弹出一个对话框

1.代码设置
{

//1.创建一个label
UILabel*lblMsg=[[UILabelalloc]init];
//1.1设置文字
lblMsg.text=@"正在下载中...";
//1.2设置背景色
lblMsg.backgroundColor=[UIColorblackColor];
//1.3设置文字颜色
lblMsg.textColor=[UIColorredColor];
//1.4设置frame
CGFloatmsgW=200;
CGFloatmsgH=40;
CGFloatmsgX=(self.view.frame.size.width-msgW)*0.5;
CGFloatmsgY=(self.view.frame.size.height-msgH)*0.5;
lblMsg.frame=CGRectMake(msgX, msgY, msgW, msgH);
//1.5修改label文字大小
//lblMsg.font=[UIFont systemFontOfSize:14];
//1.6设置文字居中显示
lblMsg.textAlignment=NSTextAlignmentCenter;
//1.7设置文字粗体
lblMsg.font=[UIFontboldSystemFontOfSize:14];
//1.8设置透明度
lblMsg.alpha=0.0;
//设置圆角
lblMsg.layer.cornerRadius=10;
lblMsg.layer.masksToBounds=YES;
//1.9通过动画方式显示label
[UIViewanimateWithDuration:1.5animations:^{
lblMsg.alpha=0.6;
}completion:^(BOOLfinished) {
if(finished) {
[UIViewanimateWithDuration:1.0delay:1.0options:UIViewAnimationOptionCurveLinearanimations:^{//匀速
lblMsg.alpha=0;
}completion:^(BOOLfinished) {
if(finished) {
[lblMsgremoveFromSuperview];
}
}];
}
}];
//2.把label加到self.view
//因为现在使用的是UITableViewController控制器,所以self.view就是UITableView,当把lblMsg加到self.view中,也就加到了UITableView中,所以滚动的时候也会随着滚动
//[self.view addSubview:lblMsg];
[[[UIApplicationsharedApplication]keyWindow]addSubview:lblMsg];
}
2.三方框架

【弹出一个对话框】导入MBProgressHUD

    推荐阅读