关于iPhone:在触摸结束之前,如何在按钮的单击事件上启动活动指示器?

way to start activity indicator on click event of button before its touch ends?

我正在通过我的应用程序上传图像。我使用了以下代码

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-(IBAction)submitimage:(id)sender
{
        // [activity startAnimating]; i started activity here but it starts after completion of function
    NSString *name, *comments;
    comments = txtcomment.text;
    name = @"Anonymous";
    int r=random()%10000;
    NSLog(@"random number:%d",r );
    NSString *imageName=[NSString stringWithFormat:@"Content-Disposition: form-data; name="dashboard"; filename="%d.jpg"\
\
"
,r];

    NSData *imageData = UIImageJPEGRepresentation(imge, 90);
        //NSLog(@"imagedata=%@",imageData);
    NSString *urlString =[NSString stringWithFormat:@"http://www.xyzsite.com/webservices/&comment=%@&name=%@",comments,name];



        //NSLog(@"urlsubmit=%@",urlString);
    NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
    [request setURL:[NSURL URLWithString:urlString]];
    [request setHTTPMethod:@"POST"];
    NSString *boundary = [NSString stringWithString:@"---------------------------14737809831466499882746641449"];
    NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary];
    [request addValue:contentType forHTTPHeaderField: @"Content-Type"];

    /*  body of the post */
    NSMutableData *body = [NSMutableData data];
    [body appendData:[[NSString stringWithFormat:@"\
\
--%@\
\
"
,boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:[[NSString stringWithString:imageName] dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\
\
\
\
"
] dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:[NSData dataWithData:imageData]];
    [body appendData:[[NSString stringWithFormat:@"\
\
--%@--\
\
"
,boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    [request setHTTPBody:body];
    NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
    NSString *returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];
    NSLog(@"%@",returnString);
}

但是动画在功能结束后开始,所以还有其他方法可以启动活动指示器。在触摸事件结束之前。我在两个不同的上载图像应用程序中遇到相同的问题。所以如果有人知道,那么请让我知道
谢谢


对此可能有不止一种解决方案。但是,您可以将活动指示开始动画动作移至TouchDown事件,而将另一个留在" Touch up Inside"中。