Android：我可以在不将用户重定向到“谷歌地图”应用程序中的设置屏幕的情况下启用 GPS

Question

在基于 GPS 的应用程序中，用户启用他的 GPS 非常重要。如果不是，那么通常我们会显示一个对话框，说明用户“应该从设置中启用他的 GPS 才能使用此功能”。

当用户按下 OK 时，他将被重定向到设置页面，我不喜欢这种解决方案，因为它会将用户带出应用程序上下文进入设置。

我注意到“谷歌地图”应用程序有一个更好的解决方案，即在需要 GPS 功能时显示一个简洁的对话框。用户选择“OK”后，GPS 将直接启用，无需任何重定向到设置。

我可以在不将用户重定向到“谷歌地图”应用程序中的设置屏幕的情况下启用 GPS 吗？

查看下图：

Answer 1

要拥有您需要的功能：

• 首先（至少）7.0 版的播放服务

compile 'com.google.android.gms:play-services-location:16.0.0'

• 在您的代码中第二个类似这样的内容（我的 onCreate 中有它）：

-

 // Check the location settings of the user and create the callback to react to the different possibilities
LocationSettingsRequest.Builder locationSettingsRequestBuilder = new LocationSettingsRequest.Builder()
                .addLocationRequest(mLocationRequest);
PendingResult<LocationSettingsResult> result =
                LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, locationSettingsRequestBuilder.build());
result.setResultCallback(mResultCallbackFromSettings);

然后创建回调：

// The callback for the management of the user settings regarding location
private ResultCallback<LocationSettingsResult> mResultCallbackFromSettings = new ResultCallback<LocationSettingsResult>() {
    @Override
    public void onResult(LocationSettingsResult result) {
        final Status status = result.getStatus();
        //final LocationSettingsStates locationSettingsStates = result.getLocationSettingsStates();
        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(
                            MapActivity.this,
                            REQUEST_CHECK_SETTINGS);
                } catch (IntentSender.SendIntentException e) {
                    // Ignore the error.
                }
                break;
            case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                Log.e(TAG, "Settings change unavailable. We have no way to fix the settings so we won't show the dialog.");
                break;
        }
    }
};

最后，在onActivityResult 中，我得到了以下信息：

/**
 * Used to check the result of the check of the user location settings
 *
 * @param requestCode code of the request made
 * @param resultCode code of the result of that request
 * @param intent intent with further information
 */
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
    //final LocationSettingsStates states = LocationSettingsStates.fromIntent(intent);
    switch (requestCode) {
        case REQUEST_CHECK_SETTINGS:
            switch (resultCode) {
                case Activity.RESULT_OK:
                    // All required changes were successfully made
                    if (mGoogleApiClient.isConnected() && userMarker == null) {
                        startLocationUpdates();
                    }
                    break;
                case Activity.RESULT_CANCELED:
                    // The user was asked to change settings, but chose not to
                    break;
                default:
                    break;
            }
            break;
    }
}