iOS swipe gesture Uipangesturerecognizer considerations

Today, when doing a slide-off page, it is found that the page slides with the swipe gesture, to the critical point, if the slide will appear jitter phenomenon. Finding a solution is to judge once before entering the method, and then deciding to slide the page within the sliding range. The slide gesture (Uipangesturerecognizer Note summarizes the following:

Code:

-(void) Panaction: (uipangesturerecognizer *) pan{

_canleft = YES;

_canright = YES;

position of//point relative to the previous point

cgpoint moviepoint = [pan translationinview:p an. View];

// point speed ( positive or negative to determine the sliding trend )

cgpoint velocity = [pan velocityinview:p an. View];

//Side -slip range

cgfloat instance = kscreenwidth - N;

// Prohibit left stroke ( at the far left )

if (pan. View. Left <= 0 && moviepoint. X <= 0) {

_canleft = NO;

}

// Prohibit right stroke ( at the far right )

if (pan. View. Left >= instance && moviepoint. X >= 0) {

_canright = NO;

}

// page can slide the condition

if (_canright && _canleft && pan. View. Left >= 0 && pan. View. Left <= instance) {

// mobile

Pan. View. Center =

cgpointmake(pan. View. Center. X + moviepoint. x, pan. View. Center. Y);

}

// reset required every time

[Pan settranslation:cgpointzero inview:p an. View];

// when releasing the finger, judge the sliding trend to return the position .

if (pan. state = = uigesturerecognizerstateended) {

if (pan. View. Left < ) {

Pan. View. Left = 0;

}Else if(pan. View. Left > Instance ) {

Pan. View. Left = instance;

}

       }

}

iOS swipe gesture Uipangesturerecognizer considerations