textfield字数限制问题
UITextField *textField = [[UITextField alloc] initWithFrame:CGRectMake(originX, originY, width, height)];
textField.returnKeyType = UIReturnKeyDone; //return按钮为完成
textField.placeholder = @"限16个中文字";
//设置textfield的placeholder的字体大小和颜色
[textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];
[textField setValue:[UIFont boldSystemFontOfSize:12] forKeyPath:@"_placeholderLabel.font"];
//设置输入的文字的大小和颜色
[textField setFont:[UIFont systemFontOfSize:12]];
[textField setTextColor:[UIColor colorWithHexString:@"333333"]];
textField.textAlignment = NSTextAlignmentRight;
textField.delegate = self;
//监听textfield输入文字的个数
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textFieldDidChange:)
name:@"UITextFieldTextDidChangeNotification" object:self.clubNameTextField];
[self.view addSubview:textField];
#pragma mark textfield delegate
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
if ([string isEqualToString:@" "]) {
return NO; //不允许输入空格
}
return YES;
}
- (BOOL)textFieldShouldReturn:(UITextField *)textField {
[self.clubNameTextField endEditing:YES];
return YES;
}
- (void)textFieldDidChange:(NSNotification *)obj {
UITextField *textField = (UITextField *)obj.object;
NSString *toBeString = textField.text;
NSString *lang = [textField.textInputMode primaryLanguage];
if ([lang isEqualToString:@"zh-Hans"]) {// 简体中文输入
//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 || !selectedRange) {
if (toBeString.length > 16) {
NSRange rangeIndex = [toBeString rangeOfComposedCharacterSequenceAtIndex:16];
if (rangeIndex.length == 1) {
textField.text = [toBeString substringToIndex:16];
}else {
NSRange rangeRange = [toBeString rangeOfComposedCharacterSequencesForRange:NSMakeRange(0, 16)];
textField.text = [toBeString substringWithRange:rangeRange];
}
}
}
}else {// 中文输入法以外的直接对其统计限制即可，不考虑其他语种情况
if (toBeString.length > 16) {
NSRange rangeIndex = [toBeString rangeOfComposedCharacterSequenceAtIndex:16];
if (rangeIndex.length == 1) {
textField.text = [toBeString substringToIndex:16];
}else {
NSRange rangeRange = [toBeString rangeOfComposedCharacterSequencesForRange:NSMakeRange(0, 16)];
textField.text = [toBeString substringWithRange:rangeRange];
}
}
}
}
//如果需要配合键盘移动，不需要可忽略
-(void)viewWillAppear:(BOOL)animated{
[super viewWillAppear:animated];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
//监听textfield输入文字的个数
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textFieldDidChange:)
name:@"UITextFieldTextDidChangeNotification" object:self.clubNameTextField];
}
- (void)viewWillDisappear:(BOOL)animated {
[super viewWillDisappear:animated];
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
#pragma mark 键盘的通知
- (void)keyboardWillShow:(NSNotification *)noti {
NSValue *frameValue = [dict valueForKey:UIKeyboardFrameEndUserInfoKey];
CGRect frame = [frameValue CGRectValue];
//获取弹键盘前的偏移量
self.offsetY = self.tableView.contentOffset.y;
CGFloat height = frame.size.height;
self.tableView.contentInset = UIEdgeInsetsMake(0, 0, height, 0);
//将tableview滚动到textfield对应的行
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:7 inSection:0] atScrollPosition:UITableViewScrollPositionBottom animated:NO];//这里一定要设置为NO，动画可能会影响到scrollerView，导致增加数据源之后，tableView到处乱跳
}
- (void)keyboardWillHide:(NSNotification *)noti {
self.tableView.contentInset = UIEdgeInsetsZero;
}
