Flex：验证失败时强制显示控件的错误提示（错误工具提示）

Question

当验证器（即 StringValidator、NumberValidator 等）由于验证失败而调度无效事件时，源控件（即 TextInput）的 errorString 属性将设置为非空字符串，该字符串会在控件周围创建红色边框并显示仅当鼠标悬停在控件上时才出现工具提示（错误提示）。

问题：是否可以强制立即显示工具提示（错误提示），而不是等待用户将鼠标悬停在控件上？如果是这样，怎么办？

Answer 1

zdmytriv 的答案中链接的 Aral Balkan 的文章值得一读，并提倡为用户提供更好的整体验证交互。

如果您只是想“强制”弹出错误提示，我会这样做：

    public function showErrorImmediately(target:UIComponent):void
    {
        // we have to callLater this to avoid other fields that send events
        // that reset the timers and prevent the errorTip ever showing up.
        target.callLater(showDeferred, [target]);
    }

    private function showDeferred(target:UIComponent):void
    {
        var oldShowDelay:Number = ToolTipManager.showDelay;
        ToolTipManager.showDelay = 0;
        if (target.visible)
        {
            // try popping the resulting error flag via the hack 
            // courtesy Adobe bug tracking system
            target.dispatchEvent(new MouseEvent(MouseEvent.MOUSE_OUT));
            target.dispatchEvent(new MouseEvent(MouseEvent.MOUSE_OVER));
        }
        ToolTipManager.showDelay = oldShowDelay;
    }

    public function clearErrorImmediately(target:UIComponent):void
    {
        target.callLater(clearDeferred, [target]);
    }

    private function clearDeferred(target:UIComponent):void
    {
        var oldDelay:Number = ToolTipManager.hideDelay;
        ToolTipManager.hideDelay = 0;
        if (target.visible)
        {
            // clear the errorTip
            try
            {
                target.dispatchEvent(new MouseEvent(MouseEvent.MOUSE_OVER));
                target.dispatchEvent(new MouseEvent(MouseEvent.MOUSE_OUT));
            }
            catch (e:Error)
            {
                // sometimes things aren't initialized fully when we try that trick
            }
        }
        ToolTipManager.hideDelay = oldDelay;
    }

Answer 2

检查此Flex 中更好的表单验证