Removes the indexes in an index range from the receiver.
- (void)removeIndexesInRange:(NSRange)indexRange
Parameters of [NSMutableIndexSet removeIndexesInRange]
indexRange
Index range to remove.
NSMutableIndexSet removeIndexesInRange example.
You may want to look at NSMutableIndexSet. It is designed to efficiently store ranges of numbers.
You can initialize it like this:
NSMutableIndexSet *set = [[NSMutableIndexSet alloc]
initWithIndexesInRange:NSMakeRange(1, 100000)];
Then you can remove, for example, 123 from it like this:
[set removeIndex:123];
Or you can remove 400 through 409 like this:
[set removeIndexesInRange:NSMakeRange(400, 10)];
You can iterate through all of the remaining indexes in the set like this:
[set enumerateIndexesUsingBlock:^(NSUInteger i, BOOL *stop) {
NSLog(@"set still includes %lu", (unsigned long)i);
}];
or, more efficiently, like this:
[set enumerateRangesUsingBlock:^(NSRange range, BOOL *stop) {
NSLog(@"set still includes %lu indexes starting at %lu",
(unsigned long)range.length, (unsigned long)range.location);
}];
Removes the indexes in an index set from the receiver.
- (void)removeIndexes:(NSIndexSet *)indexSet
Parameters of [NSMutableIndexSet removeIndexes]
indexSet
Index set to remove.
NSMutableIndexSet removeIndexes example.
You may want to look at NSMutableIndexSet. It is designed to efficiently store ranges of numbers.
You can initialize it like this:
NSMutableIndexSet *set = [[NSMutableIndexSet alloc]
initWithIndexesInRange:NSMakeRange(1, 100000)];
Then you can remove, for example, 123 from it like this:
[set removeIndex:123];
Or you can remove 400 through 409 like this:
[set removeIndexesInRange:NSMakeRange(400, 10)];
You can iterate through all of the remaining indexes in the set like this:
[set enumerateIndexesUsingBlock:^(NSUInteger i, BOOL *stop) {
NSLog(@"set still includes %lu", (unsigned long)i);
}];
or, more efficiently, like this:
[set enumerateRangesUsingBlock:^(NSRange range, BOOL *stop) {
NSLog(@"set still includes %lu indexes starting at %lu",
(unsigned long)range.length, (unsigned long)range.location);
}];
Parameters of [NSMutableIndexSet removeIndex]
index
Index to remove.
NSMutableIndexSet removeIndex example.
You may want to look at NSMutableIndexSet. It is designed to efficiently store ranges of numbers.
You can initialize it like this:
NSMutableIndexSet *set = [[NSMutableIndexSet alloc]
initWithIndexesInRange:NSMakeRange(1, 100000)];
Then you can remove, for example, 123 from it like this:
[set removeIndex:123];
Or you can remove 400 through 409 like this:
[set removeIndexesInRange:NSMakeRange(400, 10)];
You can iterate through all of the remaining indexes in the set like this:
[set enumerateIndexesUsingBlock:^(NSUInteger i, BOOL *stop) {
NSLog(@"set still includes %lu", (unsigned long)i);
}];
or, more efficiently, like this:
[set enumerateRangesUsingBlock:^(NSRange range, BOOL *stop) {
NSLog(@"set still includes %lu indexes starting at %lu",
(unsigned long)range.length, (unsigned long)range.location);
}];
Example of [NSMutableIndexSet removeIndex].
- (NSUInteger)indexForImageGivenIndexSet:(NSIndexSet*)indexSet // Set of indexes you want to select from
prizeImageIndex:(NSUInteger)prizeIndex // The prize index
probabilityScale:(CGFloat)probabilityScale // The scale for the prize (8.0 for 8x less than the others)
{
// If invalid, return what was given
if (![indexSet containsIndex:prizeIndex]) {
return prizeIndex;
}
// Calculate our probabilities
// For a set of 4, with a scale of 8 on the prize, our probabilities would be
// 0.04 (prize), 0.32, 0.32, 0.32
double prizeProbability = (1.0 / indexSet.count) * (1.0 / probabilityScale);
double val = (double)arc4random() / RAND_MAX;
if (val < prizeProbability) {
return prizeIndex;
}
else {
// Select from the others in range equally
NSMutableIndexSet* newSet = [[NSMutableIndexSet alloc] initWithIndexSet:indexSet];
[newSet removeIndex:prizeIndex];
You will have to make subclass of the NSTableView class. This is basic example how you could do it. It handles selection with the spacebar and with the right mouse button, hoever it does not handle right mouse button drag selection.
The idea is to use NSTableView in single select mode and implement alternative selection. We add property markedRows and then use it instead of original selectedRows property.
//Not tested
//Assume that selectedIndexes is a NSMutableIndexSet
if ([selectedIndexes containsIndex:indexPath.row]) {
if (self.options.count) {//This could probably be optimised depend on your goal
[selectedIndexes addIndexesInRange:NSMakeRange(0,self.options.count-1)];
} else {
[selectedIndexes removeAllIndexes];
}
}
NSMutableIndexSet removeAllIndexes example.
- (void)createFilteredTableGroups{
//Checking for the usual suspects. all which may through an exception
if(model==nil)
return;
if(tableGroups==nil)
return;
if([tableGroups count]==0)
return;
//lets make a new array to work with
NSMutableArray *newTableGroups = [[allTableGroups mutableCopy] autorelease];
//telling the table what we are about to do
[self.tableView beginUpdates];
//array to track cells for deletion animation
NSMutableArray *indexesToRemove = [NSMutableArray array];
//loop through each section
for(NSMutableArray *eachSection in tableGroups){
//keeping track of the indexes to delete for each section
NSMutableIndexSet *indexesForSection = [NSMutableIndexSet indexSet];
[indexesForSection removeAllIndexes];
//increment though cell indexes
int rowIndex = 0;
//loop through each cellController in the section
for(ScheduleCellController *eachCellController in eachSection){
//Ah ha! A little magic. the cell controller must know if it should be displayed.
//This you must calculate in your business logic
if(![eachCellController shouldDisplay]){
}
rowIndex++;
}
//adding each array of section indexes, EVEN if it is empty (no indexes to delete)
[indexesToRemove addObject:indexesForSection];
}
//Now we remove cell controllers in newTableGroups and cells from the table
//Also, each subarray of newTableGroups is mutable as well
if([indexesToRemove count]>0){
int sectionIndex = 0;
for(NSMutableIndexSet *eachSectionIndexes in indexesToRemove){
//Now you know why we stuck the indexes into individual arrays, easy array method
[[newTableGroups objectAtIndex:sectionIndex] removeObjectsAtIndexes:eachSectionIndexes];
//tracking which cell indexPaths to remove for each section
NSMutableArray *indexPathsToRemove = [NSMutableArray array];
int numberOfIndexes = [eachSectionIndexes count];
//create array of indexPaths to remove
NSUInteger index = [eachSectionIndexes firstIndex];
for(int i = 0; i< numberOfIndexes; i++){
//delete the rows for this section
[self.tableView deleteRowsAtIndexPaths:indexPathsToRemove withRowAnimation:UITableViewRowAnimationTop];
//next section please
sectionIndex++;
}
}
//now we figure out if we need to remove any sections
NSMutableIndexSet *sectionsToRemove = [NSMutableIndexSet indexSet];
[sectionsToRemove removeAllIndexes];
int sectionsIndex = 0;
for(NSArray *eachSection in newTableGroups){
//checking for empty sections
if([eachSection count]==0)
[sectionsToRemove addIndex:sectionsIndex];
sectionsIndex++;
}
//updating the table groups
[newTableGroups removeObjectsAtIndexes:sectionsToRemove];
//removing the empty sections
[self.tableView deleteSections:sectionsToRemove withRowAnimation:UITableViewRowAnimationTop];
//updating filteredTableGroups to the newTableGroups we just created
self.filteredTableGroups = newTableGroups;
//pointing tableGroups at the filteredGroups
tableGroups = filteredTableGroups;
//invokes the animation
[self.tableView endUpdates];
Adds the indexes in an index range to the receiver.
- (void)addIndexesInRange:(NSRange)indexRange
Parameters
indexRange
Index range to add. Must include only indexes representable as unsigned integers.
Discussion of [NSMutableIndexSet addIndexesInRange]
This method raises an NSRangeException when indexRange would add an index that exceeds the maximum allowed value for unsigned integers.
NSMutableIndexSet addIndexesInRange example.
//Not tested
//Assume that selectedIndexes is a NSMutableIndexSet
if ([selectedIndexes containsIndex:indexPath.row]) {
if (self.options.count) {//This could probably be optimised depend on your goal
[selectedIndexes addIndexesInRange:NSMakeRange(0,self.options.count-1)];
} else {
[selectedIndexes removeAllIndexes];
}
}
Example of [NSMutableIndexSet addIndexesInRange].
@autoreleasepool {
// insert code here...
NSLog(@"Hello, World!");
NSRange indexRange = NSMakeRange(0, 6);
NSMutableIndexSet *newIndexSet = [[NSMutableIndexSet alloc] initWithIndexesInRange:indexRange];
for (int i=0; i<40; i++)
{
NSUInteger x = [newIndexSet oneTimeRandomIndex];
if (x == NSNotFound)
{
// NSLog(@"newIndexSet needs to be refilled");
[newIndexSet addIndexesInRange:indexRange];
x = [newIndexSet oneTimeRandomIndex];
}
switch (x) {
case 0:
NSLog(@"Cat");
break;
case 1:
NSLog(@"Dog");
break;
case 2:
NSLog(@"Fish");
break;
case 3:
NSLog(@"Horse");
break;
case 4:
NSLog(@"Bird");
break;
case 5:
NSLog(@"Wombat");
break;
default:
break;
}
Parameters of [NSMutableIndexSet addIndex]
index
Index to add.
NSMutableIndexSet addIndex example.
If the indexes are consecutive like in your example, you can use this:
NSIndexSet *indexSet = [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(1, 3)];
If not, create a mutable index set and add the indexes (or ranges) one by one:
// find the position of the highest amount of matches in the index set
NSUInteger highestIndex = indexOfMax;
returns = [results objectAtIndex:highestIndex];
NSMutableIndexSet addIndex example.
You can not enumerate and modify the NSMutableIndexSet you are enumerating. Just create a new NSMutableIndexSet and add the entries to it. It is doubtful that there is a performance hit.
