@selector的函式如何傳引數/如何傳遞多個引數
阿新 • • 發佈:2019-01-08
不同的類會有不同的傳遞方式,引數名也不盡相同。如果是傳單個引數的就不用集合,如果是傳多個引數可以用類似nsarray,nsdictionary之類的集合傳遞。看下面例子:
例子1:
通過NSTimer看IPhone對@selector的函式如何傳引數,
NSMutableDictionary *dict = [[NSMutableDictionary alloc] init]; if(oldView != nil) { [dict setObject:oldView forKey:@"oldView"]; }if(newView != nil) { [dict setObject:newView forKey:@"newView"]; } [NSTimer scheduledTimerWithTimeInterval:0.0 target:self selector:@selector(onTimer:) userInfo:dict repeats:NO]; [dict release]; - (void)onTimer:(NSTimer *)timer { UIView *oldView = [[timer userInfo] objectForKey:@"oldView"]; UIView *newView = [[timer userInfo] objectForKey:@"newView"]; [UIView animateWithDuration:2.0 delay:0 options:UIViewAnimationOptionAllowUserInteraction animations:^{ oldView.alpha = 0.0; newView.alpha= 1.0; } }
從上可以看出,NSTimer在對@selector(onTimer:)傳遞引數時,將傳參的物件儲存在了NSTimer的userInfo的字典裡,在- (void)onTimer:(NSTimer *)timer中
通過取出該字典加以使用。
例子2:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
-(
void
)addNotifications:(NSArray*)data{
if
(data==nil||data.count!=2) {
return
;
}
//nsstring字串轉nsinteger
NSInteger notifyNum=[(NSString*)data[0] intValue];
NSInteger index=[data[1] intValue];
MyNBTabButton *button=_buttonData[index];
[button.light addNotifications:notifyNum];
}<br><br>
//呼叫
|
-(void)addNotificationAfterTime
{
[NSThread sleepForTimeInterval:20];//休眠多少秒之後
[self performSelectorOnMainThread:@selector(addNotifications:) withObject:[NSArray arrayWithObjects:@"1",@"2", nil] waitUntilDone:NO];
[NSThread sleepForTimeInterval:1.0];
}
這個其實也就是iphone對@selector物件傳參的通用的形式。
轉載請註明:http://www.cnblogs.com/langtianya/p/4199409.html