java - 接收位置请求时，LocationSettingsStates类做什么？

在文档here中，我关注如何接收位置请求，并且在这两个代码块中发现了两个不寻常的事情：

result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
     @Override
     public void onResult(LocationSettingsResult result) {
         final Status status = result.getStatus();
         final LocationSettingsStates = result.getLocationSettingsStates(); //<--This line I don't understand
         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(
                         OuterClass.this,
                         REQUEST_CHECK_SETTINGS);
                 } catch (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;
         }
     }
 });

在第二个块中：

@Override
 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
     final LocationSettingsStates states = LocationSettingsStates.fromIntent(intent);  //<--And this line
     switch (requestCode) {
         case REQUEST_CHECK_SETTINGS:
             switch (resultCode) {
                 case Activity.RESULT_OK:
                     // All required changes were successfully made
                     ...
                     break;
                 case Activity.RESULT_CANCELED:
                     // The user was asked to change settings, but chose not to
                     ...
                     break;
                 default:
                     break;
             }
             break;
     }
 }

我添加了一些箭头，指向我不理解的线。特别是这两个：

final LocationSettingsStates = result.getLocationSettingsStates();

final LocationSettingsStates states = LocationSettingsStates.fromIntent(intent);

第一行是我之前从未见过的东西。将值分配给数据类型如何有效？然后，该类不再在该代码块的其他任何地方使用，那么赋值的目的是什么？

在另一行中，现在它将为该数据类型的称为states的实例分配一个值，但该实例在onActivityResult()中的其他任何地方都没有使用。

那么这是怎么回事？谢谢。

最佳答案

第一行肯定是拼写错误；它应该是这样的：

final LocationSettingsStates states = result.getLocationSettingsStates();

是的，这两个地方都没有使用它，这很奇怪，但是您可以像isBleUsable()一样调用things来确定确切存在的内容和当前可用的内容。在后一种情况下，这是尝试解决后可用的功能。

关于java - 接收位置请求时，LocationSettingsStates类做什么？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/37242018/