I have an array with a lot of empty values and I want to remove them from the array....
NSMutableArray *entry = [self.selectedRow allValues];
for (int i = 0 ; i < [entry count] ; i++) {
NSLog(#"count: %#", [entry objectAtIndex: i]);
NSLog(#"point: %#", [selectedRow valueForKey:[entry objectAtIndex:i]]);
if([[selectedRow valueForKey:[entry objectAtIndex: i]] length] < 2){
[selectedRow removeObjectAtIndex: i];
}
}
the < 2 is because there are some values there not really empty.....
for some reason [entry valueForKey:[entry objectAtIndex:i]]] is empty
and i get the exeption -[__NSCFDictionary removeObjectAtIndex:]: unrecognized selector sent to instance 0x7021510 but there is no dictionary involved ther are only arrays.
and when i count down for (int i = [entry count -1; i = 0; i--]){ the loop isn't even called?!?
I hope someone can help me with that....
EDIT:
Is not what initialy wanted but some how it works better that way...
I check the length for the valueForKey when I parse the file so i reduce the file size for more then the half and it works pretty good.....
Try this:
NSMutableArray *entry = [NSMutableArray arrayWithArray:[self.selectedRow allValues]];
because [self.selectedRow allValues] likely returns an NSArray you can't just pretend it's Mutable.
OH. and furthermore self.selectedRow looks like an NSDictionary. Try removeObjectForKey: instead.
Should be,
for (int i = [entry count] -1; i > 0; i--]){ }
And try,
for (int i = 0 ; i < [selectedRow count]; i++) {
if([[selectedRow objectAtIndex: i] count] < 2){
[selectedRow removeObjectAtIndex: i];
}
}
Related
This question already has answers here:
Removing object from NSMutableArray
(5 answers)
Closed 9 years ago.
I have an NSMutableArray of objects which are of AdDetail class that hold a few properties (for eg. adId, adTitle, adPrice... etc). I want to remove only those objects which have adID = 0. How can I do that ?
Perhaps something more elegant would suffice?
[array removeObjectsInArray:[array filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:#"adID == 0"]]];
Using predicate
NSArray *filtered=[array filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:#"(adId == 0)"]];
Using fastEnumeration:
NSMutableArray *newArray=[NSMutableArray new];
for(AdDetail adDetailObj in array){
if(![[adDetailObj adId] isEqualToString:#"0"]){ //if these are strings, if NSInteger then directly compare using ==
newArray[newArray.count]=adDetailObj;
}
}
Now newArray contains all objects other than id=0
Use following code :
int count = array.count;
for(i=0;i<count;i++){
ADetail *adetail = [array objectAtIndex:i];
if(adetail.adID = 0){
[array removeObjectAtIndex:i];
i--;
}
count = array.count;
}
NSMutableArray *newArray = [NSMutableArray arrayWithArray:yourArray];
for (int i = 0; i < yourArray.count; i++)
{
AdDetail *obj = (AdDetail *)[yourArray objectAtIndex:i];
if (obj.adID == 0)
[newArray removeObjectAtIndex:i];
}
yourArray = [newArray mutableCopy];
for(i=0; i < myArray.count; i++)
{
myClass = [myArray objectAtIndex:i];
if([myClass.adID isEqualtoString:"0"])// if it it int/NSInteger the write myClass.adID==0
{
[myArray removeObjectAtIndex:i];
i--;
}
}
predicate = #"adID == 0";
newArray = [theArray filterUsingPredicate:aPredicate]
I'm trying to shuffle an NSMutableArray so that its order will be mixed up every-time someone loads the view.
In my -(void)viewDidLoad I'm putting the following code (as suggested by other users):
NSMutableArray *shuffleTwo = [self.chosenTeamDict objectForKey:#"clubs"];
int random = arc4random() % [shuffleTwo count];
for (int i = 0; i < [shuffleTwo count]; i++) {
[shuffleTwo exchangeObjectAtIndex:random withObjectAtIndex:i];
}
NSLog(#"%#", shuffleTwo);
But when I do this and try and run the page, I get the following error:
2012-07-09 18:42:16.126 Kit-Quiz[6505:907] (null)
libc++abi.dylib: terminate called throwing an exception
Can anyone advice either a new way of shuffling this array, or advice me on how to avoid this error..!? I'm building for iOS 5 and I'm using Xcode45-DP1. Thanks in advance!
(EDIT)
I've also tried this method and I get the same error:
NSMutableArray *shuffledArray = [[NSMutableArray alloc] init];
NSMutableArray *standardArray = [self.chosenTeamDict objectForKey:#"clubs"];
for(int s = 0; s < [standardArray count]; s++){
int random = arc4random() % s;
[shuffledArray addObject:[standardArray objectAtIndex:random]];
}
NSLog(#"%#", shuffledArray);
NSMutableArray *standardArray = [self.chosenTeamDict objectForKey:#"clubs"];
int length = 10; // int length = [yourArray count];
NSMutableArray *indexes = [[NSMutableArray alloc] initWithCapacity:length];
for (int i=0; i<10; i++) [indexes addObject:[shuffledArray objectAtIndex:i]];
NSMutableArray *shuffle = [[NSMutableArray alloc] initWithCapacity:length];
while ([indexes count])
{
int index = rand()%[indexes count];
[shuffle addObject:[indexes objectAtIndex:index]];
[indexes removeObjectAtIndex:index];
}
for (int i=0; i<[shuffle count]; i++) NSLog(#"%#", [shuffle objectAtIndex:i]);
NSLog(#"%#", shuffle);
^^ ANSWER
Try Fisher-Yates shuffle. It goes like this:
int count = shuffledArray.count;
for(int i=count; i>0; i--) {
int j = arc4random_uniform(count);
[shuffledArray exchangeObjectAtIndex:j withObjectAtIndex:i];
}
make sure that your array is non-nil and all the entries are allocated objects :)
Source: Fisher-Yates Shuffle
First, you really should enable exception breakpoints. In XCode on the left-hand panel, click the breakpoint tab, click the "+" sign at the bottom-left -> exception breakpoint -> done.
I suspect your problem lies here:
int random = arc4random() % [shuffleTwo count];
If [shuffleTwo count] evaluates to zero (also if shuffleTwo is nil) it will throw a division by zero exception. Edit: Doesn't seem to be the case in Objective-C.
I am getting this data from JSON web services
[{"identity":"DEMO","assets":[{"identity":"34DL3611","systemId":"544507"},{"identity":"34GF0512","systemId":"5290211"},{"identity":"34HH1734","systemId":"111463609"},{"identity":"34HH1736","systemId":"111463622"},{"identity":"34YCJ15","systemId":"294151155"}],"systemId":4921244}]
I am using this method to get the values of assets for identity ("assets":[{"identity":"34DL3611","systemId":"544507"}):
vehicleList = [dict objectForKey: #"assets"];
self.listVehicles = [[NSMutableArray alloc] init];
for (NSUInteger index = 0; index < [vehicleList count]; index++) {
itemDict = [vehicleList objectAtIndex: index];
[self.listVehicles addObject:[itemDict objectForKey:#"identity"]];
}
how can I get the systemId values ... ?
I have tried this for systemId
vehicleListID = [dict objectForKey:#"systemId"];
self.listVehiclesID =[[NSMutableArray alloc]init];
for (NSUInteger index = 0; index < [vehicleListID count]; index++) {
assetsIdDict = [vehicleListID objectAtIndex: index];
[self.listVehiclesID addObject:[assetsIdDict objectForKey:#"systemId"]];
}
but getting error: [__NSCFNumber count]: unrecognized selector sent to instance 0x784c730
You're basically almost there. You just want this probably:
NSString *systemId = [itemDict objectForKey:#"systemId"];
With regard to this code you have:
vehicleListID = [dict objectForKey:#"systemId"];
self.listVehiclesID =[[NSMutableArray alloc]init];
for (NSUInteger index = 0; index < [vehicleListID count]; index++) {
assetsIdDict = [vehicleListID objectAtIndex: index];
[self.listVehiclesID addObject:[assetsIdDict objectForKey:#"systemId"]];
}
... well that is just totally wrong. That's returning the NSNumber which in your example JSON is 4921244 right at the end of the JSON string. You're then calling count on it, but it's not an array, so it crashes.
If you want to get all the values out of that JSON you can use this:
NSNumber *outerIdentity = [dict objectForKey:#"identity"];
NSNumber *outerSystemId = [dict objectForKey:#"systemId"];
NSArray *vehicleList = [dict objectForKey:#"assets"];
for (NSUInteger index = 0; index < [vehicleList count]; index++) {
NSDictionary *itemDict = [vehicleList objectAtIndex: index];
NSString *identity = [itemDict objectForKey:#"identity"];
NSString *systemId = [itemDict objectForKey:#"systemId"];
}
Then do whatever it is you want to do with all those objects.
The json response you are getting is an array. vehicleList should be the objectatIndex 0 of json response.
NSDictionary *vehicleList = [[arrayLoadedFromJson objectAtIndex:0] objectForKey: #"assets"];
vehicleList = [dict objectForKey: #"assets"];
self.listVehicles = [[NSMutableArray alloc] init];
for (NSUInteger index = 0; index < [vehicleList count]; index++) {
itemDict = [vehicleList objectAtIndex: index];
[self.listVehicles addObject:[itemDict objectForKey:#"identity"]];
[self.listVehicles addObject:[itemDict objectForKey:#"systemId"]];
}
This you have to insert:-in your code
[self.listVehicles addObject:[itemDict objectForKey:#"systemId"]];
For that to having in separate array, you need to initialize new NSMutableArray and add the objects.
Else, the better way is, declare a new class with 2 NSString members say, identity and systemId. Extract the values from JSON and assign to the class members. And add that object to the array.
I have an array which contains strings like frame_10#3x.png , frame_5#3x.png,frame_19#3x.png etc.
So I want to sort this array according to the number after the underscore i.e. the correct sequence will be frame_5#3x.png,frame_10#3x.png,frame_19#3x.png.
I tried to use the following method but no result:
NSInteger firstNumSort(id str1, id str2, void *context) {
int num1 = [str1 integerValue];
int num2 = [str2 integerValue];
if (num1 < num2)
return NSOrderedAscending;
else if (num1 > num2)
return NSOrderedDescending;
return NSOrderedSame;
}
Please suggest how to do this sorting for array.
NSArray *sry_img = [[NSArray alloc] initWithObjects:#"frame_18#3x.png",#"frame_17#3x.png",#"frame_1222#3x.png",#"frame_10#3x.png",#"frame_3#3x.png",#"frame_4#3x.png",#"frame_4#3x.png",#"frame_1#3x.png",#"frame_4#3x.png",#"frame_4#3x.png",nil];
NSArray *sortedStrings = [sry_img sortedArrayUsingSelector:#selector(localizedStandardCompare:)];
NSLog(#"%#",sortedStrings);
Enjy .......
But
localizedStandardCompare:, added in 10.6, should be used whenever file names or other strings are presented in lists and tables where Finder-like sorting is appropriate. The exact behavior of this method may be tweaked in future releases, and will be different under different localizations, so clients should not depend on the exact sorting order of the strings.
you want to do something like:
NSArray *components1 = [str1 componentsSeparatedByString:#"_"];
NSArray *components2 = [str2 componentsSeparatedByString:#"_"];
NSString *number1String = [components1 objectAtIndex:([components1 count] - 1])];
NSString *number2String = [components2 objectAtIndex:([components2 count] - 1])];
return [number1String compare:number2String];
I am not sure if my solution is the best possible approach but it can solve your problem for the time being :) .
1) First I have written a function to get the numbers before # character in your string and then I implemented simple SELECTION SORT algo to sort the array using this functions.
- (NSString*)getSubStringForString:(NSString*)value {
// First we will cut the frame_ string
NSMutableString *trimmedString = [NSMutableString stringWithString:[value substringWithRange:NSMakeRange(6, [value length]-6)]];
// New String to contain the numbers
NSMutableString *newString = [[NSMutableString alloc] init];
for (int i = 0; i < [trimmedString length] ; i++) {
NSString *singleChar = [trimmedString substringWithRange:NSMakeRange(i, 1)];
if (![singleChar isEqualToString:#"#"]) {
[newString appendString:singleChar];
} else {
break;
}
}
return newString;
}
This is the selection Implementation of the algo for sorting. The main logic is in the for loop. You can copy the code in viewDidLoad method to test.
NSMutableArray *array = [[NSMutableArray alloc] initWithObjects:#"frame_10#3x.png",#"frame_5#3x.png",
#"frame_3#3x.png", #"frame_19#3x.png",
nil];
NSLog(#"Values before Sort: %#", array);
int iPos;
int iMin;
for (iPos = 0; iPos < [array count]; iPos++)
{
iMin = iPos;
for (int i = iPos+1; i < [array count]; i++)
{
if ([[self getSubStringForString:[array objectAtIndex:i]] intValue] >
[[self getSubStringForString:[array objectAtIndex:iMin]] intValue]) {
iMin = i;
}
}
if ( iMin != iPos )
{
NSString *tempValue = [array objectAtIndex:iPos];
[array replaceObjectAtIndex:iPos withObject:[array objectAtIndex:iMin]];
[array replaceObjectAtIndex:iMin withObject:tempValue];
}
}
NSLog(#"Sorted Values: %#", array);
I hope that it can atleast keep you going. :)
You can try this-
NSString *str1 = [[[[str1 componentsSeparatedByString:#"frame_"] objectAtIndex:1] componentsSeparatedByString:#"#3x.png"] objectAtIndex:0];
int num1 = [str1 integerValue];
NSMutableArray*array = [[NSMutableArray alloc]init];
NSArray*Somearray = [NSArray arrayWithObjects:1st Object,2ndObject,3rd Object,4th object,5th Object,nil];
In the above array 1st Object,2ndObject,3rd Object,4th object,5th Object having val,content,conclusion in each index.
for(int i=0;i<[Somearray count];i++)
{
______________
Here the code is there to give each index ,that is having val,content,conclusion ..
After that val,content,conclusion in each index will be add to Dict..
____________
NSDictionary *Dict = [NSDictionary dictionaryWithObjectsAndKeys:val,#"val",content,#"content",conclusion,#"conclusion",nil];
//Each time adding dictionary into array;
[array addObject:Dict];
}
The above Dictionary is in for loop and the keyvalue pairs will be add 5 times(Somearray Count).Now array is having in
array = [{val="1.1 this is first one",content="This is the content of 0th index",conclusion="this is the conclusion of 0th index"},{val="1.2 this is first one",content="This is the content of 1st index",conclusion="this is the conclusion of 1st index"},____,____,______,{val="1.5 this is first one",content="This is the content of 4th index",conclusion="this is the conclusion of 4th index"},nil];
Now i am having NSString*string = #"1.5";
Now i need the index where val is having 1.5 in it.How to send the str in to array to find the the index.
Can anyone share the code please.
Thanks in advance.
Use method indexOfObject
int inx= [array indexOfObject:#"1.5"];
For Find index particular key value.
int inx;
for (int i=0; i<[array count]; i++) {
if ([[[array objectAtIndex:i] allKeys] containsObject:#"val"]) {
inx=i;
break;
}
}
The method you are looking for is -[NSArray indexOfObjectPassingTest:]. You would use it like this:
NSUInteger i = [array indexOfObjectPassingTest:^(id obj, NSUInteger idx, BOOL *stop) {
return [[id objectForKey:#"val"] rangeOfString:#"1.5"].location != NSNotFound;
}];
If you just want to check that val starts with "1.5" you would use hasPrefix: instead.
Try this -
NSArray *valArray = [array valueForKey:#"val"];
int index = [valArray indexOfObject:#"1.5"];
Appended answer given by Mandeep, to show you the magic of key value coding ;)
NSUInteger idx = UINT_MAX;
NSCharacterSet* spaceSet = [NSCharacterSet whitespaceCharacterSet];
for(int i=0,i_l=[Yourarray count];i<i_l;i++) {
NSString* s_prime = [[Yourarray objectAtIndex:i] valueForKey:#"val"];
if ([s_prime length] < 4) {
continue;
}
NSString *subString = [[s_prime substringToIndex:4] stringByTrimmingCharactersInSet:spaceSet];
// NSLog(#"index %#",s);
if ([subString isEqualToString:secretNumber]){
idx = i;
break;
}
}
if (idx != UINT_MAX) {
// NSLog(#"Found at index: %d",idx);
} else {
// NSLog(#"Not found");
}