在iOS 7 UISearchBar上,占位符文本居中,我想禁用它,并使其始终像以前一样粘在左边.
有一个私有的方法setCenterPlaceholder,在diff和调用这个与BOOL将做出旅程. https://gist.github.com/nscoding/7220368
标题文件
@interface NSCodingSearchBar : UISearchBar // Default by the system is YES. // https://github.com/nst/iOS-Runtime-Headers/blob/master/Frameworks/UIKit.framework/UISearchBar.h @property (nonatomic,assign,setter = setHasCentredplaceholder:) BOOL hasCentredplaceholder; @end
执行文件
#import "NSCodingSearchBar.h"
// ------------------------------------------------------------------------------------------
@implementation NSCodingSearchBar
// ------------------------------------------------------------------------------------------
#pragma mark - Initializers
// ------------------------------------------------------------------------------------------
- (instancetype)initWithFrame:(CGRect)frame
{
if ((self = [super initWithFrame:frame]))
{
self.hasCentredplaceholder = YES;
}
return self;
}
// ------------------------------------------------------------------------------------------
#pragma mark - Methods
// ------------------------------------------------------------------------------------------
- (void)setHasCentredplaceholder:(BOOL)hasCentredplaceholder
{
_hasCentredplaceholder = hasCentredplaceholder;
SEL centerSelector = NSSelectorFromString([Nsstring stringWithFormat:@"%@%@",@"setCenter",@"Placeholder:"]);
if ([self respondsToSelector:centerSelector])
{
NSMethodSignature *signature = [[UISearchBar class] instanceMethodSignatureForSelector:centerSelector];
NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:signature];
[invocation setTarget:self];
[invocation setSelector:centerSelector];
[invocation setArgument:&_hasCentredplaceholder atIndex:2];
[invocation invoke];
}
}
@end
我想知道是否有其他的,不是“哈奇的方式”做同样的事情.
解决方法
要在iOS7中保留占位符的左对齐方式,您可以在占位符字符串的末尾添加空格.例如：
_searchBar.placeholder = @"Search ";
请注意,应该为每个搜索栏和每种语言单独完成.
可以尝试在任何语言的文本之后自动计算所需的空格,但是似乎不可能读取searchBar的textField框架的大小
<UISearchBarTextField: 0x1349c160; frame = (0 0; 0 0);