如何在Android中从Google Calendar中获取今天的事件

在Android中，可以通过使用Google Calendar API来从Google Calendar中获取今天的事件。以下是一种实现方法：

首先，确保你的Android项目已经添加了Google Play服务库的依赖。可以在项目的build.gradle文件中添加以下依赖项：

implementation 'com.google.android.gms:play-services-calendar:17.0.0'

在Google开发者控制台中创建一个项目，并启用Google Calendar API。获取API密钥和客户端ID。
在AndroidManifest.xml文件中添加以下权限：

<uses-permission android:name="android.permission.READ_CALENDAR" />
<uses-permission android:name="android.permission.WRITE_CALENDAR" />

在代码中，使用以下方法来获取今天的事件：

import com.google.api.client.googleapis.extensions.android.gms.auth.GoogleAccountCredential;
import com.google.api.client.googleapis.extensions.android.gms.auth.UserRecoverableAuthIOException;
import com.google.api.client.util.DateTime;
import com.google.api.services.calendar.Calendar;
import com.google.api.services.calendar.CalendarScopes;
import com.google.api.services.calendar.model.Event;
import com.google.api.services.calendar.model.Events;

import java.io.IOException;
import java.util.Arrays;
import java.util.List;

public class CalendarHelper {
    private static final String[] SCOPES = {CalendarScopes.CALENDAR_READONLY};
    private static final String APPLICATION_NAME = "Your Application Name";

    public static List<Event> getTodayEvents(GoogleAccountCredential credential) throws IOException {
        Calendar service = new Calendar.Builder(AndroidHttp.newCompatibleTransport(), new GsonFactory(), credential)
                .setApplicationName(APPLICATION_NAME)
                .build();

        DateTime now = new DateTime(System.currentTimeMillis());
        DateTime todayStart = new DateTime(now.getValue(), now.getTimeZone());
        todayStart.set("00:00:00");
        DateTime todayEnd = new DateTime(now.getValue(), now.getTimeZone());
        todayEnd.set("23:59:59");

        Events events = service.events().list("primary")
                .setTimeMin(todayStart)
                .setTimeMax(todayEnd)
                .setOrderBy("startTime")
                .setSingleEvents(true)
                .execute();

        return events.getItems();
    }
}

在你的Activity或Fragment中，使用以下代码来获取今天的事件：

import com.google.api.client.googleapis.extensions.android.gms.auth.GoogleAccountCredential;
import com.google.api.client.googleapis.extensions.android.gms.auth.UserRecoverableAuthIOException;
import com.google.api.services.calendar.model.Event;

import java.io.IOException;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private static final int REQUEST_ACCOUNT_PICKER = 1000;
    private static final int REQUEST_AUTHORIZATION = 1001;

    private GoogleAccountCredential credential;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        credential = GoogleAccountCredential.usingOAuth2(this, Arrays.asList(CalendarScopes.CALENDAR_READONLY));
        startActivityForResult(credential.newChooseAccountIntent(), REQUEST_ACCOUNT_PICKER);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == REQUEST_ACCOUNT_PICKER && resultCode == RESULT_OK) {
            String accountName = data.getStringExtra(AccountManager.KEY_ACCOUNT_NAME);
            credential.setSelectedAccountName(accountName);

            new GetEventsTask().execute();
        } else if (requestCode == REQUEST_AUTHORIZATION && resultCode == RESULT_OK) {
            new GetEventsTask().execute();
        }
    }

    private class GetEventsTask extends AsyncTask<Void, Void, List<Event>> {
        private Exception exception;

        @Override
        protected List<Event> doInBackground(Void... voids) {
            try {
                return CalendarHelper.getTodayEvents(credential);
            } catch (UserRecoverableAuthIOException e) {
                startActivityForResult(e.getIntent(), REQUEST_AUTHORIZATION);
                return null;
            } catch (IOException e) {
                exception = e;
                return null;
            }
        }

        @Override
        protected void onPostExecute(List<Event> events) {
            super.onPostExecute(events);

            if (events != null) {
                // 处理获取到的事件列表
            } else if (exception != null) {
                // 处理异常情况
            }
        }
    }
}

这样，你就可以使用Google Calendar API在Android中获取今天的事件了。请注意，上述代码仅提供了基本的实现思路，实际使用时可能需要根据具体需求进行适当修改和完善。