Android FusedLocation 的 SettingsApi 不能多次工作

Question

FusedLocation 有一个很棒的 AP​​I 来检查用户是否启用了所有相关设置来获取位置。我遵循了文档 https://developers.google.com/android/reference/com/google/android/gms/location/SettingsApi启动 SettingsApi。我检查用户设置的代码如下

private void checkLocationSetting()
{
    if (mLocationSettingsRequest == null)
    {
        mLocationSettingsRequest =
                new LocationSettingsRequest.Builder()
                        .addLocationRequest(mLocationRequest)
                        .setAlwaysShow(true)
                        .build();
    }

    PendingResult<LocationSettingsResult> result =
            LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, mLocationSettingsRequest);

    result.setResultCallback(new ResultCallback<LocationSettingsResult>()
    {
        @Override
        public void onResult(LocationSettingsResult result)
        {
            final Status status = result.getStatus();
            final LocationSettingsStates state = result.getLocationSettingsStates();
            switch (status.getStatusCode())
            {
                case LocationSettingsStatusCodes.SUCCESS:
                {
                    // All location settings are satisfied. The client can initialize location
                    // requests here.
                    requestNewLocationBySettingLocationReq();
                    break;
                }
                case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
                {
                    // Location settings are not satisfied. But could be fixed by showing the user
                    // a dialog.
                    try
                    {
                        // Show the dialog by calling startResolutionForResult(),
                        // and check the result in onActivityResult().
                        status.startResolutionForResult(SpotToiletMap.this, REQUEST_CHECK_SETTINGS);
                    } catch (IntentSender.SendIntentException e)
                    {
                        // Ignore the error.
                    }
                    break;
                }
                case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                {
                    // Location settings are not satisfied. However, we have no way to fix the
                    // settings so we won't show the dialog.
                    MiscellaneousMethods.showGenericSnackBar(rootView, getString(R.string.location_settings_unavailable));
                    break;
                }
            }
        }
    });
}

这段代码第一次工作得很好。随后，PendingResult CallBack 从未起作用。我也无法在 logcat 上找到任何日志。对我来说，这看起来像是一个实现问题。

这是重现问题的方法。

关闭您的 GPS。尝试调用该方法，它按预期完美运行。它要求我切换 n GPS。收到位置更新后，再次关闭 GPS 并调用此方法。我从未收到启用 GPS 的对话框。我在尝试获取用户的最新位置的按钮单击时调用此方法。

编辑:我试图将 PendingResult 结果声明为类变量。仍然没有运气。我还尝试通过检查结果是否为空来仅初始化一次结果，正如预期的那样，正如谷歌文档中提到的那样，它会抛出一个异常，指出结果已被使用。

Answer 1

看起来问题在于您不是每次都重新创建 LocationSettingsRequest.Builder，因为您只有在它为 null 时才重新创建它。

我让它工作了，在 Android 4.4.4 和 6.0.1 上进行了测试。

每次按下按钮时都会显示对话框(前提是在两次按下按钮之间的设备上禁用了位置):

public void checkLocationSetting() {
    mLocationRequest = LocationRequest.create();
    mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
    mLocationRequest.setInterval(30 * 1000);
    mLocationRequest.setFastestInterval(5 * 1000);

    LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
            .addLocationRequest(mLocationRequest);
    builder.setAlwaysShow(true);

    result = LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, builder.build());

    result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
        @Override
        public void onResult(LocationSettingsResult result) {
            final Status status = result.getStatus();
            switch (status.getStatusCode()) {
                case LocationSettingsStatusCodes.SUCCESS:
                    // All location settings are satisfied. The client can initialize location
                    // requests here.
                    //...
                    break;
                case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
                    // Location settings are not satisfied. But could be fixed by showing the user
                    // a dialog.
                    try {
                        // Show the dialog by calling startResolutionForResult(),
                        // and check the result in onActivityResult().
                        status.startResolutionForResult(
                                MainActivity.this,
                                REQUEST_LOCATION);
                    } catch (IntentSender.SendIntentException e) {
                        // Ignore the error.
                    }
                    break;
                case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                    // Location settings are not satisfied. However, we have no way to fix the
                    // settings so we won't show the dialog.
                    //...
                    break;
            }
        }
    });

}