how to add border outline stroke and fill stroke on CATextLayer text

Question

Here is code,

text1 =[[NSMutableAttributedString alloc]initWithAttributedString:t.string];
            NSDictionary* attributes = @{(NSString*)kCTStrokeWidthAttributeName: @(-slider.value),
                                         (NSString*)kCTStrokeColorAttributeName: (id)curruntColor ,
                                         (NSString*)kCTForegroundColorAttributeName:(id)(textView.textColor)};

            [text1 addAttributes:attributes range:NSMakeRange(0, text1.length)];
            text1=[self getScaledStringFrom:text1 withScale:1];
            t.string=text1;

slider value is the width of stroke, t.string means text layer string. thanks