This is my first question to Stack Overflow. I have been using this site for a while and have used it's resources to figure out answers to my programming questions but I'm afraid I can't find the answer I'm looking for this time.
I've created these five strings:
//List five items from the book and turn them into strings
//1 Josh the Trucker
NSString *stringJosh = #"Josh the Trucker";
//2 The Witch from the Remote Town
NSString *stringWitch = #"The Witch from the Remote Town";
//3 Accepting the curse rules "Willingly and Knowingly"
NSString *stringRules = #"Accepting the curse rules, --Willingly and Knowingly--";
//4 Josh's time left to live--Five Days Alive Permitted
NSString *stringFiveDays = #"Josh's time left to live--Five Days Alive Permitted";
//5 The Fire Demon Elelmental
NSString *stringDemon = #"The Fire Demon Elelmental";
Then, I've put them in an array:
//Create an array of five items from the book
NSArray *itemsArray = [[NSArray alloc] initWithObjects:
stringJosh,
stringWitch,
stringRules,
stringFiveDays,
stringDemon,
nil];
Then, I created this mutable string where I need to loop through the array and append the items to a UIlabel.
NSMutableString *itemsString = [[NSMutableString alloc] initWithString:
#"itemsArray"];
Here's the loop, which displays the items in the console log.
for (int i=0; i<5; i++)
{
NSLog(#"Book Item %d=%#", i, itemsArray[i]);
}
My question is, how do I append these items into the UIlabel?
These functions are in my appledelegate.
In my viewDidAppear function (flipsideViewController) I have:
label8.text =""----thats where the looped info needs to go.
How do I do this?
I feel I need to put them together and append where the NSLog should be...but how do I transfer that info to the textlabel?
I hope I explained myself.
We haven't done ANY append examples, I guess this is where I need to get answers from the "wild"
This is the wildest coding environment I know so I'm hoping I can find some direction here.
Thanks for taking a look!
Once you have all your strings that you want to concatenate in NSArray you can combine them with single call (with whatever separator you want):
NSString *combinedString = [itemsArray componentsJoinedByString:#" "];
If you need more complex logic you can use NSMutableString to create result you want while iterating array, i.e.:
NSMutableString *combinedString = [NSMutableString string];
[itemsArray enumerateObjectsUsingBlock:^(NSString *obj, NSUInteger idx, BOOL *stop) {
[combinedString appendFormat:#"Book Item %d=%# ", idx, obj];
}];
Note also that it is better to iterate through collections using fast enumeration or block enumeration rather than using plain index-based for loop.
NSMutableString *labelText = [NSMutableString string];
int i = 0;
for (NSString *item in itemsArray)
[labelText appendFormat:#"Book Item %d=%#\n", i++, item];
label8.text = labelText;
DO this
UILabel *mainlabel;
mainlabel.text = [origText stringByAppendingString:get];
Add your text to mainlabel.. orig text is mutable string or else in forloop just append array object at index text to label.put above line of code in forloop
Related
I'm doing an RSVP reading project app where it blinks words on the screen. You can set the word chunk size (how many words you want displayed at a time) to either 1, 2, or 3. I got it working for 1 word by having my paragraph in a string and doing:
[self.textInput componentsSeparatedByString:#" ";
This makes me an array of words that I can use to blink one word at a time. How would I be able to do this with displaying 2 words at a time? Is there a way I can use this function again to do it differently, or should I iterate over this word array and make a new one with 2 word strings?
Any help or advice would be greatly appreciated as to what the best practice would to get this done. Thanks.
just like keith said create an array
NSArray *allwordsArray = [self.textInput componentsSeparatedByString:#" "];
Now you got all the info you need. Meaning you got the array with every word in it. Now its just a matter of putting it together. (I haven't tested this code)
NSMutableArray *twoWordArray = [[NSMutableArray alloc] init];
int counter=0;
for (int i=0; i<[allwordsArray count]; i++)
{
if (counter >= [allwordsArray count]) break;
NSString *str1 = [NSString stringwithformat#"%#", [allwordsArray objectAtIndex:counter]];
counter++;
if (counter >= [allwordsArray count]) break;
NSString *str2 = [NSString stringwithformat#"%#", [allwordsArray objectAtIndex:counter]];
NSString *combinedStr = [NSString stringwithformat#"%# %#", str1,str2];
[twoWordArray addObject: combinedStr];
counter++;
}
You have broken the string into components, which is on the right track. You could then make a smaller array that only includes components until you reach the chunk size. The final step would be to rejoin the string.
NSArray *components = [self.textInput componentsSeparatedByString:#" "];
NSRange chunkRange = NSMakeRange(0, chunkSize);
NSArray *lessComponents = [components subarrayWithRange:chunkRange];
NSString *newString = [lessComponents componentsJoinedByString:#" "];
- (void)retrieveData
{
NSURL * url = [NSURL URLWithString:#"***/connection.php"];
NSData * data = [NSData dataWithContentsOfURL:url];
_json = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil];
_questionsArray = [[NSMutableArray alloc]init];
for (int i = 0; i < _json.count; i++)
{
NSString * qID = [[_json objectAtIndex:i] objectForKey:#"id"];
NSString * qTitle = [[_json objectAtIndex:i] objectForKey:#"question_title"];
NSString * qA = [[_json objectAtIndex:i] objectForKey:#"A"];
NSString * qB = [[_json objectAtIndex:i] objectForKey:#"B"];
NSString * qC = [[_json objectAtIndex:i] objectForKey:#"C"];
NSString * qD = [[_json objectAtIndex:i] objectForKey:#"D"];
NSString * qAnswer = [[_json objectAtIndex:i] objectForKey:#"question_answer"];
question * myQuestion = [[question alloc] initWithQuestionID:qID andQuestionName:qTitle andQuestionA:qA andQuestionB:qB andQuestionC:qC andQuestionD:qD andQuestionAnswer:qAnswer];
[_questionsArray addObject:myQuestion];
}
[_json enumerateObjectsUsingBlock:^(NSDictionary *questionDictionary, NSUInteger idx, BOOL *stop) {
//Here I'm treating the index like an NSNumber, if your code is expecting a string instead use
//#(idx).stringValue
[_questions setObject:questionDictionary forKey:#(idx)];
//or the modern equivalent
//questions[#(idx)] = questionDictionary;
//If you want to use your 'questions class' then create one and put it into the array instead of the dictionary pulled from the array.
}];
NSLog( #"%#", _questions );
}
Logs (null)
random gobledy gook so my post isn't mostly code
random gobledy gook so my post isn't mostly code
random gobledy gook so my post isn't mostly code
random gobledy gook so my post isn't mostly code
random gobledy gook so my post isn't mostly code
If I understand your question correctly it becomes something like this
self.questions = .... //I assume this is the array you reference 'question' objects that is created by your retrieve data method
//this used to be created by pulling an object out of your questions dictionary with the key i interpreted as a string.
//now that it's an array you should be able to just reference it by index, assuming they were inserted in order
//I'm also assuming that what comes out of the aray is a question object given the code you provided with the signature
//- (id) initWithQuestionID: (NSString *) qID andQuestionName: (NSString *) qName andQuestionA: (NSString *) qA andQuestionB: (NSString *) qB andQuestionC: (NSString *) qC andQuestionD: (NSString *) qD andQuestionAnswer: (NSString *) qAnswer
Question *nextQuestion = self.questions[i];
self.answer = nextQuestion.questionAnswer;
self.questionLabel.text = nextQuestion.questionLabel;
//and so on
I also suggest the following edit to replace your for loop. It uses a for in loop instead, this saves you from having to keep track of an index and looks cleaner. It also helps so you don't keep repeating the [_json objectAtIndex:i] chunk of code. I also use modern objective-c syntax to access the dictionary.
for (NSDictionary *questionDictionary in _json)
{
NSString * qID = questionDictionary[#"id"];
NSString * qTitle = questionDictionary[#"question_title"];
...
question * myQuestion = [[question alloc] initWithQuestionID:qID andQuestionName:qTitle andQuestionA:qA andQuestionB:qB andQuestionC:qC andQuestionD:qD andQuestionAnswer:qAnswer];
[_questionsArray addObject:myQuestion];
}
If you need the key along with the object in the dictionary then you can clean it up in a similar way with the enumerateObjectsUsingBlock
[_json enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
//your code here
}];
EDIT
It sounds like what your really wanting to do is to pull down your JSON but keep all your other code the way it was when you were using a dictionary that you got from your plist. So in this case you want your parsing function to return a dictionary instead of an array. If that's the case it's worth sidestepping into computer science for a second.
NSDictionarys are also known as a hash, map, symbol table, or associative array. Some languages (such as Lua) don't have an array collection like NSArray, they only have dictionaries. From a dictionary you can create many of the other collections your used to like arrays (and sets too). Heres how it works: Instead of an ordered collection of elements with an index, you place the items in a dictionary and use what would have been the index as the key, and the value becomes, well, the value. For example an array and it's equivalent associative array (aka dictionary):
NSArray *array = #[#"hello", #"world", #"!"];
NSDictionary *dictionary = #{#(1): #"hello",
#(2): #"world",
#(3): #"!"};
This is exactly what your doing when you load in the data from your plist because the first elements key is 0 followed by another dictionary, and I'm supposing that the next element in the list is 1 followed by another dictionary. Inside your parsing function it becomes
NSMutableDictionary *questions = [[NSMutableDictionary alloc] init];
[_json enumerateObjectsUsingBlock:^(NSDictionary *questionDictionary, NSUInteger idx, BOOL *stop) {
//Here I'm treating the index like an NSNumber, if your code is expecting a string instead use
//#(idx).stringValue
[questions setObject:questionDictionary forKey:#(idx)];
//or the modern equivalent
//questions[#(idx)] = questionDictionary;
//If you want to use your 'questions class' then create one and put it into the array instead of the dictionary pulled from the array.
}];
This of course assumes that your api is going to return the JSON questions in the order you want.
My problem is that when I use fast enumeration to load objects from my array, like so:
for(SetOfObjects *set in _myArray){
NSLog (#"%#"[set anObject];
}
It will print out my specified object without a problem, however when it comes time to assign these objects to an NSArray of labels. The last object returns as 0.
Like so:
for(SetOfObjects *set in _myArray){
for(UILabel *label in _arrayOfLabels){
int i = [set intObject];
NSString *string = [NSString stringWithFormat:#"%i",i];
label.text = string;
}
}
I think, I have gone wrong here. The code works, but the problem is that all labels are then set as 0.
Any tips welcome.
You are iterating the labels within each SetOfObjects instance, when in fact you want to iterate both arrays at the same time, which cannot be done using fast enumeration.
Instead revert to indexed-access of both arrays:
NSInteger count = [_myArray count];
NSAssert([_arrayOfLabels count] == count, #"Different array sizes!");
for (NSInteger index = 0; index < count; index++) {
SetOfObjects *set = _myArray[index];
UILabel *label = _arrayOfLabels[index];
int i = [set intObject];
NSString *string = [NSString stringWithFormat:#"%i",i];
label.text = string;
}
Note the assertion to check that both arrays are the same size.
EDIT: Oops, i was a bad variable name to choose for the index...
This question already has answers here:
Is there a simple way to split a NSString into an array of characters?
(4 answers)
Closed 9 years ago.
I am trying to get each letter of an NSString using this line of code:
NSArray *array = [string componentsSeparatedByString:#""];
//string is equal to Jake
NSLog(#"Array Count:%d",[array count]);
I am expecting to get each letter of the word "Jake" but instead I am getting the whole word. Why?
From Apple's Doc about this method
NSString *list = #"Norman, Stanley, Fletcher";
NSArray *listItems = [list componentsSeparatedByString:#", "];
produces an array { #"Norman", #"Stanley", #"Fletcher" }.
So empty separator will not separate each character of string, this
method doesn't work this way.
Here is an answer for your question
How to convert NSString to NSArray with characters one by one in Objective-C
The idea of separating a string by nothing doesn't logically make sense, it is like trying to divide by zero.
But to answer the question:
NSMutableArray *stringComponents = [NSMutableArray arrayWithCapacity:[string length]];
for (int i = 0; i < [string length]; i++) {
NSString *character = [NSString stringWithFormat:#"%c", [string characterAtIndex:i]];
[stringComponents addObject:character];
}`
Okay I am new to objective C and am trying hard to learn it on my own with out bother the stacked overflow community to much but it is really quite different then what I'm used to (C++).
But I have come across a issue that I for the life of me can't figure out and I'm sure it's going be something stupid. But I am pulling questions and answers from a website that then will display on my iOS application by using this code.
NSString * GetUrl = [NSString stringWithFormat:#"http://www.mywebpage.com/page.php"];
NSString * GetAllHtml = [NSString stringWithContentsOfURL:[NSURL URLWithString:GetUrl] encoding:1 error:nil];
NSString *PullWholeQuestion = [[GetAllHtml componentsSeparatedByString:#"<tr>"] objectAtIndex:1];
NSString *FinishWholeQuestion = [[PullWholeQuestion componentsSeparatedByString:#"</tr>"] objectAtIndex:0];
After I get all of the webpage information I strip down each question and want to make it where it will do a loop process to pull the questions so basically I need to count how many array options there are for the FinishedWholeQuestion variable
I found this snippet online that seemed to work with there example but I cant repeat it
NSArray *stringArray = [NSArray arrayWithObjects:#"1", #"2", nil];
NSLog(#"count = %d", [stringArray count]);
"componentsSeparatedByString" returns an NSArray object, not a single NSString.
An array object can contain zero, one or more NSString objects, depending on the input.
If you change "FinishWholeQuestion" into a NSArray object, you'll likely get a few components (separate by a string).
And now that I'm looking at your code a little more closely, I see you're making an assumption that your array is always valid (and has more than 2 entries, as evidenced by the "objectAtIndex: 1" bit).
You should also change the first character of all your Objective-C variables. Best practices in Objective-C are that the first character of variables should always be lower case.
Like this:
NSString * getUrl = [NSString stringWithFormat:#"http://www.mywebpage.com/page.php"];
NSString * getAllHtml = [NSString stringWithContentsOfURL:[NSURL URLWithString:getUrl] encoding: NSUTF8StringEncoding error:nil];
NSArray * allQuestions = [getAllHtml componentsSeparatedByString:#"<tr>"];
if([allQuestions count] > 1)
{
// assuming there is at least two entries in this array
NSString * pullWholeQuestion = [allQuestions objectAtIndex: 1];
if(pullWholeQuestion)
{
NSString *finishWholeQuestion = [[pullWholeQuestion componentsSeparatedByString:#"</tr>"] objectAtIndex:0];
}
}