Storing UIColors in NSDictionary and retrieving them? - objective-c

Question

I need to return a specific UIColor for a given index.
I am trying to basically store the UIColors as NSArrays
TypeColors = [[NSDictionary alloc] initWithObjectsAndKeys:
#"1", [NSArray arrayWithObjects:[NSNumber numberWithFloat:0.5],[NSNumber numberWithFloat:0.5],[NSNumber
numberWithFloat:0.5],[NSNumber numberWithFloat:1.0], nil],
#"5", [NSArray arrayWithObjects:[NSNumber numberWithFloat:1.0],[NSNumber
numberWithFloat:0.5],[NSNumber numberWithFloat:0.1],[NSNumber
numberWithFloat:1.0], nil]
, nil]; //nil to signify end of objects and keys.
And here I want to retrieve the UIColor back from that dictionary:
a = 5;
NSArray* colorArray = [TypeColors objectForKey:a];
UIColor* color = [UIColor colorWithRed:[colorArray objectAtIndex:0]
green:[colorArray objectAtIndex:1] blue:[colorArray objectAtIndex:2]
alpha:[colorArray objectAtIndex:3]];
It always returns me a zero, anyone knows why?
Thanks!

Answer 1

Change it to
UIColor* color = [UIColor colorWithRed:[[colorArray objectAtIndex:0] floatValue]
green:[[colorArray objectAtIndex:1] floatValue] blue:[[colorArray objectAtIndex:2] floatValue]
alpha:[[colorArray objectAtIndex:3] floatValue]];
The parameter to be sent there is cgfloat and not NSNumber

Answer 2

Two things:
1) The order of things in initWithObjectsAndKeys are objects and then their keys. Yes, it is intuitively backwards.
2) The key is not an integer 5 but an NSString #"5".

Answer 3

You need to convert your UIcolor to Nsstring first before save it in dictionary as follow :
-(NSString *)convertColorToString :(UIColor *)colorname
{
if(colorname==[UIColor whiteColor] )
{
colorname= [UIColor colorWithRed:1 green:1 blue:1 alpha:1];
}
else if(colorname==[UIColor blackColor])
{
colorname= [UIColor colorWithRed:0 green:0 blue:0 alpha:1];
}
else
{
colorname=colorname;
}
CGColorRef colorRef = colorname.CGColor;
NSString *colorString;
colorString=[CIColor colorWithCGColor:colorRef].stringRepresentation;
return colorString;
}
and when you want to fetch the value from dictionary than you need to convert string to color as follow
-(UIColor *)convertStringToColor :(NSDictionary *)dicname :(NSString *)keyname
{
CIColor *coreColor = [CIColor colorWithString:[dicname valueForKey:keyname]];
UIColor *color = [UIColor colorWithRed:coreColor.red green:coreColor.green blue:coreColor.blue alpha:coreColor.alpha];
//NSLog(#"color name :%#",color);
return color;
}
exa :
here dicSaveAllUIupdate is my dictionary and i saved my view background color in it.
[dicSaveAllUIupdate setObject:[self convertColorToString: self.view.backgroundColor] forKey:#"MAINVW_BGCOLOR"];
and i will retrive it as follow
self.view.backgroundColor=[self convertStringToColor:retrievedDictionary:#"MAINVW_BGCOLOR"];
Hope this help to you ...