在Sprite Kit中创建按钮的正确方法？
问题描述：
我正在制作游戏，我想要一个按钮。我如何处理它？
我为UI使用单独的类，它是包含所有按钮和界面元素的SKSpriteNode，我不希望Scene在触摸开始方法中为我处理那些按钮按下。
I'm making a game and I want to have a button. How do I handle tapping it? I use separate class for UI, it is SKSpriteNode that holds all buttons and interface elements, and I don't want Scene to handle those button presses for me in touches began method.
据我所知，我们可以检查触摸中触摸的节点是否开始，所以要实现内置触摸的常规按钮我需要在touchesBegan和touchesEnded中编写代码，这看起来有点矫枉过正。
As I know we can check for node that is being touched in touches began, so to implement regular button with touch up inside I need to write code in touchesBegan and touchesEnded, this looks like a bit overkill.
或者我应该使用常规UIButton吗？但我知道你不能动态地添加它们，只能在didMoveToView方法中，这看起来很糟糕。
Or should I use regular UIButton? But I know that you can't add those dynamically, only in didMoveToView method, and this looks bad.
答
我发现这个不久前在网上，由一位名叫格拉芙的成员提供，这很适合我的问题。
I found this online a while ago, courtesy of a member who goes by the name of Graf, this works nicely for my problems.
#import <SpriteKit/SpriteKit.h>
@interface SKBButtonNode : SKSpriteNode
@property (nonatomic, readonly) SEL actionTouchUpInside;
@property (nonatomic, readonly) SEL actionTouchDown;
@property (nonatomic, readonly) SEL actionTouchUp;
@property (nonatomic, readonly, weak) id targetTouchUpInside;
@property (nonatomic, readonly, weak) id targetTouchDown;
@property (nonatomic, readonly, weak) id targetTouchUp;
@property (nonatomic) BOOL isEnabled;
@property (nonatomic) BOOL isSelected;
@property (nonatomic, readonly, strong) SKLabelNode *title;
@property (nonatomic, readwrite, strong) SKTexture *normalTexture;
@property (nonatomic, readwrite, strong) SKTexture *selectedTexture;
@property (nonatomic, readwrite, strong) SKTexture *disabledTexture;
- (instancetype)initWithTextureNormal:(SKTexture *)normal selected:(SKTexture *)selected;
- (instancetype)initWithTextureNormal:(SKTexture *)normal selected:(SKTexture *)selected disabled:(SKTexture *)disabled; // Designated Initializer
- (instancetype)initWithImageNamedNormal:(NSString *)normal selected:(NSString *)selected;
- (instancetype)initWithImageNamedNormal:(NSString *)normal selected:(NSString *)selected disabled:(NSString *)disabled;
/** Sets the target-action pair, that is called when the Button is tapped.
"target" won't be retained.
*/
- (void)setTouchUpInsideTarget:(id)target action:(SEL)action;
- (void)setTouchDownTarget:(id)target action:(SEL)action;
- (void)setTouchUpTarget:(id)target action:(SEL)action;
@end
实施
//
//
// Courtesy of Graf on Stack Overflow
//
//
//
#import "SKBButtonNode.h"
@implementation SKBButtonNode
#pragma mark Texture Initializer
/**
* Override the super-classes designated initializer, to get a properly set SKButton in every case
*/
- (instancetype)initWithTexture:(SKTexture *)texture color:(UIColor *)color size:(CGSize)size {
return [self initWithTextureNormal:texture selected:nil disabled:nil];
}
- (instancetype)initWithTextureNormal:(SKTexture *)normal selected:(SKTexture *)selected {
return [self initWithTextureNormal:normal selected:selected disabled:nil];
}
/**
* This is the designated Initializer
*/
- (instancetype)initWithTextureNormal:(SKTexture *)normal selected:(SKTexture *)selected disabled:(SKTexture *)disabled {
self = [super initWithTexture:normal color:[UIColor whiteColor] size:normal.size];
if (self) {
[self setNormalTexture:normal];
[self setSelectedTexture:selected];
[self setDisabledTexture:disabled];
[self setIsEnabled:YES];
[self setIsSelected:NO];
_title = [SKLabelNode labelNodeWithFontNamed:@"Arial"];
[_title setVerticalAlignmentMode:SKLabelVerticalAlignmentModeCenter];
[_title setHorizontalAlignmentMode:SKLabelHorizontalAlignmentModeCenter];
[self addChild:_title];
[self setUserInteractionEnabled:YES];
}
return self;
}
#pragma mark Image Initializer
- (instancetype)initWithImageNamedNormal:(NSString *)normal selected:(NSString *)selected {
return [self initWithImageNamedNormal:normal selected:selected disabled:nil];
}
- (instancetype)initWithImageNamedNormal:(NSString *)normal selected:(NSString *)selected disabled:(NSString *)disabled {
SKTexture *textureNormal = nil;
if (normal) {
textureNormal = [SKTexture textureWithImageNamed:normal];
}
SKTexture *textureSelected = nil;
if (selected) {
textureSelected = [SKTexture textureWithImageNamed:selected];
}
SKTexture *textureDisabled = nil;
if (disabled) {
textureDisabled = [SKTexture textureWithImageNamed:disabled];
}
return [self initWithTextureNormal:textureNormal selected:textureSelected disabled:textureDisabled];
}
#pragma -
#pragma mark Setting Target-Action pairs
- (void)setTouchUpInsideTarget:(id)target action:(SEL)action {
_targetTouchUpInside = target;
_actionTouchUpInside = action;
}
- (void)setTouchDownTarget:(id)target action:(SEL)action {
_targetTouchDown = target;
_actionTouchDown = action;
}
- (void)setTouchUpTarget:(id)target action:(SEL)action {
_targetTouchUp = target;
_actionTouchUp = action;
}
#pragma -
#pragma mark Setter overrides
- (void)setIsEnabled:(BOOL)isEnabled {
_isEnabled = isEnabled;
if ([self disabledTexture]) {
if (!_isEnabled) {
[self setTexture:_disabledTexture];
} else {
[self setTexture:_normalTexture];
}
}
}
- (void)setIsSelected:(BOOL)isSelected {
_isSelected = isSelected;
if ([self selectedTexture] && [self isEnabled]) {
if (_isSelected) {
[self setTexture:_selectedTexture];
} else {
[self setTexture:_normalTexture];
}
}
}
#pragma -
#pragma mark Touch Handling
/**
* This method only occurs, if the touch was inside this node. Furthermore if
* the Button is enabled, the texture should change to "selectedTexture".
*/
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
if ([self isEnabled]) {
if (_actionTouchDown){
[self.parent performSelectorOnMainThread:_actionTouchDown withObject:_targetTouchDown waitUntilDone:YES];
[self setIsSelected:YES];
}
}
}
/**
* If the Button is enabled: This method looks, where the touch was moved to.
* If the touch moves outside of the button, the isSelected property is restored
* to NO and the texture changes to "normalTexture".
*/
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
if ([self isEnabled]) {
UITouch *touch = [touches anyObject];
CGPoint touchPoint = [touch locationInNode:self.parent];
if (CGRectContainsPoint(self.frame, touchPoint)) {
[self setIsSelected:YES];
} else {
[self setIsSelected:NO];
}
}
}
/**
* If the Button is enabled AND the touch ended in the buttons frame, the
* selector of the target is run.
*/
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint touchPoint = [touch locationInNode:self.parent];
if ([self isEnabled] && CGRectContainsPoint(self.frame, touchPoint)) {
if (_actionTouchUpInside){
[self.parent performSelectorOnMainThread:_actionTouchUpInside withObject:_targetTouchUpInside waitUntilDone:YES];
}
}
[self setIsSelected:NO];
if (_actionTouchUp){
[self.parent performSelectorOnMainThread:_actionTouchUp withObject:_targetTouchUp waitUntilDone:YES];
}
}
@end