前景ビューと背景ビュー、および UIPanGestureRecognizer を備えた UITableViewCell サブクラスを使用します。このレコグナイザーはスワイプをトリガーし、フォアグラウンド ビューの移動を処理します。
とはいえ、ここで実装を見つけることができます: https://github.com/spiilliams/sparrowlike
重要なビット:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"CustomCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
// Configure the cell...
UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePan:)];
[panGestureRecognizer setDelegate:self];
[cell addGestureRecognizer:panGestureRecognizer];
return cell;
}
#pragma mark - Gesture recognizer delegate
- (BOOL)gestureRecognizerShouldBegin:(UIPanGestureRecognizer *)panGestureRecognizer
{
CustomCell *cell = (CustomCell *)[panGestureRecognizer view];
CGPoint translation = [panGestureRecognizer translationInView:[cell superview] ];
return (fabs(translation.x) / fabs(translation.y) > 1) ? YES : NO;
}
#pragma mark - Gesture handlers
-(void)handlePan:(UIPanGestureRecognizer *)panGestureRecognizer
{
float threshold = (PAN_OPEN_X+PAN_CLOSED_X)/2.0;
float vX = 0.0;
float compare;
NSIndexPath *indexPath = [self.tableView indexPathForCell:(CustomCell *)[panGestureRecognizer view] ];
UIView *view = ((CustomCell *)panGestureRecognizer.view).frontView;
switch ([panGestureRecognizer state]) {
case UIGestureRecognizerStateBegan:
if (self.openCellIndexPath.section != indexPath.section || self.openCellIndexPath.row != indexPath.row) {
[self snapView:((CustomCell *)[self.tableView cellForRowAtIndexPath:self.openCellIndexPath]).frontView toX:PAN_CLOSED_X animated:YES];
[self setOpenCellIndexPath:nil];
[self setOpenCellLastTX:0];
}
break;
case UIGestureRecognizerStateEnded:
vX = (FAST_ANIMATION_DURATION/2.0)*[panGestureRecognizer velocityInView:self.view].x;
compare = view.transform.tx + vX;
if (compare > threshold) {
[self snapView:view toX:PAN_CLOSED_X animated:YES];
[self setOpenCellIndexPath:nil];
[self setOpenCellLastTX:0];
} else {
[self snapView:view toX:PAN_OPEN_X animated:YES];
[self setOpenCellIndexPath:[self.tableView indexPathForCell:(CustomCell *)panGestureRecognizer.view] ];
[self setOpenCellLastTX:view.transform.tx];
}
break;
case UIGestureRecognizerStateChanged:
compare = self.openCellLastTX+[panGestureRecognizer translationInView:self.view].x;
if (compare > PAN_CLOSED_X)
compare = PAN_CLOSED_X;
else if (compare < PAN_OPEN_X)
compare = PAN_OPEN_X;
[view setTransform:CGAffineTransformMakeTranslation(compare, 0)];
break;
default:
break;
}
}
-(void)snapView:(UIView *)view toX:(float)x animated:(BOOL)animated
{
if (animated) {
[UIView beginAnimations:nil context:nil];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
[UIView setAnimationDuration:FAST_ANIMATION_DURATION];
}
[view setTransform:CGAffineTransformMakeTranslation(x, 0)];
if (animated) {
[UIView commitAnimations];
}
}