咱們知道UITableView沒有像UIButton那樣能夠經過addTarget方法來監聽touch事件,所以在某些場合,特別是在UITableViewCell中包含UITextField的時候,咱們頗有可能想經過點擊UITableView的其餘地方來取消UITextField的焦點。也許有朋友會說,使用UITapGestureRecognizer手勢來取消焦點,這樣是能夠行得通,可是若是TextField中有clearButton或者其自定義的Button的時候,手勢就會吸取掉事件了,致使按鈕無效。atom
所以,我想到的作法就是重寫UITableView的touch相關的方法,而後經過委託的方式提供給外部對象使用。首先定義Delegate:code
@protocol TouchTableViewDelegate <NSObject> @optional - (void)tableView:(UITableView *)tableView touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event; - (void)tableView:(UITableView *)tableView touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event; - (void)tableView:(UITableView *)tableView touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event; - (void)tableView:(UITableView *)tableView touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event; @end
而後UITableView的子類加入一委託對象,並重寫全部touch相關方法,以下:orm
@interface TouchTableView : UITableView { @private id _touchDelegate; } @property (nonatomic,assign) id<TouchTableViewDelegate> touchDelegate; @end
@implementation TouchTableView @synthesize touchDelegate = _touchDelegate; - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { [super touchesBegan:touches withEvent:event]; if ([_touchDelegate conformsToProtocol:@protocol(TouchTableViewDelegate)] && [_touchDelegate respondsToSelector:@selector(tableView:touchesBegan:withEvent:)]) { [_touchDelegate tableView:self touchesBegan:touches withEvent:event]; } } - (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event { [super touchesCancelled:touches withEvent:event]; if ([_touchDelegate conformsToProtocol:@protocol(TouchTableViewDelegate)] && [_touchDelegate respondsToSelector:@selector(tableView:touchesCancelled:withEvent:)]) { [_touchDelegate tableView:self touchesCancelled:touches withEvent:event]; } } - (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { [super touchesEnded:touches withEvent:event]; if ([_touchDelegate conformsToProtocol:@protocol(TouchTableViewDelegate)] && [_touchDelegate respondsToSelector:@selector(tableView:touchesEnded:withEvent:)]) { [_touchDelegate tableView:self touchesEnded:touches withEvent:event]; } } - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { [super touchesMoved:touches withEvent:event]; if ([_touchDelegate conformsToProtocol:@protocol(TTWTableViewDelegate)] && [_touchDelegate respondsToSelector:@selector(tableView:touchesMoved:withEvent:)]) { [_touchDelegate tableView:self touchesMoved:touches withEvent:event]; } } @end
重寫touch方法時必須把父類實現方法寫上,不然UITableViewCell將沒法正常工做。全部的改寫工做如上所示,新的TableView類具備touch事件響應了,使用方法也很簡單在原有UITableView的基礎上賦予touchDelegate委託便可取到touch事件響應。以下:對象
- (void)loadView { [super loadView]; TouchTableView *tableView = [[TouchTableView alloc]initWithFrame:CGRectMake(0.0, 0.0, 320, 460) style:UITableViewStyleGrouped]; tableView.touchDelegate = self; //相關處理 [self.view addSubview:tableView]; [tableView release]; } - (void)tableView:(TTWTableView *)tableView touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { //touch結束後的處理 }