Question

我正在尝试使用AccessibilityManager和TalkBack触发自定义AccessibilityEvent。

事件的用例是当用户单击操作栏时，片段轮询对象列表，然后根据列表的大小简化其AccessibilityEvent内容。

当我尝试运行时，我没有得到预期的TalkBack消息。我很确定我缺少一些基本的实例化AccessibilityEvent。

我也不确定我是否需要使用，或者如何在此处应用AccessibilityDelegate，因为回调来自MenuItem而不是View。我知道我可以调用findViewById来获取这个MenuItem的视图，但我对这些API知之甚少。

关于这两点的任何指导都会很棒！

有问题的问题基本上由以下伪代码描述：

public class MyFragment extends Fragment {

//...

private List<Pojo> mPojoList;

//...

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if (item.getItemId() == R.id.the_id_for_my_menuitem) {
        if (booleanCheck() && !mPojoList.isEmpty()) {

            //create the Accessibility event
            final AccessibilityEvent event = AccessibilityEvent.obtain(AccessibilityEvent.TYPE_VIEW_CLICKED);
            event.setContentDescription(String.format("deleting %2d pojos", mPojoList.size()));

            //Send a custom accessibility event to let the user know that we're deleting X objects.
            final AccessibilityManager mgr = (AccessibilityManager) this.getActivity().getSystemService(Context.ACCESSIBILITY_SERVICE);

            //PROBLEM: We're not seeing this event come through in TalkBack.
            mgr.sendAccessibilityEvent(event);

            //Delete the objects.
            myDeleteObjectsFunction();
        }
    }
}}

Answer 1

尝试使用View对象触发辅助功能事件。

AccessibilityEvent event = AccessibilityEvent.obtain(AccessibilityEvent.TYPE_VIEW_CLICKED);
event.setContentDescription(String.format("deleting %2d pojos", mPojoList.size()));

View view = getActivity().findViewById(R.id.child_view);

ViewParent parent = view.getParent();
if (parent != null) {
  parent.requestSendAccessibilityEvent(view, event);
}

Answer 2

虽然这是一个老问题，但我会发表我的答案，因为之前给出的答案对我不起作用。

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if (item.getItemId() == R.id.the_id_for_my_menuitem) {
        if (booleanCheck() && !mPojoList.isEmpty()) {

            AccessibilityManager manager = (AccessibilityManager)this.getSystemService(Context.ACCESSIBILITY_SERVICE);
            if(manager.isEnabled()){
                AccessibilityEvent event = AccessibilityEvent.obtain();
                event.setEventType(AccessibilityEvent.TYPE_ANNOUNCEMENT);
                event.setClassName(getClass().getName());
                event.getText().add(*yourString*);

                if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
                    event.setSource(findViewById(*yourButton*));
                }
                manager.sendAccessibilityEvent(event);
            }
        }
    }
}

Android从ActionBar按钮单击启动自定义辅助功能事件

2 个答案: