How To Get IndexPath from NSDictionary - ios

Question

Imagine I have the following NSDictionary
dict = {
"a" = [
obj1,
obj2,
obj3
],
"b" = [
obj4,
obj5
],
"invalid" = [
obj6,
obj7,
obj8
],
"c" = [
obj9,
obj10,
obj11
]
}
This data is used to populate a TableView using sections from the following NSArray:
arr = #[#"A", #"B", #"C", #"D", #"E", #"F", #"G", #"H", #"I", #"J", #"K", #"L", #"M", #"N", #"O", #"P", #"Q", #"R", #"S", #"T", #"U", #"V", #"W", #"X", #"Y", #"Z"];
I have the following method which I use to find an object
- (void)selectRowWithId:(NSNumber *)uid {
[dict enumerateKeysAndObjectsUsingBlock:^(id _Nonnull key, id _Nonnull obj, BOOL * _Nonnull stop) {
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"(id == %#)", uid];
NSArray *filteredDictArray = [obj filteredArrayUsingPredicate:predicate];
if ([filteredDictArray count] > 0) {
NSIndexPath *targetIndexPath = nil;
//trying to find the NSIndexPath here
[[self tableView] selectRowAtIndexPath:targetIndexPath animated:NO scrollPosition:UITableViewScrollPositionMiddle];
[self tableView:[self tableView] didSelectRowAtIndexPath:targetIndexPath];
}
}];
}
Say I have an object set to obj10.
Based on my NSDictionary and NSArray the NSIndexPath is Section:2 Row:1
How can I get this value if I only know obj10?
Update (Solution)
So With a combination of the ideas behind everyone's answers and my own here is the following I used in case it's helpful for someone. BTW: This is for iOS9
- (void)selectRowWithId:(NSNumber *)uid {
[dict enumerateKeysAndObjectsUsingBlock:^(id _Nonnull key, id _Nonnull obj, BOOL * _Nonnull stop) {
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"(id == %#)", uid];
NSArray *filteredDictArray = [obj filteredArrayUsingPredicate:predicate];
if ([filteredDictArray count] > 0) {
//trying to find the NSIndexPath here
NSIndexPath *targetIndexPath = [NSIndexPath indexPathForRow:[[dict objectForKey:key] indexOfObject:filteredPersonsArray[0]] inSection:[arr indexOfObject:key]];
[[self tableView] selectRowAtIndexPath:targetIndexPath animated:NO scrollPosition:UITableViewScrollPositionMiddle];
[self tableView:[self tableView] didSelectRowAtIndexPath:targetIndexPath];
}
}];
}

Answer 1

Your code is a little bit too tricky. Sometimes usual looping is easier.
[dict enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL * stop)
{
for( NSInteger index = 0; index < [obj count]; index++ )
{
if ([obj[index] isEqualToString:uid])
{
// thats the index
// Let's have a look-up for the section
NSString *sectionKey = [[key substringToIndex:1] uppercaseString]; //Typo
for( NSInteger section=0; section < [arr count]; section++ )
{
if( [arr[section] isEqualToString:sectionKey] )
{
// That's the section
}
}
}
}
}
Typed in Safari.