如何在JellyBean中检查Talkback是否处于活动状态

时间:2012-08-06 15:50:58

标签: android accessibility talkback android-4.1-jelly-bean

This question询问如何知道Android Talkback是否有效;直到果冻豆工作。从Android 4.1开始,该步骤不再有效,因为上述游标为空。

说完了,我想问一下是否有办法在Jelly Bean中进行相同的检查。

修改 我试图搜索TalkBack代码,我发现它here。 要检查TalkBack是否处于活动状态,我使用以下代码:

Intent screenReaderIntent = new Intent("android.accessibilityservice.AccessibilityService");
screenReaderIntent.addCategory("android.accessibilityservice.category.FEEDBACK_SPOKEN");
List<ResolveInfo> screenReaders = getPackageManager().queryIntentServices(screenReaderIntent, 0);
Cursor cursor = null;
ContentResolver cr = getContentResolver();
for (ResolveInfo screenReader : screenReaders) {
    cursor = cr.query(Uri.parse("content://" + screenReader.serviceInfo.packageName
            + ".providers.StatusProvider"), null, null, null, null);
    //here, cursor is not null, but calling cursor.moveToFirst() returns false, which means the cursor is empty
}

说完这个,如果光标为空,我们怎么知道TalkBack是否正在运行?

编辑2 根据@JoxTraex建议,我现在发送广播来查询是否启用了TalkBack:

Intent i = new Intent();
i.setAction("com.google.android.marvin.talkback.ACTION_QUERY_TALKBACK_ENABLED_COMMAND");
sendBroadcast(i);

现在我应该如何收到回复?

我尝试将以下内容添加到清单中,但我的收件人没有收到任何回复:

<receiver android:name="my.package.MyBroadcastReceiver"
android:permission="com.google.android.marvin.talkback.PERMISSION_SEND_INTENT_BROADCAST_COMMANDS_TO_TALKBACK">
<intent-filter>
    <action android:name="com.google.android.marvin.talkback.ACTION_QUERY_TALKBACK_ENABLED_COMMAND" />
</intent-filter>

4 个答案:

答案 0 :(得分:18)

使用AccessibilityManager可以更轻松地实现这一目标。

AccessibilityManager am = (AccessibilityManager) getSystemService(ACCESSIBILITY_SERVICE);
boolean isAccessibilityEnabled = am.isEnabled();
boolean isExploreByTouchEnabled = am.isTouchExplorationEnabled();

答案 1 :(得分:0)

在查看TalkBackService.java时,我发现了这些代码段。这些细分应提供有关如何查询状态的一些见解。

代码

/**
     * {@link Intent} broadcast action for querying the state of TalkBack. </p>
     * Note: Sending intent broadcast commands to TalkBack must be performed
     * through {@link Context#sendBroadcast(Intent, String)}
     */
    @Deprecated
    // TODO(caseyburkhardt): Remove when we decide to no longer support intent broadcasts for
    // querying the current state of TalkBack.
    public static final String ACTION_QUERY_TALKBACK_ENABLED_COMMAND = "com.google.android.marvin.talkback.ACTION_QUERY_TALKBACK_ENABLED_COMMAND";

    /**
     * Result that TalkBack is enabled.
     *
     * @see #ACTION_QUERY_TALKBACK_ENABLED_COMMAND
     */
    public static final int RESULT_TALKBACK_ENABLED = 0x00000001;

    /**
     * Result that TalkBack is disabled.
     *
     * @see #ACTION_QUERY_TALKBACK_ENABLED_COMMAND
     */
    public static final int RESULT_TALKBACK_DISABLED = 0x00000002;

    /**
     * Permission to send {@link Intent} broadcast commands to TalkBack.
     */
    public static final String PERMISSION_SEND_INTENT_BROADCAST_COMMANDS_TO_TALKBACK = "com.google.android.marvin.talkback.PERMISSION_SEND_INTENT_BROADCAST_COMMANDS_TO_TALKBACK";

    /**
     * Tag for logging.
     */
    private static final String LOG_TAG = "TalkBackService";

public static final String ACTION_QUERY_TALKBACK_ENABLED_COMMAND = "com.google.android.marvin.talkback.ACTION_QUERY_TALKBACK_ENABLED_COMMAND";
..

            } else if (ACTION_QUERY_TALKBACK_ENABLED_COMMAND.equals(intentAction)) {
            // TODO(caseyburkhardt): Remove this block when we decide to no
            // longer support
            // intent broadcasts for determining the state of TalkBack in
            // favor of the content
            // provider method.
            if (sInfrastructureInitialized) {
                setResultCode(RESULT_TALKBACK_ENABLED);
            } else {
                setResultCode(RESULT_TALKBACK_DISABLED);
            }
        }
            ...
    }

说明

您必须使用以下操作向TalkBackService发送Intent广播:

public static final String ACTION_QUERY_TALKBACK_ENABLED_COMMAND = "com.google.android.marvin.talkback.ACTION_QUERY_TALKBACK_ENABLED_COMMAND";

然后检查Extras的内容并相应地处理它。

ALSO 确保您拥有正确的权限:

public static final String PERMISSION_SEND_INTENT_BROADCAST_COMMANDS_TO_TALKBACK = "com.google.android.marvin.talkback.PERMISSION_SEND_INTENT_BROADCAST_COMMANDS_TO_TALKBACK";

答案 2 :(得分:0)

我不确定这是实现建议的最佳方式,但我设法通过使用以下代码来完成这项工作:

Intent screenReaderIntent = new Intent("android.accessibilityservice.AccessibilityService");
screenReaderIntent.addCategory("android.accessibilityservice.category.FEEDBACK_SPOKEN");
List<ResolveInfo> screenReaders = getPackageManager().queryIntentServices(screenReaderIntent, 0);
Cursor cursor = null;
int status = 0;
ContentResolver cr = getContentResolver();

List<String> runningServices = new ArrayList<String>();
ActivityManager manager = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
for (RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE)) {
    runningServices.add(service.service.getPackageName());
}

for (ResolveInfo screenReader : screenReaders) {
    cursor = cr.query(Uri.parse("content://" + screenReader.serviceInfo.packageName
            + ".providers.StatusProvider"), null, null, null, null);

    if (cursor != null && cursor.moveToFirst()) { //this part works for Android <4.1
        status = cursor.getInt(0);
        cursor.close();
        if (status == 1) {
            //screen reader active!
        } else {
            //screen reader inactive
        }
    } else {  //this part works for Android 4.1+
        if (runningServices.contains(screenReader.serviceInfo.packageName)) {
            //screen reader active!
        } else {
            //screen reader inactive
        }
    }
}

可能这不是最好的方法,但它是我能想到的唯一可以在Jelly Bean和以前的Android版本中运行的方式

答案 3 :(得分:0)

您可以检查已启用的语音访问服务器

fun Context.isScreenReaderEnabled(): Boolean {
    val accessibilityManager = getSystemService(Context.ACCESSIBILITY_SERVICE) as AccessibilityManager

    if (!accessibilityManager.isEnabled)
        return false

    val serviceInfoList = accessibilityManager.getEnabledAccessibilityServiceList(AccessibilityServiceInfo.FEEDBACK_SPOKEN)

    if (serviceInfoList.isNullOrEmpty())
        return false

    return true
}