问题
I am using custom cell and headerView with static images and footerView but not scrolling as smoothly as it should scroll, it is getting stuck in middle and then scrolls........
Header
-(UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section{
UIView *headerview = [[UIView alloc]init];
if (section == 2) {
headerview.frame = CGRectMake(0, 30, tableView.frame.size.width, 117);
Button = [[UIButton alloc]initWithFrame:CGRectMake(0, 18, headerview.frame.size.width, 100)];
UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(5, 0, tableView.frame.size.width, 17)];
label.text = @"Siddharth and hiren Like this";
label.font = [UIFont systemFontOfSize:10];
label.textColor = [UIColor blackColor];
[headerview addSubview:label];
}
else
{
headerview.frame = CGRectMake(0, 0, tableView.frame.size.width, 100);
Button = [[UIButton alloc]initWithFrame:headerview.frame];
}
// sheap top left and top right
UIBezierPath *maskPath;
maskPath = [UIBezierPath bezierPathWithRoundedRect:headerview.bounds
byRoundingCorners:(UIRectCornerTopLeft|UIRectCornerTopRight)
cornerRadii:CGSizeMake(7.0, 7.0)];
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
headerview.frame = headerview.bounds;
maskLayer.path = maskPath.CGPath;
headerview.layer.mask = maskLayer;
// shape for button bottom
headerview.backgroundColor = [UIColor whiteColor];
CALayer *bottomBorder = [CALayer layer];
bottomBorder.frame = CGRectMake(0.0f, 0, headerview.frame.size.width, 1);
bottomBorder.backgroundColor = [UIColor colorWithRed:217/255.0f green:217/255.0f blue:217/255.0f alpha:1].CGColor;
bottomBorder.shadowColor = [[UIColor blackColor] CGColor];
bottomBorder.shadowOpacity = 0.9f;
bottomBorder.shadowRadius = 0.3f;
[headerview.layer addSublayer:bottomBorder];
headerview.layer.shouldRasterize = YES;
// Button Imageview
UIImageView *buttonimg = [[UIImageView alloc]initWithFrame:Button.bounds];
buttonimg.image = [UIImage imageNamed:[_SecImgArray objectAtIndex:section]];
buttonimg.layer.shouldRasterize = YES;
[Button addSubview:buttonimg];
// imageview overlay
UIView *overlay = [[UIView alloc]initWithFrame:Button.bounds];
overlay.alpha = 0.3;
overlay.backgroundColor = [UIColor blackColor];
overlay.layer.shouldRasterize = YES;
[buttonimg addSubview:overlay];
[Button addTarget:self action:@selector(Expand: and:) forControlEvents:UIControlEventTouchUpInside];
Button.tag = section;
if ([[AllNewsdic objectForKey:@"posts"] count] == 0) {
[Button setTitle:[[[DownloadData objectForKey:@"posts"]objectAtIndex:section]objectForKey:@"title"] forState:UIControlStateNormal];
}
else
{
[Button setTitle:[[[AllNewsdic objectForKey:@"posts"]objectAtIndex:section]objectForKey:@"title"] forState:UIControlStateNormal];
}
[Button setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
Button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;
Button.contentVerticalAlignment = UIControlContentVerticalAlignmentBottom;
Button.contentEdgeInsets = UIEdgeInsetsMake(0, 10, 0, 0);
Button.titleLabel.lineBreakMode = NSLineBreakByWordWrapping;
Button.titleLabel.numberOfLines = 0;
Button.titleLabel.font = [UIFont fontWithName:@"Avenir-Black" size:12];
Button.layer.shadowColor = [UIColor greenColor].CGColor;
Button.layer.shadowOpacity = 0.4;
Button.layer.shadowRadius = 1.0f;
Button.layer.cornerRadius = 7;
Button.layer.masksToBounds = YES;
Button.layer.shouldRasterize = YES;
[headerview addSubview:Button];
return headerview;}
Footer
-(UIView *)tableView:(UITableView *)tableView viewForFooterInSection:(NSInteger)section{
UIView *fotter = [[UIView alloc]initWithFrame:CGRectMake(0, -10, tableView.frame.size.width, 30)];
fotter.backgroundColor = [UIColor whiteColor];
// corner redius
UIBezierPath *maskPath;
maskPath = [UIBezierPath bezierPathWithRoundedRect:fotter.bounds
byRoundingCorners:(UIRectCornerBottomLeft|UIRectCornerBottomRight)
cornerRadii:CGSizeMake(7.0, 7.0)];
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
fotter.frame = fotter.bounds;
maskLayer.path = maskPath.CGPath;
// maskLayer.backgroundColor = [UIColor colorWithRed:217/255.0f green:217/255.0f blue:217/255.0f alpha:1].CGColor;
fotter.layer.mask = maskLayer;
// Bottom layer
CALayer *bottomBorder = [CALayer layer];
bottomBorder.frame = CGRectMake(0.0f, 32, fotter.frame.size.width, 2);
bottomBorder.backgroundColor = [UIColor blackColor].CGColor;
[fotter.layer addSublayer:bottomBorder];
// top Layer
CALayer *topLayer = [CALayer layer];
topLayer.frame = CGRectMake(13, 0, fotter.frame.size.width - 26, 0.7);
topLayer.backgroundColor = [UIColor colorWithRed:197/255.0f green:187/255.0f blue:188/255.0f alpha:1].CGColor;
topLayer.shadowOpacity = 0.6f;
topLayer.shadowRadius = 0.5f;
[fotter.layer addSublayer:topLayer];
// Like bUtton
likebutton = [[UIButton alloc]initWithFrame:CGRectMake(0, -3, fotter.frame.size.width/2, fotter.frame.size.height + 3)];
likebutton.titleLabel.font = [UIFont systemFontOfSize:10];
likebutton.titleLabel.tintColor = [UIColor colorWithRed:197/255.0f green:187/255.0f blue:188/255.0f alpha:1];
[likebutton addTarget:self action:@selector(like:) forControlEvents:UIControlEventTouchUpInside];
[likebutton setTitle:@"1 likes" forState:UIControlStateNormal];
likebutton.tag = section;
like = [[UIImageView alloc]initWithFrame:CGRectMake(40 ,8, 15, 15)];
like.image = [UIImage imageNamed:@"SimpleLike.png"];
[likebutton addSubview:like];
[likebutton setTitleColor:[UIColor grayColor] forState:UIControlStateNormal];
[fotter addSubview:likebutton];
// Follow Button
NSLog(@"%f",fotter.frame.size.width/2 + 1);
follow = [[UIButton alloc]initWithFrame:CGRectMake(fotter.frame.size.width/2 , -3, fotter.frame.size.width/2, fotter.frame.size.height + 3)];
follow.titleLabel.font = [UIFont systemFontOfSize:10];
follow.titleLabel.tintColor = [UIColor colorWithRed:197/255.0f green:187/255.0f blue:188/255.0f alpha:1];
[follow setTitle:@"Follow" forState:UIControlStateNormal];
followimage = [[UIImageView alloc]initWithFrame:CGRectMake(35 ,8, 17, 17)];
followimage.image = [UIImage imageNamed:@"Follow.png"];
[follow addSubview:followimage];
[follow setTitleColor:[UIColor grayColor] forState:UIControlStateNormal];
follow.tag = section;
[follow addTarget:self action:@selector(Follow:) forControlEvents:UIControlEventTouchUpInside];
[fotter addSubview:follow];
return fotter;}
Cell
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
AllNewsTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"AllNews"];
cell.one.text = [one objectAtIndex:indexPath.section];
cell.two.text = [two objectAtIndex:indexPath.section];
cell.three.text = [three objectAtIndex:indexPath.section];
[cell.three sizeToFit];
return cell;}
how to set tableview scroll smooth and effective how to set interface properties tableview data is static
回答1:
Use reusable UITableViewCell inside function viewForHeaderInSection and inside viewForFooterInSection Do not create the new UIView and buttons for each function call.
回答2:
Your table view scrolling is not smooth because the views inside viewForHeaderInSection and viewForFooterInSection methods are allocated multiple times. Why ? Because whenever you scroll up and down, both the methods are called as and when required.
Check whether header view is already allocated. If it is nil, then and then allocate it and return it. Otherwise, just return it. Same way in case of footer view.
Add comment in case of any doubt..
来源：https://stackoverflow.com/questions/34765218/tableview-not-scrolling-smooth-with-static-data