1.placeHolder靠左
建立一个类别，名字自取，并在.h文件中创建一个方法
@interface UISearchBar (MySearchBarPlaceholder)
-(void)changeLeftPlaceholder:(NSString *)placeholder;
.m文件中实现方法
-(void)changeLeftPlaceholder:(NSString *)placeholder {
self.placeholder = placeholder;
SEL centerSelector = NSSelectorFromString([NSString stringWithFormat:@"%@%@", @"setCenter", @"Placeholder:"]);
if ([self respondsToSelector:centerSelector]) {
BOOL centeredPlaceholder = NO;
NSMethodSignature *signature = [[UISearchBar class] instanceMethodSignatureForSelector:centerSelector];
NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:signature];
[invocation setTarget:self];
[invocation setSelector:centerSelector];
[invocation setArgument:¢eredPlaceholder atIndex:2];
[invocation invoke];
}
}
在要使用的视图导入类别
#import "UISearchBar+MySearchBarPlaceholder.m"
在要使用的位置直接调用
[_searchBar changeLeftPlaceholder:@"企业名称"];
