Question

运行此代码时，加载进度条后Apps崩溃。使用该代码，我试图在卡片视图中显示Firebase中的图像。一切正常，直到从数据库完全加载图像后我添加代码以隐藏进度栏。

请提出一些在我的代码中实现的方法，以便在从数据库中完全加载图像时删除进度条

package com.example.ananthu.currentaffairs;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

import com.bumptech.glide.Glide;
import com.bumptech.glide.annotation.GlideModule;
import com.bumptech.glide.module.AppGlideModule;
import com.firebase.ui.database.FirebaseRecyclerAdapter;
import com.firebase.ui.database.FirebaseRecyclerOptions;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.Query;
import com.squareup.picasso.Callback;
import com.squareup.picasso.Picasso;
import android.app.ProgressDialog;
import android.view.Window;
import android.view.WindowManager;




public class NewsActivity extends AppCompatActivity {



    private ProgressBar progressBar;



    private RecyclerView mPeopleRV;
    private DatabaseReference mDatabase;
    private FirebaseRecyclerAdapter<News, NewsActivity.NewsViewHolder> mPeopleRVAdapter;








    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_news);
        progressBar = (ProgressBar)findViewById(R.id.pro);



        progressBar.setVisibility(View.VISIBLE);



        setTitle("News");

        //"News" here will reflect what you have called your database in Firebase.
        mDatabase = FirebaseDatabase.getInstance().getReference().child("News");
        mDatabase.keepSynced(true);

        mPeopleRV = (RecyclerView) findViewById(R.id.myRecycleView);

        DatabaseReference personsRef = FirebaseDatabase.getInstance().getReference().child("News");
        Query personsQuery = personsRef.orderByKey();

        mPeopleRV.hasFixedSize();
        mPeopleRV.setLayoutManager(new LinearLayoutManager(this));

        FirebaseRecyclerOptions personsOptions = new FirebaseRecyclerOptions.Builder<News>().setQuery(personsQuery, News.class).build();

        mPeopleRVAdapter = new FirebaseRecyclerAdapter<News, NewsActivity.NewsViewHolder>(personsOptions) {
            @Override
            protected void onBindViewHolder(NewsActivity.NewsViewHolder holder, final int position, final News model) {

                holder.setImage(getBaseContext(), model.getImage());





                }



            @Override
            public NewsActivity.NewsViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {


                View view = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.news_row, parent, false);

                return new NewsActivity.NewsViewHolder(view);



            }
        };

        mPeopleRV.setAdapter(mPeopleRVAdapter);

    }


    @Override
    public void onStart() {
        super.onStart();
        mPeopleRVAdapter.startListening();

    }

    @Override
    public void onStop() {
        super.onStop();
        mPeopleRVAdapter.stopListening();




    }



    public static class NewsViewHolder extends RecyclerView.ViewHolder{
        private ProgressBar progressBar;

        View mView;
        public NewsViewHolder(View itemView){
            super(itemView);
            mView = itemView;

        }


        public void setImage(Context ctx, String image){
            ImageView post_image = (ImageView) mView.findViewById(R.id.post_image);

            Picasso.with(ctx).load(image).into(post_image,new Callback() {
                @Override// This the place where problem occcurs
                public void onSuccess() {
                    progressBar.setVisibility(View.GONE);
                }

                @Override
                public void onError() {

                }
            });


        }



    }
}
[The image shows the Logcat when I run the code][1]


  [1]: https://i.stack.imgur.com/5uP4n.png

Answer 1

不需要NewsViewHolder类中的进度条您可以像下面的代码一样使用静态进度栏：

    import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.ProgressBar;

import com.firebase.ui.database.FirebaseRecyclerAdapter;
import com.firebase.ui.database.FirebaseRecyclerOptions;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.Query;
import com.squareup.picasso.Callback;
import com.squareup.picasso.Picasso;

import ir.pofelak.dialer.R;


public class NewsActivity extends AppCompatActivity {



    public static ProgressBar progressBar;



    private RecyclerView mPeopleRV;
    private DatabaseReference mDatabase;
    private FirebaseRecyclerAdapter<News, NewsActivity.NewsViewHolder> mPeopleRVAdapter;








    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_news);
        progressBar = (ProgressBar)findViewById(R.id.pro);



        progressBar.setVisibility(View.VISIBLE);



        setTitle("News");

        //"News" here will reflect what you have called your database in Firebase.
        mDatabase = FirebaseDatabase.getInstance().getReference().child("News");
        mDatabase.keepSynced(true);

        mPeopleRV = (RecyclerView) findViewById(R.id.myRecycleView);

        DatabaseReference personsRef = FirebaseDatabase.getInstance().getReference().child("News");
        Query personsQuery = personsRef.orderByKey();

        mPeopleRV.hasFixedSize();
        mPeopleRV.setLayoutManager(new LinearLayoutManager(this));

        FirebaseRecyclerOptions personsOptions = new FirebaseRecyclerOptions.Builder<News>().setQuery(personsQuery, News.class).build();

        mPeopleRVAdapter = new FirebaseRecyclerAdapter<News, NewsActivity.NewsViewHolder>(personsOptions) {
            @Override
            protected void onBindViewHolder(NewsActivity.NewsViewHolder holder, final int position, final News model) {

                holder.setImage(getBaseContext(), model.getImage());





            }



            @Override
            public NewsActivity.NewsViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {


                View view = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.news_row, parent, false);

                return new NewsActivity.NewsViewHolder(view);



            }
        };

        mPeopleRV.setAdapter(mPeopleRVAdapter);

    }


    @Override
    public void onStart() {
        super.onStart();
        mPeopleRVAdapter.startListening();

    }

    @Override
    public void onStop() {
        super.onStop();
        mPeopleRVAdapter.stopListening();




    }



    public static class NewsViewHolder extends RecyclerView.ViewHolder{

        View mView;
        public NewsViewHolder(View itemView){
            super(itemView);
            mView = itemView;

        }


        public void setImage(Context ctx, String image){
            ImageView post_image = (ImageView) mView.findViewById(R.id.post_image);

            Picasso.with(ctx).load(image).into(post_image,new Callback() {
                @Override// This the place where problem occcurs
                public void onSuccess() {
                    progressBar.setVisibility(View.GONE);
                }

                @Override
                public void onError() {

                }
            });


        }

尝试隐藏进度条时应用崩溃

1 个答案: