uiSearchBar ClearButton强制显示键盘

这是一个古老的问题,我刚刚遇到了同样的问题,并通过以下方式解决了它:

当 searchBar:textDidChange: 调用uisearchbardelegate的方法是因为用户点击“清除”按钮,搜索栏还没有成为第一响应者,因此我们可以利用它来检测用户实际上打算何时清除搜索,而不是将焦点转移到搜索栏和/或执行其他操作。

为了跟踪这一点,我们需要声明 BOOL 我们的viewController中的ivar也是searchbar委托(我们称之为 shouldBeginEditing )并设置初始值为 YES (假设我们的viewcontroller类称为searchviewcontroller):

@interface SearchViewController : UIViewController <UISearchBarDelegate> {
    // all of our ivar declarations go here...
    BOOL shouldBeginEditing;
    ....
}

...
@end



@implementation SearchViewController
...
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
    if ((self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil])) {
        ...
        shouldBeginEditing = YES;
    }
}
...
@end

稍后,在uisearchbardelegate中,我们实现 搜索栏:textdidchange: 和 searchBarShouldBeginEditing: 方法:

- (void)searchBar:(UISearchBar *)bar textDidChange:(NSString *)searchText {
    NSLog(@"searchBar:textDidChange: isFirstResponder: %i", [self.searchBar isFirstResponder]);
    if(![searchBar isFirstResponder]) {
        // user tapped the 'clear' button
        shouldBeginEditing = NO;
        // do whatever I want to happen when the user clears the search...
    }
}


- (BOOL)searchBarShouldBeginEditing:(UISearchBar *)bar {
    // reset the shouldBeginEditing BOOL ivar to YES, but first take its value and use it to return it from the method call
    BOOL boolToReturn = shouldBeginEditing;
    shouldBeginEditing = YES;
    return boolToReturn;
}

基本上就是这样。

最好的

我发现当textdidchange从触摸调用到“清除按钮”时,resignfirstresponder不起作用。然而,使用 performSelection: withObject: afterDelay: 似乎是一个有效的解决方法:

- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
{
    if ([searchText length] == 0) {
        [self performSelector:@selector(hideKeyboardWithSearchBar:) withObject:searchBar afterDelay:0];
    }
}

- (void)hideKeyboardWithSearchBar:(UISearchBar *)searchBar
{   
    [searchBar resignFirstResponder];   
}

我找到了一个非常安全的方法来知道是否已按下清除按钮,并忽略用户刚刚删除uisearchbar最后一个字符的时间。这里是:

- (BOOL)searchBar:(UISearchBar *)searchBar shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
    _isRemovingTextWithBackspace = ([searchBar.text stringByReplacingCharactersInRange:range withString:text].length == 0);

    return YES;
}

- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
{
    if (searchText.length == 0 && !_isRemovingTextWithBackspace)
    {
        NSLog(@"Has clicked on clear !");
    }
}

很简单,很简单,不是吗:)唯一需要注意的是,如果用户在编辑uisearchbar的uitextfield时单击“清除”按钮,则会有两个ping,而如果用户在不编辑时单击,则只有一个ping。

编辑: 我不能测试它,但这里是根据rotem的swift版本:

var isRemovingTextWithBackspace = false

func searchBar(searchBar: UISearchBar, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool
{
    self.isRemovingTextWithBackspace = (NSString(string: searchBar.text!).stringByReplacingCharactersInRange(range, withString: text).characters.count == 0)
    return true
}

func searchBar(searchBar: UISearchBar, textDidChange searchText: String)
{
    if searchText.characters.count == 0 && !isRemovingTextWithBackspace
    { 
        NSLog("Has clicked on clear !")
    }
}

@Rotem的更新(swift2):

var isRemovingTextWithBackspace = false

func searchBar(searchBar: UISearchBar, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {
    self.isRemovingTextWithBackspace = (NSString(string: searchBar.text!).stringByReplacingCharactersInRange(range, withString: text).characters.count == 0)
    return true
}

func searchBar(searchBar: UISearchBar, textDidChange searchText: String) {
    if searchText.characters.count == 0 && !isRemovingTextWithBackspace {
        NSLog("Has clicked on clear!")
    }
}

我使用了@boliva的答案和@radiospiel的组合 answer 另一个问题是:

@interface SearchViewController : UIViewController <UISearchBarDelegate> {
    // all of our ivar declarations go here...
    BOOL shouldBeginEditing;
    ....
}

...
@end

@implementation SearchViewController
...
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
    if ((self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil])) {
        ...
        shouldBeginEditing = YES;
    }
}
...

- (void) searchBar:(UISearchBar *)theSearchBar textDidChange:(NSString *)searchText {
    // TODO - dynamically update the search results here, if we choose to do that.

    if (![searchBar isFirstResponder]) {
        // The user clicked the [X] button while the keyboard was hidden
        shouldBeginEditing = NO;
    }
    else if ([searchText length] == 0) {
        // The user clicked the [X] button or otherwise cleared the text.
        [theSearchBar performSelector: @selector(resignFirstResponder)
                        withObject: nil
                        afterDelay: 0.1];
    }
}

- (BOOL)searchBarShouldBeginEditing:(UISearchBar *)bar {
    // reset the shouldBeginEditing BOOL ivar to YES, but first take its value and use it to return it from the method call
    BOOL boolToReturn = shouldBeginEditing;
    shouldBeginEditing = YES;
    return boolToReturn;
}
@end

根据我的经验,最好的解决办法就是 UIButton (背景清晰,无文本)在系统清除按钮上方,然后连接 IBAction

使用自动布局非常简单

- (IBAction)searchCancelButtonPressed:(id)sender {

    [self.searchBar resignFirstResponder];
    self.searchBar.text = @"";

    // some of my stuff
    self.model.fastSearchText = nil;
    [self.model fetchData];
    [self reloadTableViewAnimated:NO];

}

按ui搜索栏中的“清除”按钮会自动打开键盘,即使您调用 searchBar.resignFirstResponder() 内 textDidChange uiSearchBardelegate方法。

要在按“x”清除uisearchbar时实际隐藏键盘,请使用以下代码。这样,即使 文本转换 在uisearchbar中键入内容时调用,仅当删除其中的所有文本、使用“删除”按钮或单击“x”时才隐藏键盘:

extension ViewController: UISearchBarDelegate {
    func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
        if searchBar.text!.count == 0 {
            DispatchQueue.main.async {
                searchBar.resignFirstResponder()
            }
        } else {
            // Code to make a request here.
        }
    }
}

在您的结束方法中,为什么不清除uisearchbar?因为你也必须在那里辞职,所以这是有道理的。

在搜索栏中,委托呼叫要求您接受从旧值更改为新值的更改-您可以检测到新值为零,旧值不为零,以及自键盘上次打开以来用户未键入任何内容的指示器-然后在这种情况下,放弃搜索栏的第一响应者。但不确定键盘是否会立即显示。

我有一个非常相似的情况,我自己也可以试试。

触摸清除按钮会导致 searchText 是空的。实现这一点的另一种方法是检查 - (void)searchBar:(UISearchBar *)bar textDidChange:(NSString *)searchText :

- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
{
    if([searchText length] == 0)
    {
        [self dismissSearch];
    }
    else
    {
        self.searchResultsTable.hidden = YES;
        [self handleSearchForString:searchText];
    }
}

- (void)dismissSearch
{
    [self.searchBar performSelector: @selector(resignFirstResponder)
                  withObject: nil
                  afterDelay: 0.1];

    self.searchResultsTable.hidden = YES;
}

对于那些使用 UISearchController 在里面 IOS 8 向上,您只需将 ui搜索控制器 . 为了完整性,您还可能希望隐藏 取消 按钮,正如我所做的,自从清除 UISearchBar 实际上是在搜索中取消。如果你想用的话,我已经在下面添加了代码。

这样做的好处是,您可以将它用于任何类和视图,而不需要 UIViewController . 我甚至将包括如何初始化 ui搜索控制器 在这个解决方案的底部。

FJ探查杆

只有当您像我一样希望隐藏“取消”按钮时,才需要重写这个类。标记 searchController.searchBar.showsCancelButton = NO 好像不适合 IOS 8 . 我还没测试过 IOS 9 .

fjSouthBar

空的,但为了完整起见放在这里。

@import UIKit;

@interface FJSearchBar : UISearchBar

@end

F.S.

#import "FJSearchBar.h"

@implementation FJSearchBar

- (void)setShowsCancelButton:(BOOL)showsCancelButton {
    // do nothing
}

- (void)setShowsCancelButton:(BOOL)showsCancelButton animated:(BOOL)animated {
    // do nothing
}

@end

FJ搜索控制器

这里是你想要真正改变的地方。我分裂了 UISearchBarDelegate 因为,imho,这些类别使类更干净,更容易维护。如果您希望将委托保持在主类接口/实现中,那么非常欢迎您这样做。

FJ搜索控制器.h

@import UIKit;

@interface FJSearchController : UISearchController

@end

@interface FJSearchController (UISearchBarDelegate) <UISearchBarDelegate>

@end

FJ搜索控制器.m

#import "FJSearchController.h"
#import "FJSearchBar.h"

@implementation FJSearchController {
@private
    FJSearchBar *_searchBar;
    BOOL _clearedOutside;
}

- (UISearchBar *)searchBar {
    if (_searchBar == nil) {
        // if you're not hiding the cancel button, simply uncomment the line below and delete the FJSearchBar alloc/init
        // _searchBar = [[UISearchBar alloc] init];
        _searchBar = [[FJSearchBar alloc] init];
        _searchBar.delegate = self;
    }
    return _searchBar;
}

@end

@implementation FJSearchController (UISearchBarDelegate)

- (BOOL)searchBarShouldBeginEditing:(UISearchBar *)searchBar {
    // if we cleared from outside then we should not allow any new editing
    BOOL shouldAllowEditing = !_clearedOutside;
    _clearedOutside = NO;
    return shouldAllowEditing;
}

- (void)searchBarSearchButtonClicked:(UISearchBar *)searchBar {
    // hide the keyboard since the user will no longer add any more input
    [searchBar resignFirstResponder];
}

- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText {
    if (![searchBar isFirstResponder]) {
        // the user cleared the search while not in typing mode, so we should deactivate searching
        self.active = NO;
        _clearedOutside = YES;
        return;
    }
    // update the search results
    [self.searchResultsUpdater updateSearchResultsForSearchController:self];
}

@end

需要注意的部分:

1. 我把搜索栏和 BOOL 作为私有变量而不是属性,因为
   • 它们比私人财产更轻。
   • 它们不需要被外界看到或修改。
2. 我们检查 searchBar 是第一个响应者。如果不是,那么我们实际上停用搜索控制器,因为文本是空的,我们不再搜索。如果你 真的? 想要确定,你也可以确保 searchText.length == 0 .
3. searchBar:textDidChange: 在之前调用 searchBarShouldBeginEditing: 这就是为什么我们按这个顺序处理它。
4. 每次文本更改时,我都会更新搜索结果,但您可能需要移动 [self.searchResultsUpdater updateSearchResultsForSearchController:self]; 到 searchBarSearchButtonClicked: 如果只希望在用户按 搜索 按钮。

@boliva答案的快速版本。

class MySearchContentController: UISearchBarDelegate {

    private var searchBarShouldBeginEditing = true

    func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
        searchBarShouldBeginEditing = searchBar.isFirstResponder
    }

    func searchBarShouldBeginEditing(_ searchBar: UISearchBar) -> Bool {
        defer {
            searchBarShouldBeginEditing = true
        }
        return searchBarShouldBeginEditing
    }
}

我已经碰到过好几次了。我真的很感激人们给出的答案。

最后,我真的很想看到苹果只允许我们(开发者)检测什么时候按下了清除按钮。

很明显,按下它会被检测到,因为搜索框中的任何文本都会被清除。

我猜他们现在的优先顺序不是很高…但我真的希望苹果公司的人能给uisearchbar一点爱!