iOS一次檢測到多個觸摸

Question

我正在創建一個遊戲，並且當前如果您觸摸屏幕的左半邊，則槍會順時針旋轉，如果觸摸屏幕的右半邊，則會進行拍攝。

我想創建一個動作，以便如果我觸摸屏幕的左半部分，它將順時針旋轉，如果您觸摸右半部分則逆時針旋轉。這很容易。

如果我在同一時間觸摸左右兩側，我想要拍攝。這怎麼可能同時檢測2個觸摸。

這是因爲，如果觸摸的右半

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { 
    UITouch *touch = [touches anyObject]; 
    CGPoint touchPoint = [touch locationInView:self.view]; 

    if (touchPoint.x < self.size.width/2.0) { 
     isTouching = true; 
    } 
    else 
     [self setupBullet]; 
} 

當觸摸左半邊和拍攝順時針旋轉代碼

Answer 1

你要麼需要設置兩個不同的對象，在他們各自的側面觸摸事件收聽，或您可以使用event.allTouches對象並獲取當前所有觸摸對象的完整陣列，並按照您的意願處理該陣列。

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { 
    //either: 
    if(touch in left side) 
    { 
     //Left side touch down, create object 
    } 
    else 
    { 
     //Right side touch down, create object 
    } 

    //Or: 
    NSArray *arrayOfAllTouches = event.allTouches; 
    //Now loop through that array and see what is going on on screen 
} 

-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { 
    //either: 
    if(touch in left side) 
    { 
     //Left side release, release object 
    } 
    else 
    { 
     //Right side release, release object 
    } 

    //Or: 
    NSArray *arrayOfAllTouches = event.allTouches; 
    //Now loop through that array and see what is going on on screen 
}