java - 将图像加载到滚动 Activity 时出现内存不足错误

Question

我想在滚动 Activity 中显示 90 张图像，前 20 张图像显示没有问题，但当我向下滚动时，应用程序立即关闭 所以我只想显示前 20 个对象，然后当用户向下滚动时我会销毁第一行并创建一个新行，依此类推，这样机器就不必一次加载所有 90 个对象

这是我的代码:

ArrayList<Hero> heroes;
SearchView searchView;
GridAdapter gridAdapter;
String[] names = {"Akai","(and 90 more Strings)" };

Integer[] images = {R.drawable.akai , (and 90 more Images) };

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_heroes);
    CreateList();
    GridView gridView = findViewById(R.id.gridView);
    gridAdapter = new GridAdapter(this, heroes);
    gridView.setAdapter(gridAdapter);
    gridView.setNumColumns(4);
    searchView = (SearchView) findViewById(R.id.search_view);
    searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
        @Override
        public boolean onQueryTextSubmit(String query) {
            return false;
        }

        @Override
        public boolean onQueryTextChange(String newText) {
            gridAdapter.getFilter().filter(newText);
            return false;
        }
    });
    gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            Intent toAtt = new Intent(getApplication(),HeroAttributes.class);
            toAtt.putExtra("item",heroes.get(position).getButton());
            startActivity(toAtt);
        }
    });
}
public void CreateList() {
    heroes = new ArrayList<>();
    for (int i=0 ; i<names.length ; i++) {
        Hero hero = new Hero(images[i] , names[i]);
        heroes.add(hero);
    }
}

我的GridAdapter代码:

    public class GridAdapter extends BaseAdapter implements Filterable {

    private Context myLayout;
    private ArrayList<Hero> heroes;
    private ArrayList<Hero> filterHeroes;
    MyFilter filter;

    public GridAdapter(Context context , ArrayList<Hero> heroes ) {
        this.myLayout = context;
        this.heroes = heroes;
        this.filterHeroes = heroes;
    }

    @Override
    public Filter getFilter() {
        if (filter == null) {
            filter = new MyFilter();
        }
        return filter;
    }

    @Override
    public int getCount() {
        return heroes.size();
    }

    @Override
    public Object getItem(int position) {
        return heroes.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup 
                         parent) {

        LayoutInflater inflater = LayoutInflater.from(myLayout);
        if (convertView == null) {
            convertView = inflater.inflate(R.layout.grid_items , parent , 
                                           false);
        }
        TextView textView = (TextView) convertView.findViewById(R.id.txt);
        ImageView imageView = (ImageView) convertView.findViewById(R.id.btn);
        textView.setText(heroes.get(position).getTextView());
        imageView.setImageResource(heroes.get(position).getButton());
        convertView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
            }
        });
        convertView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent toAtt = new Intent(Heroes.this,HeroAttributes.class);
                toAtt.putExtra("item",heroes.get(position));
                startActivity(toAtt);
            }
        });
        return convertView;
    }

    class MyFilter extends Filter {

        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            FilterResults results = new FilterResults();
            if (constraint != null && constraint.length() > 0) {
                constraint = constraint.toString().toUpperCase();
                ArrayList<Hero> heroes2 = new ArrayList<>();
                for (int i=0 ; i<filterHeroes.size() ; i++){

    if(filterHeroes.get(i).getTextView().toUpperCase().contains(constraint)){
                        heroes2.add(filterHeroes.get(i));
                    }
                }
                results.count = heroes2.size();
                results.values = heroes2;
            }
            else {
                results.count = filterHeroes.size();
                results.values = filterHeroes;
            }
            return results;
        }

        @Override
        protected void publishResults(CharSequence constraint, FilterResults 
                                        results) {
            heroes = (ArrayList<Hero>) results.values;
            notifyDataSetChanged();
        }
    }
}

Answer 1

您的其中一张图像可能具有高分辨率。使用 Picasso 或 Glide 来解决这个问题，而不是直接使用图像，它们非常擅长缩放图像和调整图像大小。

毕加索:https://square.github.io/picasso/

滑翔:https://github.com/bumptech/glide

毕加索的例子是

Picasso.get().load(heroes.get(position).getButton()).into(imageView);

Glide的例子是

Glide.with(context).load(heroes.get(position).getButton()).into(imageView);

直接imageView.setImageResource(heroes.get(position).getButton());

希望对你有帮助!