h"

    @interface DrawViewController ()

    @end

    @implementation DrawViewController

    - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
    {
        self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
        if (self) {
            // Custom initialization
        }
        return self;
    }

    - (void)viewDidLoad
    {
        red = 0.0/255.0;
        green = 0.0/255.0;
        blue = 0.0/255.0;
        brush = 10.0;
        opacity = 1.0;

        [super viewDidLoad];
        //Do any additional setup after loading the view.
        self.Sent1Str = ((SentenceViewController *)self.parentViewController).Sent1Str;
        Draw2ViewController *D2V = [[Draw2ViewController alloc] init];
        D2V.myImage = _mainImage;

        self.Sentence1.text = self.Sent1Str;
    }

    - (void)didReceiveMemoryWarning
    {
        [super didReceiveMemoryWarning];
        // Dispose of any resources that can be recreated.
    }

    - (IBAction)pencilPressed:(id)sender {
        UIButton * PressedButton = (UIButton*)sender;

        switch(PressedButton.tag)
        {
            case 0:
                red = 0.0/255.0;
                green = 0.0/255.0;
                blue = 0.0/255.0;
                break;
            case 1:
                red = 105.0/255.0;
                green = 105.0/255.0;
                blue = 105.0/255.0;
                break;
            case 2:
                red = 255.0/255.0;
                green = 0.0/255.0;
                blue = 0.0/255.0;
                break;
            case 3:
                red = 0.0/255.0;
                green = 0.0/255.0;
                blue = 255.0/255.0;
                break;
            case 4:
                red = 102.0/255.0;
                green = 204.0/255.0;
                blue = 0.0/255.0;
                break;
            case 5:
                red = 102.0/255.0;
                green = 255.0/255.0;
                blue = 0.0/255.0;
                break;
            case 6:
                red = 51.0/255.0;
                green = 204.0/255.0;
                blue = 255.0/255.0;
                break;
            case 7:
                red = 160.0/255.0;
                green = 82.0/255.0;
                blue = 45.0/255.0;
                break;
            case 8:
                red = 255.0/255.0;
                green = 102.0/255.0;
                blue = 0.0/255.0;
                break;
            case 9:
                red = 255.0/255.0;
                green = 255.0/255.0;
                blue = 0.0/255.0;
                break;
        }



    }

    - (IBAction)eraserPressed:(id)sender {

        red = 255.0/255.0;
        green = 255.0/255.0;
        blue = 255.0/255.0;
        opacity = 1.0;
    }
    - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

        mouseSwiped = NO;
        UITouch *touch = [touches anyObject];
        lastPoint = [touch locationInView:self.view];
    }

    - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {

        mouseSwiped = YES;
        UITouch *touch = [touches anyObject];
        CGPoint currentPoint = [touch locationInView:self.view];

        UIGraphicsBeginImageContext(self.view.frame.size);
        [self.tempDrawImage.image drawInRect:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
        CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
        CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), currentPoint.x, currentPoint.y);
        CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
        CGContextSetLineWidth(UIGraphicsGetCurrentContext(), brush );
        CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), red, green, blue, 1.0);
        CGContextSetBlendMode(UIGraphicsGetCurrentContext(),kCGBlendModeNormal);

        CGContextStrokePath(UIGraphicsGetCurrentContext());
        self.tempDrawImage.image = UIGraphicsGetImageFromCurrentImageContext();
        [self.tempDrawImage setAlpha:opacity];
        UIGraphicsEndImageContext();

        lastPoint = currentPoint;
    }

    - (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

        if(!mouseSwiped) {
            UIGraphicsBeginImageContext(self.view.frame.size);
            [self.tempDrawImage.image drawInRect:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
            CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
            CGContextSetLineWidth(UIGraphicsGetCurrentContext(), brush);
            CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), red, green, blue, opacity);
            CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
            CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
            CGContextStrokePath(UIGraphicsGetCurrentContext());
            CGContextFlush(UIGraphicsGetCurrentContext());
            self.tempDrawImage.image = UIGraphicsGetImageFromCurrentImageContext();
            UIGraphicsEndImageContext();
        }

        UIGraphicsBeginImageContext(self.mainImage.frame.size);
        [self.mainImage.image drawInRect:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height) blendMode:kCGBlendModeNormal alpha:1.0];
        [self.tempDrawImage.image drawInRect:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height) blendMode:kCGBlendModeNormal alpha:opacity];
        self.mainImage.image = UIGraphicsGetImageFromCurrentImageContext();
        self.tempDrawImage.image = nil;
        UIGraphicsEndImageContext();
    }
    - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
    {

    }



    @end

-------------------------------------------------------------------------
Draw2ViewController.h

    #import <UIKit/UIKit.h>
    #import "DrawViewController.h"
    #import "ResultsViewController.h"

    @interface Draw2ViewController : UIViewController
    @property (strong, nonatomic) IBOutlet UIImageView *Draw2Image;
    @property (nonatomic, strong) UIImage *myImage;
    @property (weak, nonatomic) IBOutlet UITextField *Sentence2TF;
    - (IBAction)stopped2:(id)sender;
    @property (nonatomic, retain) NSString *Sent1Str;
    @property (nonatomic, retain) NSString *Sent2Str;

    @end
------------------------------------------------------------------------
Draw2ViewController.m

    #import "Draw2ViewController.h"
    #import "DrawViewController.h"
    #import "ResultsViewController.h"

    @interface Draw2ViewController ()

    @end

    @implementation Draw2ViewController

    - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
    {
        self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
        if (self) {
            // Custom initialization
        }
        return self;
    }

    - (void)viewDidLoad
    {
        [super viewDidLoad];
        _Sentence2TF.text = _Sent2Str;
         self.Sent1Str = ((DrawViewController *)self.parentViewController).Sent1Str;

     }

     - (void)didReceiveMemoryWarning
    {
        [super didReceiveMemoryWarning];
        // Dispose of any resources that can be recreated.
     }
     - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
    {

    }



    - (IBAction)stopped2:(id)sender {
    }
    @end
---------------------------------------------------------------------------
ResultsViewController.h

    #import <UIKit/UIKit.h>

    @interface ResultsViewController : UIViewController
    @property (strong, nonatomic) IBOutlet UIImageView *ResultsImage;
    @property (weak, nonatomic) IBOutlet UILabel *Sent1Results;
    @property (weak, nonatomic) IBOutlet UILabel *Sent2Results;
    @property (nonatomic, retain) NSString *Sent2Str;
    @property (nonatomic, retain) NSString *Sent1Str;

    @end
-----------------------------------------------------------------------------
ResultsViewController.m

    #import "ResultsViewController.h"
    #import "Draw2ViewController.h"

    @interface ResultsViewController ()

    @end

    @implementation ResultsViewController

    - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
    {
        self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
        if (self) {
            // Custom initialization

        }
        return self;
    }

    - (void)viewDidLoad
    {
        [super viewDidLoad];
        // Do any additional setup after loading the view.
         self.Sent1Str = ((Draw2ViewController *)self.parentViewController).Sent1Str;
         self.Sent2Str = ((Draw2ViewController *)self.parentViewController).Sent2Str;
        _Sent1Results.text = _Sent1Str;
        _Sent2Results.text = _Sent2Str;
    }

    - (void)didReceiveMemoryWarning
    {
        [super didReceiveMemoryWarning];
        // Dispose of any resources that can be recreated.
    }

    @end

SentenceViewContoller.m
#导入“SentenceViewController.h”
#导入“DrawViewController.h”
@接口语句ViewController（）
@结束
@实现语句视图控制器
-（id）initWithNibName:（NSString*）nibNameOrNil bundle:（NSBundle*）nibBundleOrNil
{
self=[super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]；
如果（自我）{
//自定义初始化
}
回归自我；
}
-（无效）viewDidLoad
{
[超级视图下载]；
self.Sentence1TF.text=self.Sent1Str；
//加载视图后执行任何其他设置。
}
-（无效）未收到记忆警告
{
[超级记忆警告]；
//处置所有可以重新创建的资源。
}
-（void）prepareForSegue:（UIStoryboardSegue*）segue发送方：（id）发送方
{
}
-（iAction）已停止：（id）发送方{
}
@结束
-----------------------------------------------------------------------
SentenceViewController.m
#导入“SentenceViewController.h”
#导入“DrawViewController.h”
@接口语句ViewController（）
@结束
@实现语句视图控制器
-（id）initWithNibName:（NSString*）nibNameOrNil bundle:（NSBundle*）nibBundleOrNil
{
self=[super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]；
如果（自我）{
//自定义初始化
}
回归自我；
}
-（无效）viewDidLoad
{
[超级视图下载]；
self.Sentence1TF.text=self.Sent1Str；
//加载视图后执行任何其他设置。
}
-（无效）未收到记忆警告
{
[超级记忆警告]；
//处置所有可以重新创建的资源。
}
-（void）prepareForSegue:（UIStoryboardSegue*）segue发送方：（id）发送方
{
}
-（iAction）已停止：（id）发送方{
}
@结束
------------------------------------------------------------------------------
DrawViewController.h
#进口
@接口DrawViewController:UIViewController{
CGPoint-lastPoint；
cg-浮红；
绿色；
CGFloat蓝；
CG浮子刷；
CGFloat不透明度；
布尔老鼠；
}
@属性（强，非原子）IBUIImageView*tempDrawImage；
@属性（强，非原子）IBUIImageView*mainImage；
-（i动作）铅笔按下：（id）发送者；
-（iAction）已擦除：（id）发送方；
@性质（弱，非原子）IBUILabel*语句1；
@属性（弱，非原子）IBUIButton*完成；
@属性（非原子，保留）NSString*Sent1Str；
@结束
------------------------------------------------------------------------
DrawViewController.m
#导入“DrawViewController.h”
#导入“Draw2ViewController.h”
#导入“SentenceViewController.h”
@接口DrawViewController（）
@结束
@DrawViewController的实现
-（id）initWithNibName:（NSString*）nibNameOrNil bundle:（NSBundle*）nibBundleOrNil
{
self=[super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]；
如果（自我）{
//自定义初始化
}
回归自我；
}
-（无效）viewDidLoad
{
红色=0.0/255.0；
绿色=0.0/255.0；
蓝色=0.0/255.0；
刷子=10.0；
不透明度=1.0；
[超级视图下载]；
//加载视图后执行任何其他设置。
self.Sent1Str=（（SentenceViewController*）self.parentViewController）.Sent1Str；
Draw2ViewController*D2V=[[Draw2ViewController alloc]init]；
D2V.myImage=\u main image；
self.Sentence1.text=self.Sent1Str；
}
-（无效）未收到记忆警告
{
[超级记忆警告]；
//处置所有可以重新创建的资源。
}
-（iAction）铅笔按下：（id）发送者{
UIButton*按下按钮=（UIButton*）发送器；
开关（按下按钮。标签）
{
案例0：
红色=0.0/255.0；
绿色=0.0/255.0；
蓝色=0.0/255.0；
打破
案例1：
红色=105.0/255.0；
绿色=105.0/255.0；
蓝色=105.0/255.0；
打破
案例2：
红色=255.0/255.0；
绿色=0.0/255.0；
蓝色=0.0/255.0；
打破
案例3：
红色=0.0/255.0；
绿色=0.0/255.0；
蓝色=255.0/255.0；
打破
案例4：
红色=102.0/255.0；
绿色=204.0/255.0；
蓝色=0.0/255.0；
打破
案例5：
红色=102.0/255.0；
绿色=255.0/255.0；
蓝色=0.0/255.0；
打破
案例6：
红色=51.0/255.0；
绿色=204.0/255.0；
蓝色=255.0/255.0；
打破
案例7：
红色=160.0/255.0；
绿色=82.0/255.0；
蓝色=45.0/255.0；
打破
案例8：
红色=255.0/255.0；
绿色=102.0/255.0；
蓝色=0.0/255.0；
打破
案例9：
红色=255.0/255.0；
绿色=255.0/255.0；
蓝色=0.0/255.0；
打破
}
}
-（iAction）已擦除：（id）发送方{
红色=255.0/255.0；
绿色=255.0/255.0；
蓝色=255.0/255.0；
不透明度=1.0；
}
-（无效）接触