原文
目的是實現如下的效果:
UITextField的leftView是自定義的UIView,其中:
1、包含一個居中顯示的icon,并且上,左,下各有1px的間隙
2、左上和左下是圓角,右邊沒有圓角
居中展示icon
關鍵是leftView不是UIImageView,而是把UIImageView設置為subview
CGFloat height = frame.size.height;
UIView *leftView = [[UIView alloc] initWithFrame:CGRectMake(0, 1, height - 1, height - 2)];
UIImageView *icon = [[UIImageView alloc] initWithImage:[UIImage imageNamed:iconName]];
icon.frame = CGRectMake(height / 4, height / 4, height / 2, height / 2);
[leftView addSubview:icon];
上面的代碼,使icon在leftView居中顯示
制造1px間隙
top和bottom的間隙很容易做,只要令leftView的height比UITextField的height少2,然后y設置為1
左側的間隙比較麻煩,首先將width設置為比UITextField的width少1。但是直接設置x為1無效,需要override以下方法:
-(CGRect) leftViewRectForBounds:(CGRect)bounds {
CGRect iconRect = [super leftViewRectForBounds:bounds];
iconRect.origin.x += 1;
return iconRect;
}
制造部分圓角
制造所有的圓角比較簡單,只需要:
self.layer.cornerRadius = 5;
但是要制造部分圓角,就比較麻煩:
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:leftView.bounds byRoundingCorners:UIRectCornerTopLeft | UIRectCornerBottomLeft cornerRadii:CGSizeMake(5, 5)];
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
maskLayer.frame = leftView.bounds;
maskLayer.path = maskPath.CGPath;
leftView.layer.mask = maskLayer;
創建陰影
self.layer.shadowColor = [UIColor colorWithRed:132/255.0f green:214/255.0f blue:219/255.0f alpha:1.0f].CGColor;
self.layer.shadowOpacity = 0.5;
self.layer.shadowOffset = CGSizeMake(3, 3);
完整的代碼
@implementation LosTextField
-(id)initWithFrame:(CGRect)frame Icon:(NSString*)iconName
{
self = [super initWithFrame:frame];
if (self) {
CGFloat height = frame.size.height;
UIView *leftView = [[UIView alloc] initWithFrame:CGRectMake(0, 1, height - 1, height - 2)];
leftView.backgroundColor = [UIColor colorWithRed:132/255.0f green:214/255.0f blue:219/255.0f alpha:1.0f];
UIImageView *icon = [[UIImageView alloc] initWithImage:[UIImage imageNamed:iconName]];
icon.frame = CGRectMake(height / 4, height / 4, height / 2, height / 2);
[leftView addSubview:icon];
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:leftView.bounds byRoundingCorners:UIRectCornerTopLeft | UIRectCornerBottomLeft cornerRadii:CGSizeMake(5, 5)];
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
maskLayer.frame = leftView.bounds;
maskLayer.path = maskPath.CGPath;
leftView.layer.mask = maskLayer;
self.leftView = leftView;
self.leftViewMode = UITextFieldViewModeAlways;
}
return self;
}
-(CGRect) leftViewRectForBounds:(CGRect)bounds {
CGRect iconRect = [super leftViewRectForBounds:bounds];
iconRect.origin.x += 1;
return iconRect;
}
@end