Here is my problematique: I design my cell in my UItableView, so I added a title, a little description and an image.
All thoses element are store in my database, so in my UIViewController I calculate every position to have a nice cell, if there is no image in a cell I change the position of the title and the little description.
To check if the image is present or not I do something like that:
if ([fiche linkImg]!=#"") { //draw position of element }
or
if ([fiche.linkImg length] > 0 ) { //draw position of element }
My problem is when I begin to slide in my tableview its very slow and often very often crash, and the error are sometimes:
[CALayerArray listImg]
or
[NSCFArray listImg]:
Any idea?
Your description is a tiny bit confusing to see what is the problem.
I would suggest having a look at how to accomplish adding custom stuff to cell.
Have a read of apple's doc on UITableView especially a closer look at Table-View cells, if you scroll down in that section you will find examples of exactly the type of cells you are trying to create (text with pictures).
Try adding like this
if([fiche linkImg]!=nil)
I tried and succeeded
Related
When creating a UITableViewController there are two situations that create an "ugly" UX
calling/open it without any data in it --> shows an empty table (i.e. empty rows,UITableViewCell, as many as fit in the window)
calling/open it with fewer rows of content that fit the window --> show the full rows followed by empty rows
I wish to receive the following result:
if there is no data show a picture or view with text - there isn't any data yet or something like that
show only the full lines and no more rows (blank or background image)
Is there a way to achieve that?
To add these effects, you will probably have to make your own UITableViewController from a regular UIViewController, and even subclass UITableView. If you have a regular UIViewController with your filler image/text as the background, you can place a UITableView on top and hook up the delegate/datasource. Now, in your code, detect when there is no data available and set the hidden property of the UITableView accordingly.
As for the following empty rows, you will either have to turn off the row separators (in IB), or subclass a UITableView (can't help you there). Good luck!
I have a weird design case in which to implement I need to place two UITableViews on the same view. I would just use sections, but I need an index on the second table.
I'd like them to both scroll together like they were actually two sections of the same table view. Is this possible?
Here's a basic mockup illustrating why:
As far as I understand it, you cannot move the index. Also, when you add an index to a table, it appears over the entire tableview, not just one section.
If I have to implement this as two table views, they both need to scroll as if they were one. If it's possible to do this using sections, that's even better.
Update
After seeing your update my old answer is not very good but I'll leave my previous answer for anyone else who wants it.
New answer - It depends how you want the tables sync'd.
If you know
Which cells are in the top 5
How tall each cell is
The offset the table view
Then you can calculate which cell is visible at the top of the top 5 table. You can use this information to scroll the bottom table to the correct index.
Old answer
I'm with the other guys not sure why you would want to or if I am misinterpreting but it's pretty simple.
UITableView is a subclass of UIScrollView so you can set yourself as the UITableViewDelegate and override
- (void)scrollViewDidScroll:(UIScrollView *)scrollView;
{
UITableView *slaveTable = nil;
if (self.table1 == scrollView) {
slaveTable = self.table2;
} else if (self.table2 == scrollView) {
slaveTable = self.table1;
}
[slaveTable setContentOffset:scrollView.contentOffset];
}
This gives me something that looks like this:
The top UITableView is self.table1 and the bottom is self.table2 if either table is scrolled the scrolling is mirrored in the other table.
in swift this code:
func scrollViewDidScroll(scrollView: UIScrollView) {
if tb_time1 == scrollView {
tb_time2.contentOffset = tb_time1.contentOffset
}else if tb_time2 == scrollView {
tb_time1.contentOffset = tb_time2.contentOffset
}
}
From the mock-up it seems like this can be accomplished with a single UITableView with two sections.
Instead of maintaining two tableViews you could maintain two collections (one for each section). Then in cellForRowAtIndexPath choose the collection to use based on the section specified in the indexPath.
Is there any way to change something about a table cell on the iPhone based on the previous or next table cell before that cell is displayed? This might be confusing, so here's an example:
Let's say I have a table like this (I'm just going to fill it with random values, so don't worry about the text contained in the cells):
*Cat
*Rabbit
*Dog
*Mouse
and there was a imageView.image attached to some cells (different images for different animals and you don't know which ones might have images) and at some point (programmatically) new animals are entered into the list sandwiching the animals that are already entered like so:
*[animal]
*Cat
*[animal]
*Rabbit
*[animal]
*Dog
*[animal]
*Mouse
*[animal]
How would I go about moving the images associated with the previously listed animals?
Hopefully you get a kick out of how ridiculous this question sounds, but I swear it is a serious question that is driving me insane and I didn't know how else to describe it.
Felixs' answer probably works, but it sounds like you are thinking of it from view-manipulation angle, and not a model-manipulation angle. It sounds like you really have two parallel models: the list of animals and the set of images. Why not just reloadData when either thing changes and rebuild the cells appropriately from inside your controller?
Reaching into existing cells based on their index feels fragile to me.
I hope I've got the right end of the stick here, but: In the cellForRowAtIndexPath: method, you could get a pointer to the previous cell (and so any associated images, text, etc.):
NSIndexPath *indexPathForPreviousCell=[NSIndexPath indexPathForRow:indexPath.row+1 inSection:indexPath.section];
UITableViewCell *previousCell=[tableView cellForRowAtIndexPath:indexPathForPreviousCell];
I hope this is what you needed...
I'd like to add section headers to my grouped table view's sections but I'd like them to appear seamless (see image). The default, as we're all well aware of, is rounded top corners on the first row of a grouped table view cell so it ends up looking like crap when you merge them.
Any way to specify when indexPath.row = 0 that the UITableViewCell should use row style "middle" or something like that?
If not then what are my options? I guess I could scratch the section header and use Row 0 as a quasi-header then push my array data +1 to fill the rest of the table? I'd rather not roll my own from scratch...if possible.
Sample Table http://img35.imageshack.us/img35/8181/sampletable.png
Edit:
"Crap" looks like this:
alt text http://img25.imageshack.us/img25/9748/crapsection.png
Don't do what you're doing, it's against HIG
Ok, ok, I'll tell you how to do it:
You're going to want to do your own cell background views. The default grouped one is not what you want.
When a tableview asks you for a cell, set its backgroundView and selectedBackgroundView to something that looks appropriate for its place in the tableview.
Usually, this means a UIImageView with the appropriate image, though you can go wild here with a custom view, but there are gotchas.
So in your case, you would do
if (indexPath.row > sectionRowCount - 1) {
//Not the last row
//Put in the middle background
} else {
//Put in the end background
}
Then you'll want a custom table section header, but that's pretty easy.
In your case, you probably won't have to worry about when there's just one row, so that makes things even easier.
Take a look at the tutorial here:
cocoa with love basically what you need is 3 different images. One for the top row, one for the bottom, and a 3rd for the middle rows.
You could also not use the section header, but instead use a custom cell as the first cell of the section. So when ([indexPath row] == 0), return a custom cell that is the "header" and then return the "regular" cells (offset by one row) for the rest. You'll also have to make adjustments to the numberOfRowsInSection function to return +1.
I have a UITableView with some empty sections. I'd like the user to be able to move a row into them using the standard edit mode controls. The only way I can do it so far is to have a dummy row in my "empty" sections and try to hide it by using tableView:heightForRowAtIndexPath: to give the dummy row a height of zero. This seems to leave it as a 1-pixel row. I can probably hide this by making a special type of cell that's just filled with [UIColor groupTableViewBackgroundColor], but is there a better way?
This is all in the grouped mode of UITableView.
UPDATE: Looks like moving rows into empty sections is possible without any tricks, but the "sensitivity" is bad enough that you DO need tricks in order to make it usable for general users (who won't be patient enough to slowly hover the row around the empty section until things click).
I found that in iOS 4.3, the dummy row needs to have a height of at least 1 pixel in order to give the desired effect of allowing a row to be moved into that section.
I also found that the dummy row is only needed in the first and last section; any sections in between don't have this problem.
And it looks like in iOS 5.0, no dummy rows or special tricks are needed at all.
While managing the edit, you can monitor if the table view is in Edit Mode. Use that flag inside of cellForRowAtIndexPath to decide weather or not to display the 'blank' row. While in 'regular' mode, the row will not display, but when the user taps 'edit' cellForRowAtIndexPath should get called again and this time decide to display the row. The details of how to do that depend on your data source and how you are gluing it to the display. If you aren't getting the call again, you can manually inject rows with insertRowsAtIndexPaths / deleteRowsAtIndexPaths and/or call reloadData to force a refresh.
I found that if you return -1.0 from the heightForRowAtIndexPath method it will remove the 1 pixel line.