取消UICollectionView的隐式动画
//方法一
[UIView performWithoutAnimation:^{
[collectionView reloadItemsAtIndexPaths:@[[NSIndexPath indexPathForItem:index inSection:0]]];
}];
//方法二
[UIView animateWithDuration:0 animations:^{
[collectionView performBatchUpdates:^{
[collectionView reloadItemsAtIndexPaths:@[[NSIndexPath indexPathForItem:index inSection:0]]];
} completion:nil];
}];
//方法三
[UIView setAnimationsEnabled:NO];
[self.trackPanel performBatchUpdates:^{
[collectionView reloadItemsAtIndexPaths:@[[NSIndexPath indexPathForItem:index inSection:0]]];
} completion:^(BOOL finished) {
[UIView setAnimationsEnabled:YES];
}];
判断邮箱格式是否正确的代码
-(BOOL)isValidateEmail:(NSString *)email
{
NSString *emailRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+.[A-Za-z]{2,4}";
NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES%@",emailRegex];
return [emailTest evaluateWithObject:email];
}
iOS中UITextField的字数限制
//在viewDidLoad中注册<UITextFieldTextDidChangeNotification>通知
[[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(textFiledEditChanged:)
name:@"UITextFieldTextDidChangeNotification" object:myTextField];
//实现监听方法
#pragma mark - Notification Method
-(void)textFieldEditChanged:(NSNotification *)obj
{
UITextField *textField = (UITextField *)obj.object;
NSString *toBeString = textField.text;
//获取高亮部分
UITextRange *selectedRange = [textField markedTextRange];
UITextPosition *position = [textField positionFromPosition:selectedRange.start offset:0];
// 没有高亮选择的字,则对已输入的文字进行字数统计和限制
if (!position)
{
if (toBeString.length > MAX_STARWORDS_LENGTH)
{
NSRange rangeIndex = [toBeString rangeOfComposedCharacterSequenceAtIndex:MAX_STARWORDS_LENGTH];
if (rangeIndex.length == 1)
{
textField.text = [toBeString substringToIndex:MAX_STARWORDS_LENGTH];
}
else
{
NSRange rangeRange = [toBeString rangeOfComposedCharacterSequencesForRange:NSMakeRange(0, MAX_STARWORDS_LENGTH)];
textField.text = [toBeString substringWithRange:rangeRange];
}
}
}
}
小伙伴们,今天就分享到这里,下期更精彩!
注:相关教程知识阅读请移步到IOS开发频道。










