Insets就是css中的padding
我们给UITextField设置了leftView,目的是在文本输入框左側显示一个图标。可是在ios7里,这个图标会紧紧地挨着TextField的左边框,非常不美观,所以就希望设置一个Insets。可是直接设置ImageView的bounds不行,须要用以下这种方法:
@interface YLSTextField : UITextField-(id)initWithFrame:(CGRect)frame Icon:(UIImageView*)icon;@end
@implementation YLSTextField-(id)initWithFrame:(CGRect)frame Icon:(UIImageView*)icon{ self = [super initWithFrame:frame]; if (self) { self.leftView = icon; self.leftViewMode = UITextFieldViewModeAlways; } return self;}-(CGRect) leftViewRectForBounds:(CGRect)bounds { CGRect iconRect = [super leftViewRectForBounds:bounds]; iconRect.origin.x += 10;// 右偏10 return iconRect;}@end
UIImage *usernameImage = [UIImage imageNamed:@"user"];UIImageView *usernameIcon = [[UIImageView alloc] initWithImage:usernameImage];usernameIcon.frame = CGRectMake(0, 0, 20, 20); self.username = [[YLSTextField alloc] initWithFrame:CGRectMake(0, 0, 240, 30) Icon:usernameIcon];self.username.placeholder = @"用户名";self.username.borderStyle = UITextBorderStyleRoundedRect;self.username.clearButtonMode = UITextFieldViewModeWhileEditing;[self.username setKeyboardType:UIKeyboardTypeNumberPad];关键就是定义UITextField的子类,并覆盖其leftViewRectForBounds方法