如何在SpriteKit中使用UITextView？

Question

So I have this UITextView in my game, and I want to make it more dynamic by adding SKAction animations and having it interact with physics . The former I did in kind of a hacky way which I'm not quite satisfied with, the latter I haven't done as I haven't a clue how to.

This is how I did the SKActions:

I made a couple of ivars:

- textViewContent (NSString)

- textViewSize (CGRect)

- textView (UITextView)

- fakeTextView (SKSpriteNode)

Called by didMoveToView:

-(void)createTextView {

    textViewContent = @"foo";
    textViewSize = CGRectMake(CGRectGetMidX(self.frame)-(self.frame.size.width/4),
                          CGRectGetMidY(self.frame)-(self.frame.size.height/4), self.frame.size.width/2, self.frame.size.height/2);


    textView = [[UITextView alloc]initWithFrame:textViewSize];

    textView.backgroundColor = [SKColor orangeColor];
    textView.text = textViewContent;
    textView.textColor = [SKColor whiteColor];
    textView.textAlignment = NSTextAlignmentLeft;
    textView.font = [UIFont fontWithName:@"Code-Pro-Demo" size:25];
    textView.layer.zPosition = -1;
    textView.alpha = 0;
    textView.editable = NO;


    fakeTextView = [SKSpriteNode spriteNodeWithColor:[SKColor orangeColor] size:CGSizeMake(self.frame.size.width/2, self.frame.size.height/2)];
    fakeTextView.position = CGPointMake((self.frame.size.width*1.5),CGRectGetMidY(self.frame));
    [self addChild:fakeTextView];
    [self textViewEntersScene];


}
-(void)textViewEntersScene{
    SKAction *wait = [SKAction waitForDuration:0.5];
    SKAction *moveIn = [SKAction moveToX:(self.frame.size.width/2) - 100 duration:0.3];
    SKAction *moveBackSlightly = [SKAction moveToX:self.frame.size.width/2 duration:0.2];

    SKAction *displayTextView = [SKAction runBlock:^{
        textView.alpha = 1;
}];

    SKAction *hideFakeTextView = [SKAction runBlock:^{
        fakeTextView.hidden = YES;
}];  

    [fakeTextView runAction:[SKAction sequence:@[wait,moveIn,moveBackSlightly,displayTextView,hideFakeTextView]]];


}

As you can probably tell, the possibilities are very limited. Is there a better way of achieving this or something similar?

Answer 1

I created a class to display and scroll text. You can do a straight copy and paste for the .h and .m files once you create a new SKNode class.

Basically the class displays SKLabelNodes and scrolls them up if there is more than 1 line. Lines appear for a set time, move up if additional lines are added and then fade out.

It's pretty generic stuff so feel free to use and modify the code in any project you want.

To use the class, import the header and use this code (example):

TextBubble *myBubble = [[TextBubble alloc] init];
[myBubble createBubbleWithText:@"Hello this is a very nice day to go fishing and have a cold beer." textSize:24 maxLineLength:20];
myBubble.position = CGPointMake(300, 300);
[self addChild:myBubble];

TextBubble Header File

#import <SpriteKit/SpriteKit.h>

@interface TextBubble : SKNode

-(instancetype)init;
-(void)createBubbleWithText:(NSString *)textString textSize:(int)textSize maxLineLength:(int)maxLineLength;

@end

TextBubble Implementation File

#import "TextBubble.h"

@implementation TextBubble {
    NSMutableArray *linesArray;
}

- (instancetype)init {
    self = [super init];
    if (self) {
        linesArray = [[NSMutableArray alloc] init];
    }
    return self;
}

-(void)createBubbleWithText:(NSString *)textString textSize:(int)textSize maxLineLength:(int)maxLineLength {

    NSMutableString *passedText = [[NSMutableString alloc] initWithString:textString];
    NSMutableString *currentLine = [[NSMutableString alloc] init];
    unsigned long characterCounter = 0;
    BOOL keepGoing = true;

    while (keepGoing) {

        NSRange whiteSpaceRange = [passedText rangeOfCharacterFromSet:[NSCharacterSet whitespaceCharacterSet]];

        if(whiteSpaceRange.location != NSNotFound) {
            characterCounter += whiteSpaceRange.location+1;

            if(characterCounter <= maxLineLength) {
                [currentLine appendString:[passedText substringWithRange:NSMakeRange(0, whiteSpaceRange.location+1)]];
                [passedText setString:[passedText substringWithRange:NSMakeRange(whiteSpaceRange.location+1, [passedText length]-whiteSpaceRange.location-1)]];
            } else {
                [currentLine setString:[currentLine substringWithRange:NSMakeRange(0, [currentLine length]-1)]];

                SKLabelNode *myNode = [SKLabelNode labelNodeWithFontNamed:@"Arial-BoldMT"];
                myNode.text = [NSString stringWithString:currentLine];
                myNode.fontSize = textSize;
                myNode.fontColor = [SKColor blueColor];
                myNode.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeCenter;
                myNode.verticalAlignmentMode = SKLabelVerticalAlignmentModeCenter;
                myNode.zPosition = 0;
                [linesArray addObject:myNode];

                characterCounter = 0;
                [currentLine setString:@""];
            }
        } else {
            [currentLine appendString:passedText];

            SKLabelNode *myNode = [SKLabelNode labelNodeWithFontNamed:@"Arial-BoldMT"];
            myNode.text = [NSString stringWithString:currentLine];
            myNode.fontSize = textSize;
            myNode.fontColor = [SKColor blueColor];
            myNode.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeCenter;
            myNode.verticalAlignmentMode = SKLabelVerticalAlignmentModeCenter;
            myNode.zPosition = 0;
            [linesArray addObject:myNode];

            keepGoing = false;
        }
    }

    if([linesArray count] == 1) {
        SKAction *block0 = [SKAction runBlock:^{
            SKLabelNode *myNode = [linesArray objectAtIndex:0];
            myNode.alpha = 0.0;
            [self addChild:myNode];
            [myNode runAction:[SKAction fadeAlphaTo:1.0 duration:0.5]];
        }];

        SKAction *wait1 = [SKAction waitForDuration:2.5];

        SKAction *block1 = [SKAction runBlock:^{
            SKLabelNode *myNode = [linesArray objectAtIndex:0];
            [myNode runAction:[SKAction fadeAlphaTo:0.0 duration:0.5]];
        }];

        SKAction *wait2 = [SKAction waitForDuration:0.5];

        SKAction *block2 = [SKAction runBlock:^{
            [[linesArray objectAtIndex:0] removeFromParent];
        }];

        [self runAction:[SKAction sequence:@[block0, wait1, block1, wait2, block2]]];
    }

    if([linesArray count] == 2) {
        float heightCounter = 0.0;

        for (int i = 0; i<[linesArray count]; i++) {

            SKAction *wait0 = [SKAction waitForDuration:(2.0 * i)];

            SKAction *block0 = [SKAction runBlock:^{
                SKLabelNode *myNode = [linesArray objectAtIndex:i];
                myNode.alpha = 0.0;
                myNode.position = CGPointMake(0, 0);
                [self addChild:myNode];
                [[linesArray objectAtIndex:i] runAction:[SKAction fadeAlphaTo:1.0 duration:0.5]];
            }];

            SKAction *wait1 = [SKAction waitForDuration:1.5];

            heightCounter += 30;

            SKAction *block1 = [SKAction runBlock:^{
                [[linesArray objectAtIndex:i] runAction:[SKAction moveToY:heightCounter duration:0.5]];
            }];

            SKAction *block2 = [SKAction runBlock:^{
                [[linesArray objectAtIndex:i] runAction:[SKAction fadeAlphaTo:0.0 duration:0.5]];
            }];

            SKAction *wait2 = [SKAction waitForDuration:0.5];

            SKAction *block3 = [SKAction runBlock:^{
                [[linesArray objectAtIndex:i] removeFromParent];
            }];

            [self runAction:[SKAction sequence:@[wait0, block0, wait1, block1, wait1, block2, wait2, block3]]];

            heightCounter = 0;
        }
    }

    if([linesArray count] >= 3) {
        float heightCounter = 0.0;

        for (int i = 0; i<[linesArray count]; i++) {

            SKAction *wait0 = [SKAction waitForDuration:(1.5 * i)];

            SKAction *block0 = [SKAction runBlock:^{
                SKLabelNode *myNode = [linesArray objectAtIndex:i];
                myNode.alpha = 0.0;
                myNode.position = CGPointMake(0, 0);
                [self addChild:myNode];
                [[linesArray objectAtIndex:i] runAction:[SKAction fadeAlphaTo:1.0 duration:0.5]];
            }];

            SKAction *wait1 = [SKAction waitForDuration:1.5];

            heightCounter += 30;

            SKAction *block1 = [SKAction runBlock:^{
                [[linesArray objectAtIndex:i] runAction:[SKAction moveToY:heightCounter duration:0.5]];
            }];

            heightCounter += 30;

            SKAction *block5 = [SKAction runBlock:^{
                [[linesArray objectAtIndex:i] runAction:[SKAction moveToY:heightCounter duration:0.5]];
            }];

            SKAction *block2 = [SKAction runBlock:^{
                [[linesArray objectAtIndex:i] runAction:[SKAction fadeAlphaTo:0.0 duration:0.5]];
            }];

            SKAction *wait2 = [SKAction waitForDuration:0.5];

            SKAction *block3 = [SKAction runBlock:^{
                [[linesArray objectAtIndex:i] removeFromParent];
            }];

            [self runAction:[SKAction sequence:@[wait0, block0, wait1, block1, wait1, block5, wait1, block2, wait2, block3]]];

            heightCounter = 0;
        }
    }
}

@end