ios - UITableViewHeaderFooterView can't change background color to clearColor -

this tableheaderview class, extends uitableviewheaderfooterview. class not have nib file , done programmatically.

i want background color transparent, cannot make work. i've tried setting [self.backgroundview setbackgroundcolor:[uicolor clearcolor]], [self setbackgroundview:nil], [self.contentview setbackgroundcolor:[uicolor clearcolor]], final result black background.

i've spent hours on this, , have no idea how fix this. need working?

#import "tableheaderview.h"  @interface tableheaderview ()  @property (strong, nonatomic) uiview *background; @property (strong, nonatomic) uilabel *text;  @end  @implementation tableheaderview  - (instancetype)initwithreuseidentifier:(nsstring *)reuseidentifier {   self = [super initwithreuseidentifier:reuseidentifier];    if (self.contentview) {     self.background = [uiview new];     [self.background setbackgroundcolor:[uicolor colorwithwhite:0.0f alpha:0.5f]];     [self.background settranslatesautoresizingmaskintoconstraints:no];      self.text = [uilabel new];     [self.text settranslatesautoresizingmaskintoconstraints:no];     [self.text settext:@"label"];     [self.text setfont:[uifont fontwithname:@"helveticaneue" size:15.0f]];     [self.text settextcolor:[uicolor whitecolor]];     [self.text setbackgroundcolor:[uicolor redcolor]];      [self.background addsubview:self.text];     [self.contentview addsubview:self.background];      [self.contentview settranslatesautoresizingmaskintoconstraints:no];      [self.background addconstraints:[nslayoutconstraint constraintswithvisualformat:@"h:|-10-[l]-10-|"                                                                             options:0                                                                             metrics:nil                                                                               views:@{@"l": self.text}]];      [self.background addconstraints:[nslayoutconstraint constraintswithvisualformat:@"v:|[l]|"                                                                             options:0                                                                             metrics:nil                                                                               views:@{@"l": self.text}]];      [self.contentview addconstraints:[nslayoutconstraint constraintswithvisualformat:@"h:|-10-[v]-10-|"                                                                              options:0                                                                              metrics:nil                                                                                views:@{@"v": self.background}]];      [self.contentview addconstraints:[nslayoutconstraint constraintswithvisualformat:@"v:|-10-[v]|"                                                                              options:0                                                                              metrics:nil                                                                                views:@{@"v": self.background}]];      [self addconstraints:[nslayoutconstraint constraintswithvisualformat:@"h:|[contentview]|"                                                                  options:0                                                                  metrics:nil                                                                    views:@{@"contentview" : self.contentview}]];      [self addconstraints:[nslayoutconstraint constraintswithvisualformat:@"v:|[contentview]|"                                                                  options:0                                                                  metrics:nil                                                                    views:@{@"contentview" : self.contentview}]];      [self setbackgroundview:[uiview new]];                          // can't change background color     [self.backgroundview setbackgroundcolor:[uicolor whitecolor]];  // transparent. gets black instead.   }    return self; }  @end 

update

i tried using nib file , using initializer:

- (instancetype)initwithreuseidentifier:(nsstring *)reuseidentifier {   self = [super initwithreuseidentifier:reuseidentifier];                                                                           if (self) {     [self.contentview addsubview:[[[nsbundle mainbundle] loadnibnamed:@"tableheaderview" owner:self options:nil] firstobject]];   }   return self; } 

the nib file sets views old code. still doesn't work, can't transparent background.

update 2

the problem overriding drawrect:, , doing caused black background. moving code inside method solved problem.