firebase - Flutter Firebase 中的喜欢和不喜欢的功能

Question

我正在尝试使用 Firebase 在颤振上构建类似的功能。我能够使用事务存储和删除类似的东西。我坚持的是，我怎样才能在前端表示类似的状态？

(_isLiked == false)
        ? IconButton(
            iconSize: Sizes.s35,
            color: Colors.black,
            icon: Icon(Icons.favorite_outline),
            onPressed: () {
              setState(() {
                _isLiked = true;
                final like = LikeData(
                  campaingID: donation.campaignID,
                  dateTime: Timestamp.now(),
                  userId: user.uid,
                  likeId: DateTime.now().toString(),
                  like: _isLiked,
                );
                likeService.newLike(donation, like);
              });
            },
          )
        : IconButton(
            iconSize: Sizes.s35,
            color: Colors.green,
            icon: Icon(Icons.favorite),
            onPressed: () {
              setState(() {
                likeService.deleteLike(donation, user);
              });
            },
          ),

这就是我现在将它表示为硬编码_isliked 布尔值的方式。如何从 Firebase 调用状态？

标签： firebaseflutterfirebase-realtime-databasegoogle-cloud-firestore

Answer 1

您可能需要添加一个 StreamBuilder 来收听喜欢/不喜欢的实时变化，我已经为您提供了以下解决方案。

Widget likeWidget(String postId) {
return Column(
  children: [
    SizedBox(
      height: Get.height * 0.022,
      width: Get.width * .15,
      child: StreamBuilder(
          stream: FBCollections.postLikes
              .where("post_id", isEqualTo: postId)
              .where("user_id", isEqualTo: userData.userEmail)
              .snapshots(),
          builder:
              (context, AsyncSnapshot<QuerySnapshot> snapshotCheckLike) {
            if (!snapshotCheckLike.hasData) {
              return Container();
            } else {
              return snapshotCheckLike.data.docs.isEmpty
                  ? IconButton(
                      icon: Icon(Icons.favorite_outline),
                      onPressed: () {
                        final like = LikeData(
                          campaingID: donation.campaignID,
                          dateTime: Timestamp.now(),
                          userId: user.uid,
                          likeId: DateTime.now().toString(),
                          like: true,
                        );
                        likeService.newLike(donation, like);
                      },
                    )
                  : IconButton(
                      iconSize: Sizes.s35,
                      color: Colors.green,
                      icon: Icon(Icons.favorite),
                      onPressed: () {
                        setState(() {
                          likeService.deleteLike(donation, user);
                        });
                      },
                    );
            }
          }),
    ),
  ],
);

}