单击 Cardview 时如何在另一个活动中显示详细信息

Question

我遇到了问题，如何根据位置显示cardView的值？ 我觉得我有点错过了什么。

这是我的代码

    @Override
    public void onBindViewHolder(AnnouncementViewHolder holder, int position) {
        AnnouncementModel announcement = announcementList.get(position);

        if (announcement.getImage()!=null && !announcement.getImage().isEmpty()){
            Picasso.get()
                    .load(announcement.getImage())
                    // To fit image into imageView
                    .fit()
                    // To prevent fade animation
                    .noFade()
                    .into(holder.imageView);
        }else{
            //Do nothing
        }

        holder.textViewDate.setText(announcement.getDate());
        holder.textViewTitle.setText(announcement.getTitle());
        holder.textViewExcerpt.setText(announcement.getExcerpt());

    }

    @Override
    public int getItemCount() {
        return announcementList.size();
    }

    class AnnouncementViewHolder extends RecyclerView.ViewHolder {

        TextView textViewTitle, textViewExcerpt,textViewDate;
        ImageView imageView;

        public AnnouncementViewHolder(View itemView) {
            super(itemView);

            textViewDate = itemView.findViewById(R.id.textAnnouncementDate);
            textViewTitle = itemView.findViewById(R.id.textAnnouncementDesc);
            textViewExcerpt = itemView.findViewById(R.id.textAnnouncementDesc);
            imageView = itemView.findViewById(R.id.AnnouncementImageView);

            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Context context = v.getContext();
                    Intent intent = new Intent(context, DetailActivityAnnouncement.class);
                    intent.putExtra(DetailActivity.EXTRA_POSITION, getAdapterPosition());
                    context.startActivity(intent);
                }
            });

        }
    }

我想在单击时向我的其他活动显示textViewDate和textViewTitle 。

这是我的detailActvity

public class DetailActivity extends AppCompatActivity {


    public static final String EXTRA_POSITION = "position";
    AnnouncementModel model;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_detail_announcement);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);


        int postion = getIntent().getIntExtra(EXTRA_POSITION, 0);

        TextView announcementContent = (TextView) findViewById(R.id.textAnnouncementContext);
        TextView announcementDate = (TextView) findViewById(R.id.textAnnouncementDate);
        ImageView announcementImage = (ImageView) findViewById(R.id.AnnouncementImageView);
        TextView announcementOtherDetails = (TextView) findViewById(R.id.textAnnouncementOtherDetails);


    }

}

我觉得我已经接近我的答案了，但我仍然被困住了。 任何帮助将非常感激。

Answer 1

您可以使用意图将数据从一个活动发送到另一个活动。

在您的itemView.setOnClickListener()您已经定义了打开DetailActivity的 Intent 。

现在您需要做的就是添加带有意图的数据，例如

Context context = v.getContext();
Intent intent = new Intent(context, DetailActivityAnnouncement.class);
intent.putExtra(DetailActivity.EXTRA_POSITION, getAdapterPosition());

// putExtra can be used to send data with intent, here "date"
// and "title" is key that we will need later to access these values 
intent.putExtra("date",announcementList.get(getAdapterPosition()).getDate());
intent.putExtra("title", announcementList.get(getAdapterPosition()).getTitle());

context.startActivity(intent);

在您的DetailActivity您可以在onCreate方法中检索此信息

@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_detail_announcement);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);


        int postion = getIntent().getIntExtra(EXTRA_POSITION, 0);

        //you can retrieve data from intent like
        String textViewDate = getIntent().getStringExtra("date");
        String textViewTitle = getIntent().getStringExtra("title");

        TextView announcementContent = (TextView) findViewById(R.id.textAnnouncementContext);
        TextView announcementDate = (TextView) findViewById(R.id.textAnnouncementDate);
        ImageView announcementImage = (ImageView) findViewById(R.id.AnnouncementImageView);
        TextView announcementOtherDetails = (TextView) findViewById(R.id.textAnnouncementOtherDetails);


    }

额外：-您应该始终检查您是否已从意图接收数据，并确保textViewDate, textViewTitle不为空。

您还可以在检索活动中的数据之前进行检查，例如if(getIntent().hasExtra("date"))如果您有数据，那么它将为真。

Answer 2

我认为，而不是仅将位置传递给详细信息活动，您应该尝试在意图中传递日期和标题（而不仅仅是位置），然后将它们都放在详细活动中以显示它，或者您可以使您的公告对象可打包，然后将它传递给意图本身，这样您就可以获得所有详细信息。 您可以使用标签设置为ItemView控件itemView.setTag()然后让使用对象itemView.getTag()

Answer 3

我建议你做一个接口

public interface DeviceClickedInterface {
void DeviceSelectedInterface(int position);
}

并在您的 Adapter 中将其传递给 Class

private DeviceClickedInterface deviceClickedInterface;

public DevicesAdapter( DeviceClickedInterface deviceClickedInterface, ... the rest of params.) {
    //other params. init.
    this.deviceClickedInterface = deviceClickedInterface;
}

使AnnouncementViewHolder包含itemView为孩子过了，里面onBindViewHolder附加ClickListener在itemView

        holder.itemView.setOnClickListener(v -> deviceClickedInterface.DeviceSelectedInterface(position));

最后使DetailActivity实现您自己的DeviceClickedInterface它将覆盖您的 Activity 中的DeviceSelectedInterface方法，该方法将在您每次单击CardView时返回位置