在进度条的开始和结束时大声朗读(md-progress-linear)

Question

在进度条的开始和结束时大声朗读(md-progress-linear)

Cod*_*man 9 screen-readers wai-aria angularjs progress-bar nvda

当出现带有进度条的对话框时,我需要使用NVDA屏幕阅读器来阅读一些消息.

在进度条的持续时间为0%时,我需要宣布: "您收到了定时消息"

进度条的持续时间为100%: "消息已过期"

使用的进度条是md-progress-linear.

html代码如下所示:

<md-dialog>
    <md-progress-linear tabindex="0" ng-if="displayProgressIndicator || timeoutValue > 0" md-mode="determinate" class="promptProgressBar" value="{{progressValue}}"></md-progress-linear>
    <md-content class="md-title dialogTitle">
        {{messageTitle}}
    </md-content>
    <md-content class="md-dialog-content">
        {{messageText}}
    </md-content>
    <div class="md-dialog-actions">
        <md-button ng-style="theme.SecondaryButton" ng-click="OnClose()" class="md-primary right">
            {{primaryActionText}}
        </md-button>
        <md-button ng-style="theme.SecondaryButton" ng-if="secondaryActionText.length > 0" ng-click="OnCancel()" class="md-primary right">
            {{secondaryActionText}}
        </md-button>
    </div>
</md-dialog>

Run Code Online (Sandbox Code Playgroud)

我看到一些滑块的工作示例,它使用aria-valuetext属性,NVDA正确读取这些文本.

我尝试在md-progress-linear元素中添加aria-valuetext属性,但不起作用.

当消息到达时,NVDA会发出蜂鸣声,但不会读取aria-valuetext.

有什么想法怎么做？