UITouch觸摸操作

1. 觸摸操作的生命周期

  • 手指觸摸屏幕的瞬間
    在這個(gè)過(guò)程中，可以通過(guò) touch.tapCount 判斷是單擊還是雙擊。
    可以通過(guò) [touch locationInView:self.view] 來(lái)獲取點(diǎn)擊位置坐標(biāo)
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Heiti SC Light'; color: #008400}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #d12f1b}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}span.s1 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures}span.s3 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s4 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s5 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s6 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s7 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures}span.s8 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures; color: #000000}span.s9 {font-variant-ligatures: no-common-ligatures; color: #272ad8}span.s10 {font-variant-ligatures: no-common-ligatures; color: #d12f1b}span.s11 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures; color: #d12f1b}span.s12 {font-variant-ligatures: no-common-ligatures; color: #4f8187}

//當(dāng)點(diǎn)擊屏幕開始的瞬間，調(diào)用此函數(shù)，即狀態(tài)1
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    NSLog(@"手指觸碰瞬間");
    //獲取點(diǎn)擊對(duì)象。anyObeject獲取任何一個(gè)點(diǎn)擊對(duì)象
    //一般只有一個(gè)點(diǎn)擊對(duì)象
    UITouch* touch=[touches anyObject];
    
    
    //記錄點(diǎn)擊的次數(shù)
    
    if(touch.tapCount==1)
        NSLog(@"單次點(diǎn)擊");
    else if (touch.tapCount==2)
        NSLog(@"雙擊");
    
}
  • 手指在屏幕上未離開過(guò)程
    在這個(gè)過(guò)程中可以通過(guò) [touch locationInView: ]來(lái)獲取手指相對(duì)于當(dāng)前視圖的坐標(biāo)。
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Heiti SC Light'; color: #d12f1b}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Heiti SC Light'; color: #008400}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s3 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s4 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures; color: #000000}span.s5 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s6 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s7 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    NSLog(@"手指在屏幕上, 并且移動(dòng)。可以獲取坐標(biāo)數(shù)據(jù)");
    
    //獲取手指相對(duì)當(dāng)前視圖的坐標(biāo)
    UITouch* touch=[touches anyObject];
    CGPoint pt=[touch locationInView:self.view];
  • 手指離開屏幕的瞬間
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #d12f1b}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s3 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s4 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s5 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s6 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures}

-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
    NSLog(@"手指離開屏幕");
}
  • 還有一個(gè)特殊情況下終止觸屏操作的協(xié)議，比如游戲過(guò)程中來(lái)電話
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #d12f1b}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s3 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s4 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s5 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s6 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures}

-(void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
    NSLog(@"特殊情況下終端觸屏.比如電話");
}

2.實(shí)現(xiàn)手指拖拽控制圖片移動(dòng)的功能

手指移動(dòng)的偏移量決定圖片移動(dòng)的向量，所以需要計(jì)算此時(shí)手指坐標(biāo)和上一時(shí)刻手指坐標(biāo)的差值。

在ViewController.h中聲明一個(gè)CGPoint，用來(lái)存放上一時(shí)刻手指位置：

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}span.s1 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s2 {font-variant-ligatures: no-common-ligatures}

CGPoint _mPtList;

然后獲得此時(shí)手指位置并計(jì)算偏移量大小：
注意 計(jì)算完要把此時(shí)的位置賦給 _mPtList

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Heiti SC Light'; color: #008400}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #4f8187}span.s1 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures; color: #000000}span.s2 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s3 {font-variant-ligatures: no-common-ligatures}span.s4 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s5 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s6 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s7 {font-variant-ligatures: no-common-ligatures; color: #4f8187}span.s8 {font-variant-ligatures: no-common-ligatures; color: #000000}

    //獲取手指相對(duì)當(dāng)前視圖的坐標(biāo)
    UITouch* touch=[touches anyObject];
    CGPoint pt=[touch locationInView:self.view];
    
    //每次移動(dòng)偏移量大小
    float xOffset=pt.x-_mPtList.x;
    float yOffset=pt.y-_mPtList.y;
    
    _mPtList=pt;

然后根據(jù)偏移量改變圖像視圖的位置：

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s3 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s4 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s5 {font-variant-ligatures: no-common-ligatures; color: #272ad8}span.s6 {font-variant-ligatures: no-common-ligatures; color: #d12f1b}

    UIImageView* iView=[self.view viewWithTag:101];
    
    NSLog(@"x=%f,y=%f",pt.x,pt.y);
    
    iView.frame=CGRectMake(iView.frame.origin.x+xOffset, iView.frame.origin.y+yOffset, iView.frame.size.width, iView.frame.size.height);
最后編輯于 ：
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