tabbarcontrollerdelegate在任意一个子controller里面，全局点击都会跳进去

//tabbar delegate

- (BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController
NS_***AILABLE_IOS(3_0){

//当前展示的index tabBarController.selectedIndex

//将选中的页面viewcontroller

if (tabBarController.selectedIndex==viewController.view.tag) {

//

return NO;

}

else if (viewController.view.tag==3){

//≈

UIWebView*callWebview =[[UIWebView
alloc] init];



NSString *telUrl = [NSString
stringWithFormat:@"tel:4000559626"];



NSURL *telURL =[NSURL
URLWithString:telUrl];//
貌似tel://
或者 tel:
都行



[callWebview loadRequest:[NSURLRequest
requestWithURL:telURL]];



//每次点击都弹出电话拨打界面



[self.view
addSubview:callWebview];

return
NO;



}

else{

return YES;

}

}