如何通過檢索上傳到Firebase數據庫或存儲的Image，TextViews來設置活動的ImageView，TextViews？

Question

我正在創建一個新的android應用程序，該應用程序檢索一個圖像，使用不同的或說管理應用程序已上載到firebase的兩個文本，並且上載的圖像和文本視圖將被檢索到一個卡視圖中，如圖所示。 現在，它在recyclerview中，我希望它像任何其他博客應用程序一樣。因此，當用戶單擊該卡片視圖，imageview，標題時，所有這些視圖將按照默認布局排列，如圖所示在下面的圖像中。我的意思是將圖像視圖設置為從Firebase檢索到的圖像，並將兩個文本視圖都設置為從Firebase檢索到的文本。因此，當任何用戶單擊從Firebase檢索到的任何博客帖子時，都應打開該默認布局並且所有視圖將轉到聲明的位置。如何實現此目標？ 我用來在cardview中檢索和顯示內容的代碼如下。由於我是stackoverflow的新手，所以我沒有足夠的聲譽來添加圖像。請通過下面的圖像鏈接。 圖片一https://ibb.co/kJtvNTm

https://ibb.co/KXB8fdj

這是出於我自己的教育目的，我是開發android應用程序和firebase的新手。我曾嘗試檢索它們，但並沒有將它們放置在原處的意願。

PostRecyclerActivity.java

    private RecyclerView mRecyclerView;
    private PostImageAdapter mAdapter;

    private ProgressBar mProgressCircle;

    private DatabaseReference mDatabaseRef;
    private List<PostUpload> mUploads;

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

        mRecyclerView = findViewById(R.id.post_recycler_view);
        mRecyclerView.setHasFixedSize(true);
        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));

        mProgressCircle = findViewById(R.id.post_progress_circle);

        mUploads = new ArrayList<>();

        mDatabaseRef = FirebaseDatabase.getInstance().getReference("posts");

        mDatabaseRef.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                for (DataSnapshot postSnapshot : dataSnapshot.getChildren()) {
                    PostUpload upload = postSnapshot.getValue(PostUpload.class);
                    mUploads.add(upload);
                }

                mAdapter = new PostImageAdapter(PostImageRecyclerActivity.this, mUploads);

                mRecyclerView.setAdapter(mAdapter);
                mProgressCircle.setVisibility(View.INVISIBLE);
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {
                Toast.makeText(PostImageRecyclerActivity.this, databaseError.getMessage(), Toast.LENGTH_SHORT).show();
                mProgressCircle.setVisibility(View.INVISIBLE);
            }
        });
    }
}

PostImageAdapter.java

public class PostImageAdapter extends RecyclerView.Adapter<PostImageAdapter.ImageViewHolder> {
    private Context mContext;
    private List<PostUpload> mUploads;

    public PostImageAdapter(Context context, List<PostUpload> uploads) {
        mContext = context;
        mUploads = uploads;
    }

    @Override
    public ImageViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(mContext).inflate(R.layout.post_card, parent, false);
        return new ImageViewHolder(v);
    }

    @Override
    public void onBindViewHolder(ImageViewHolder holder, int position) {
        PostUpload uploadCurrent = mUploads.get(position);
        holder.textViewName.setText(uploadCurrent.getHeading());
        Picasso.get()
                .load(uploadCurrent.getmImageUrl())
                .fit()
                .centerCrop()
                .into(holder.imageView);
    }

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

    public class ImageViewHolder extends RecyclerView.ViewHolder {
        public TextView textViewName;
        public ImageView imageView;

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

            textViewName = itemView.findViewById(R.id.text_view_name);
            imageView = itemView.findViewById(R.id.post_image_view_upload);
        }
    }
}

PostUpload.java

public class PostUpload {

    private String mHeading;
    private String mMatter;
    private String mImageUrl;

    public PostUpload() {
    }

    public PostUpload(String heading, String matter, String imageUrl) {
        if (heading.trim().equals("")) {

            heading = "No Name";
        }
        mHeading = heading;
        mMatter = matter;
        mImageUrl = imageUrl;

    }

    public String getHeading(){
        return mHeading;
    }
    public void setHeading(String name){
        mHeading=name;
    }
    public String getMatter(){
        return mMatter;
    }
    public void setMatter(String name){
        mMatter=name;
    }
    public String getmImageUrl(){
        return mImageUrl;
    }
    public  void setImageUrl(String imageUrl){
        mImageUrl=imageUrl;
    }
}

我希望單擊博客文章后的輸出應該將圖像和標題設置在如圖2所示的位置，然后從firebase檢索問題並將其設置到另一個文本視圖中，如圖2所示。

Answer 1

當你正在從火力地堡中的數據，你在你的存放mUploads類型的數組PostUpload要顯示到這些數據CardViews

這里

 mDatabaseRef.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                for (DataSnapshot postSnapshot : dataSnapshot.getChildren()) {
                    PostUpload upload = postSnapshot.getValue(PostUpload.class);
                    mUploads.add(upload);
                }

                mAdapter = new PostImageAdapter(PostImageRecyclerActivity.this, mUploads);

                mRecyclerView.setAdapter(mAdapter);
                mProgressCircle.setVisibility(View.INVISIBLE);
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {
                Toast.makeText(PostImageRecyclerActivity.this, databaseError.getMessage(), Toast.LENGTH_SHORT).show();
                mProgressCircle.setVisibility(View.INVISIBLE);
            }
        });

當您點擊mRecyclerView.setAdapter(mAdapter); 您已經填寫了數組並將信息顯示給用戶。

之后，您可以使用適配器中的getItem() 。

您只需要在PostImageAdapter重寫該方法

public PostUpload getItem(int position) {
  return mUploads.get(position);
}

一旦有了此方法，就可以從PostRecyclerActivity.java從Firebase填充的數組中訪問任何項目。

因此，在您的RecyclerView中單擊一個項目后，您可以獲取位置並從該位置獲取對象信息

這是實現點擊recyclerview的每一行的許多好方法（我建議第一行）

因此，在實現recyclerview中每一行的點擊之后，只需將該數據通過捆綁包或其他方式傳遞給其他活動

偽代碼示例

recyclerView.onClick{...
  public void recyclerViewListClicked(View v, int position){
    if(mAdapter.getItemCount() > 0){
    PostUpload post = mAdapter.getItem(position);
    }else{
     Toast("There is no data into the element");
    }

 //Go to another Activity
  Intent intent = new Intent(PostRecyclerActivity.this,yourSecondActivity.class);
  intent.putExtra(post.getHeadding,"postheading");
  intent.putExtra(post.getMatter,"postmatter");
  //You keep doing the same with the other data you need to send out.
  startActivity(intent);
}

如何從Activity2中獲取數據

Intent intent = getIntent();
String postheading = intent.getStringExtra("postheading");
String postmatter = intent.getStringExtra("postmatter");

由於圖像是String類型的URL，只需像intent.putExtra()一樣將其作為intent.putExtra()傳遞即可，您可以從其他Activity中獲取該URL並為圖像充氣。