警告框扩展应用：给UIAlertView添加UITextField模拟登录框
2011-12-22 13:54 张智清 阅读(2811) 评论(0) 编辑 收藏 举报首先要自定义一个UIAlertView扩展类，如MAlertView：
View Code
// MAlertView.h
//
#import <Foundation/Foundation.h>
@interface MAlertView:UIAlertView {
UITextField *passwdField;
NSInteger textFieldCount;
}
- (void)addTextField:(UITextField *)aTextField placeHolder:(NSString *)placeHolder;
@end
// MAlertView.m
//
#import "MAlertView.h"
#define kMAlertViewTextFieldHeight 30.0;
#define kMAlertViewMargin 10.0
@implementation MAlertView
- (void)initialize {
}
- (id)initWithTitle:(NSString *)title message:(NSString *)message delegate:(id)delegate cancelButtonTitle:(NSString *)cancelButtonTitle otherButtonTitles:(NSString *)otherButtonTitles,... {
if((self == [super initWithTitle:title message:message delegate:delegate cancelButtonTitle:cancelButtonTitle otherButtonTitles:otherButttonTitles,nil])) {
}
return self;
}
- (void)layoutSubviews {
CGRect rect = self.bounds;
rect.size.height += textFieldCount*(kMAlertViewTextFieldHeight + kMAlertViewMargin);
self.bounds = rect;
float maxLabelY = 0.f;
int textFieldIndex = 0;
for (UIView *view in self.subviews) {
if ([view isKindOfClass:[UIImageView class]]) {
}
else if ([view isKindOfClass:[UILabel class]]) {
rect = view.frame;
maxLabelY = rect.origin.y + rect.size.height;
}
else if ([view isKindOfClass:[UITextField class]]) {
rect = view.frame;
rect.size.width = self.bounds.size.width - 2*kMAlertViewMargin;
rect.size.height = kMAlertViewTextFieldHeight;
rect.origin.x = kMAlertViewMargin;
rect.origin.y = maxLabelY + kMAlertViewMargin*(textFieldIndex+1) + kMAlertViewTextFieldHeight*textFieldIndex;
view.frame = rect;
textFieldIndex++;
}
else { //UIThreePartButton
rect = view.frame;
rect.origin.y = self.bounds.size.height - 65.0;
view.frame = rect;
}
}
}
- (void)addTextField:(UITextField *)aTextField placeHolder:(NSString *)placeHolder{
if (aTextField != nil) {
textFieldCount++;
aTextField.frame = CGRectZero;
aTextField.borderStyle = UITextBorderStyleRoundedRect;
aTextField.placeholder = placeHolder;
[self addSubview:aTextField];
// [self setNeedsLayout];
}
}
@end
如何使用此扩展类：
MAlertView *alert = [[MAlertView alloc] initWithTitle:@"Title" message:nil delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"OK",nil];
[alert addTextField:accountField placeHolder:@"Account"];
[alert addTextField:passwdField placeHolder:@"Password"];
[alert show];
[alert release];
效果如图。
进行了简单的封装，只需要用addTextField:placeHolder:方法将textField加进去就好了，其他使用方法和UIAlertView完全一样。
再作些补充说明：因为UIAlertView只有在点击了按钮才能进行交互，所有的text值都是在点击之后获取对应的textField的值。
有些朋友说空值的情况，这个可以在点击之后判断如果是空值就再次弹出alertView就可以了。
以上是通过自定义UIAlertView扩展类来实现UIAlertView模拟登录框的。现在最新的iOS5.0的UIAlertView类控件本身已经可以通过设置属性alertViewStyle来实现了。这一属性可选类型如下：
typedef enum {
UIAlertViewStyleDefault = 0,
UIAlertViewStyleSecureTextInput,
UIAlertViewStylePlainTextInput,
UIAlertViewStyleLoginAndPasswordInput
}UIAlertViewStyle
