我这用的都是很简单的用法啊

searchField = [[UIMapSearchField alloc] initWithFrame:CGRectMake(5.0f, ([UINavigationBar defaultSize].height - [UISearchField defaultHeight]) / 2., frame.size.width - 10., [UISearchField defaultHeight])];
[searchField setDisplayEnabled:YES];
[searchField setFont:font];
[searchField setClearButtonStyle:2];
[searchField setPaddingLeft:8.0f];
[searchField setPaddingTop:6.0f];
[[searchField textTraits] setReturnKeyType:6];
[[searchField textTraits] setEditingDelegate:self];