我正在使用一个文本输入的UIAlertView.
UIAlertView *alertView=[[UIAlertView alloc]initWithTitle:@"Save" message:@"Please Enter the Name of PDF" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"OK",nil]; [alertView setAlertViewStyle:UIAlertViewStylePlainTextInput]
当UITextField为空时,我想做什么我用代理功能禁用OK按钮
- (BOOL)alertViewShouldEnableFirstOtherButton:(UIAlertView *)alertView
{
return NO;
}
当用户开始在文本框中写入某些东西时,OK按钮应该被启用.
解决方法
请尝试这个
- (BOOL)alertViewShouldEnableFirstOtherButton:(UIAlertView *)alertView
{
/* Retrieve a text field at an index -
raises NSRangeException when textFieldIndex is out-of-bounds.
The field at index 0 will be the first text field
(the single field or the login field),The field at index 1 will be the password field. */
/*
1> Get the Text Field in alertview
2> Get the text of that Text Field
3> Verify that text length
4> return YES or NO Based on the length
*/
return [alertView textFieldAtIndex:0].text.length > 0;
}