如何防止android对讲说话搜索栏进度

Question

我有一个扩展SeekBar的自定义控件，其中我覆盖了onLaunalizeAccessibilityNodeInfo，如下所示：

@Override
public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
    super.onInitializeAccessibilityNodeInfo(info);
    info.setClassName(TextView.class.getName());
}

然后我对这个控件设置内容描述为“我的控件”，但是当可访问性焦点来到这个控件时，talkback仍然说出“我的控件，%x percent”。我不希望它说进展，即“百分之x”。相反，我想覆盖对讲文本，而不是它宣布“x百分之……”它会显示我设置的自定义文本，例如“选定的x值”。怎么做？

Answer 1

对我来说，在API级别工作

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
    // prevent "zero percent" talkback; null or empty string does not work
    pbProgress.setStateDescription("\u2800");
}

Null将状态描述重置为其默认行为。空字符串或空格似乎被忽略了。

Answer 2

多亏了@nick-peppers回答 https://stackoverflow.com/a/58434362/2713403 我开始更好地了解AccessibilityDelegate的工作原理，所以我做了一个不同的解决方案，因为我想选择搜索栏。通过从OnInitializeAccessibilityEvent方法中删除超级调用，如果用户单击，则无法将选择保留在搜索栏上，因此我进行了此操作（在Android 11，10和9上进行了测试）

...
seekbar.setAccessibilityDelegate(new customSeekBarDelegate());
...

/**
 * Create a custom delegate to modify what Talkback is going to read out loud
 */
private class customSeekBarDelegate extends View.AccessibilityDelegate
{
    /**
     * If the selected view is the slider, populate the text to read by talkback.
     * On Android 10 and 9, the view got selected from the beginning without touch the slider,
     * so the TYPE_VIEW_SELECTED event is controlled.
     * The text should be overwritten to trigger what Talkback do need to read.
     *
     * @param host The view selected
     * @param event The event to initialise
     */
    @Override public void onInitializeAccessibilityEvent(View host, AccessibilityEvent event)
    {
        super.onInitializeAccessibilityEvent(host, event);
        if (event.getEventType() != AccessibilityEvent.TYPE_VIEW_SELECTED)
        {
            seekbarText.setText(seekbarText.getText());
        }
    }

    /**
     * Send all accessibility events except the focused accessibility event
     * because it reads the percentage, so it needs to be changed to no focused to read
     * the sliderText.
     *
     * @param host the view selected
     * @param eventType The accessibility event to send
     */
    @Override public void sendAccessibilityEvent(View host, int eventType)
    {
        if (eventType == AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUSED)
        {
            eventType = AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUS_CLEARED;
        }

        super.sendAccessibilityEvent(host, eventType);
    }

    /**
     * If the slider changes, it won't send the AccessibilityEvent TYPE_WINDOW_CONTENT_CHANGED
     * because it reads the percentages, so in that way it will read the sliderText.
     * On Android 10 and 9, the view got selected when it changes, so the TYPE_VIEW_SELECTED
     * event is controlled.
     *
     * @param host the view selected
     * @param event the accessibility event to send
     */
    @Override public void sendAccessibilityEventUnchecked(View host, AccessibilityEvent event)
    {
        if (event.getEventType() != AccessibilityEvent.TYPE_WINDOW_CONTENT_CHANGED
            && event.getEventType() != AccessibilityEvent.TYPE_VIEW_SELECTED)
        {
            super.sendAccessibilityEventUnchecked(host, event);
        }
    }
}

这样的话，我就可以选择seekbar，然后大声朗读，不带百分比。不要忘记附上活动搜索栏。OnSeekBarChangeListener到seekbar，以便在seekbar文本发生变化时更新它。

Answer 3

我在C#的Xamarin.Android中做了类似的事情，但代码应该足够容易移植回Java。此外，请记住，当控件突出显示时，这些更改将覆盖初始对讲。

首先在跟踪值集的text View上：

textView.AccessibilityLiveRegion = AndroidViews.AccessibilityLiveRegion.Assertive;

然后，我必须创建自己的自定义< code > AccessibilityDelegate :

public class CustomSeekbarDelegate : Android.Views.View.AccessibilityDelegate
{
    public override void OnInitializeAccessibilityEvent(AndroidViews.View host, AccessibilityEvent e)
    {
        //NOTE: Don't call base to prevent seekbar talkback percentage
    }
}

seekBar.SetAccessibilityDelegate(new CustomSeekbarDelegate());

可能有一种方法可以在第一次突出显示时保持初始语音控制的可访问性，但网上没有太多关于它的信息，这足以满足我们的需求。此外，我没有额外的时间来尝试让它也正常工作。