uitableview numberOfRowsInSection count - iphone

Question

This is more of a math problem than anything else. What I have is a dynamic array object in which I store user photos.
arryData = [[NSArray alloc] initWithObjects:#"pic1.png", #"pic2.png", #"pic3.png", #"pic4.png", #"pic5.png", #"pic6.png",#"pic7.png", #"pic8.png",nil];
This array can have any amount of objects in it e.g 8 or 20 or 100. In my table view I have created 4 UIImageViews per row by adding them to cell.contentview. So if lets say
if arryData has 3 objects then I want UITable to create 1 row
if arryData has 4 objects then I want UITable to create 1 row
if arryData has 5 objects then I want UITable to create 2 rows
if arryData has 8 objects then I want UITable to create 2 rows
if arryData has 10 objects then I want UITable to create 3 rows
.... and so on
So how do I do this for N number of objects in my arryData?
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
//NSLog(#"Inside numberOfRowsInSection");
//return [arryData count];
//Cannot think of a logic to use here? I thought about dividing [arryData count]/4 but that will give me fractions
}
Picture is worth a thousand words.

Answer 1

So basically you need to divide by four, rounding up. Since integer division in Objective-C truncates (rounds toward zero), you can round up by doing this:
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return (arryData.count + 3) / 4;
}
In general, to make integer division (with positive integers) round up, you add the denominator-1 to the numerator before dividing.
If you have defined a constant for the number of images per row, use it. For example:
static const int kImagesPerRow = 4;
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return (arryData.count + kImagesPerRow - 1) / kImagesPerRow;
}

Answer 2

For the row count, divide by the number of images and round up:
rowCount = ceilf([arryData count] / 4.0);

Answer 3

I suppose you have only one section so:
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
NSInteger photoNumber = [yourDataSource count];
if(photoNumber % numberOfPhotosOnRow == 0) {
return photoNumber/numberOfPhotosOnRow;
}
else {
return photoNumber/numberOfPhotosOnRow + 1;
}
}

Answer 4

I had to create something similar for an application I wrote a little while back(it seems you want to include 4 images per cell)`
if (tableView == yourTableView)
{
int rows = [yourArray count];
int rowsToReturn = rows / 4;
int remainder = rows % 4;
if (rows == 0) {
return 0;
}
if (rowsToReturn >0)
{
if (remainder >0)
{
return rowsToReturn + 1;
}
return rowsToReturn ;
}
else
return 1;
}`