display images randomly in 3 UIButton using single array content - ios

Question

I have created three UIButton and i have 11 images in an array. I want to display that images randomly in each and every buttons.
Edited
button2Image, button3Image, button4Image is NSString,
button2Image = [topButtonArray objectAtIndex:l1Counter];
NSArray *reversed = [[testArray reverseObjectEnumerator] allObjects];
button3Image = [topButtonArray objectAtIndex:nextCounter+1];
int random = arc4random_uniform([topButtonArray count]);
button4Image = [topButtonArray objectAtIndex:random];
Note: I don’t want to display same image in each button.

Answer 1

NSArray *urImageArray;//11 images
NSMutableArray *threeImages = [[NSMutableArray alloc]init];
while ([threeImages count]<3) {
id image=[urImageArray objectAtIndex:[self getRandomNumberBetween:0 maxNumber:11-1]];
// Three images must be different
if (![threeImages containsObject:image]) {
[threeImages addObject:image];
}
}
firstButtonImage = [threeImages objectAtIndex:0];
twoButtonImage = [threeImages objectAtIndex:1];
thirdButtonImage = [threeImages objectAtIndex:2];
- (NSInteger)getRandomNumberBetween:(NSInteger)min maxNumber:(NSInteger)max
{
return min + arc4random() % (max - min + 1);
}

Answer 2

If the question is how to pick random elements from array, here is a nice article with examples: http://nshipster.com/random/.
For example:
NSMutableArray *resultArray = [[NSMutableArray alloc] init];
//i is number of required random elements
int i = 3;
while (i-->0)
{
if ([array count] > 0) {
int idx = arc4random_uniform([array count]);
[resultArray addObject:array[idx]];
//array is a mutable array whether the original one or it's deep copy
[array removeObjectAtIndex:idx];
}
}

Answer 3

For that you have to non-repeating random number. Then use that number to get the image from image array
arr123=[[NSMutableArray alloc]init];
int random = arc4random_uniform(11);
[arr123 addObject:[NSString stringWithFormat:#"%d",random]];
[self do1];
NSLog(#"%#",arr123);
int iMatch=0;
-(void)do1
{
int random = arc4random_uniform(11);
if([arr123 count]==2)
return;
for(int i=0;i<1;i++)
{
for(int j=0;j<[arr123 count];j++)
{
if(random==[[arr123 objectAtIndex:j] intValue])
{
iMatch=1;
break;
}
}
if(iMatch==1)
{
iMatch=0;
[self do1];
}
else
{
iMatch=0;
[arr123 addObject:[NSString stringWithFormat:#"%d",random]];
[self do1];
}
}
}
Then use the arr123 array to get the random images from image array using the random indexes

Answer 4

you should create an NSSet with the objects you get from the array. The NSSet has only distinct objects so you will add random objects from the array to the NSSet until the NSSet counts 3 objects. Look at apple NSSet documentation:
https://developer.apple.com/library/mac/documentation/cocoa/Reference/Foundation/Classes/NSSet_Class/Reference/Reference.html