UIWebView 屏蔽或者修改 alert警告框

如果是网页内容里面的alert,我们可以等网页加载完毕,也就是在webViewDidFinishLoad中执行下面的js代码,就可以屏蔽alert了

 

[myWebView stringByEvaluatingJavaScriptFromString:@"window.alert=null;"];



但上面的方法对于网页onLoad事件里面的alert就不起作用了



解决方法就是给UIWebView添加一个类别:



给工程添加JavaScriptAlert.h

@interface UIWebView (JavaScriptAlert) 
- (void)webView:(UIWebView *)sender runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame;
- (BOOL)webView:(UIWebView *)sender runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame;
@end


给工程添加JavaScriptAlert.m文件
@implementation UIWebView (JavaScriptAlert)
- (void)webView:(UIWebView *)sender runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame {
    /*
     UIAlertView* dialogue = [[UIAlertView alloc] initWithTitle:nil message:message delegate:nil cancelButtonTitle:@"好" otherButtonTitles:nil];
     [dialogue show];
     [dialogue autorelease];
     */
}
- (BOOL)webView:(UIWebView *)sender runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame{
   return NO;
}
@end

其实runJavaScriptAlertPanelWithMessage和runJavaScriptConfirmPanelWithMessage是UIWebDelegate的成员函数,详情可以查阅UIWebDelegate的帮助文档

 

 

 

 JavaScript中有三种形式的弹出框，alert，confirm，prompt；

修改alert内容的话：

捕捉 JavaScript alert()   JavaScript confirm()  JavaScript prompt()这三种形式的

给工程添加JavaScriptAlert.h

@interface UIWebView (JavaScriptAlert) 
- (void)webView:(UIWebView *)sender runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame;
- (BOOL)webView:(UIWebView *)sender runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame;
- (NSString *)webView:(UIWebView *)sender runJavaScriptTextInputPanelWithPrompt:(NSString *)str defaultText:(NSString *)mes initiatedByFrame:(WebFrame *)frame；

@end


给工程添加JavaScriptAlert.m文件
@implementation UIWebView (JavaScriptAlert)

static BOOL diagStat = NO;

1、

- (BOOL)webView:(UIWebView *)sender runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame
{
     NSLog(@"javascript alert : %@",message);
    UIAlertView *confirmDiag = [[UIAlertView alloc] initWithTitle:@"沃德餐饮提醒您" message:message delegate:self cancelButtonTitle:NSLocalizedString(@"Cancel", @"Cancel") otherButtonTitles:NSLocalizedString(@"OK", @"OK"), nil];
    [confirmDiag show];
    
    while (confirmDiag.hidden == NO && confirmDiag.superview != nil)
        
        [[NSRunLoop mainRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:0.01f]];
        
    [confirmDiag release];
    return diagStat;
}

 

 2、

- (void)webView:(UIWebView *)sender runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame {
    UIAlertView* customAlert = [[UIAlertView alloc] initWithTitle:@"沃德餐饮提醒您" message:message delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
    [customAlert show];
    [customAlert autorelease];  
}

 

3、
- (NSString *)webView:(UIWebView *)sender runJavaScriptTextInputPanelWithPrompt:(NSString *)str defaultText:(NSString *)mes initiatedByFrame:(WebFrame *)frame
{
    NSString *subTitle = [NSString stringWithFormat:@"%@\n\n",str];
    UIAlertView *promptDiag = [[UIAlertView alloc] initWithTitle:@"沃德餐饮提醒您" message:subTitle delegate:self cancelButtonTitle:NSLocalizedString(@"Cancel", @"Cancel") otherButtonTitles:NSLocalizedString(@"OK", @"OK"), nil];
    
    UITextField *nameField = [[UITextField alloc] initWithFrame:CGRectMake(10, 80, 265, 30)];
    //nameField.borderStyle =  UITextBorderStyleRoundedRect;
    nameField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
    [nameField becomeFirstResponder];
    nameField.backgroundColor = [UIColor whiteColor];
    [promptDiag addSubview:nameField];
    [nameField release];
    
    [promptDiag show];
    
    while (promptDiag.hidden == NO && promptDiag.superview != nil)
        
        [[NSRunLoop mainRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:0.01f]];
    
    [promptDiag release];
    if(diagStat)
    {
        return nameField.text;
    }
    return mes;
}
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    if (buttonIndex == 0)
    {
        diagStat = NO;
    } 
    else if (buttonIndex == 1) 
    {
        diagStat = YES;
    } 
}