Question

我正在使用AssetManager从资源/图像加载图像，加载过程顺利，因为我可以看到所有图像都已加载到库中，但画廊只显示框架而不是图片，我尝试了不同的mime类型png，jpg和bmp并没有成功。

这是我从assets / image

加载图像的方法

private List<String> getImage() throws IOException
  {
    AssetManager assetManager = getAssets();
    String[] files = assetManager.list("image");   
    List<String> it=Arrays.asList(files);
    return it; 

    }

这是我的imageadapter

public class ImageAdapter extends BaseAdapter 
      {
        /*声明变量*/
        private Context mContext;
        private List<String> lis;

        /*ImageAdapter的构造符*/
        public ImageAdapter(Context c,List<String> li) 
        {
          mContext = c;
          lis=li;

        }

        /*几定要重写的方法getCount,传回图片数目*/
        public int getCount() 
        {
          return lis.size();
        }

        /*一定要重写的方法getItem,传回position*/
        public Object getItem(int position) 
        {
          return position;
        }

        /*一定要重写的方法getItemId,传并position*/
        public long getItemId(int position) 
        {
          return position;
        }

        /*几定要重写的方法getView,传并几View对象*/
        public View getView(int position, View convertView, 
                              ViewGroup parent) 
        {
          /*产生ImageView对象*/
          ImageView i = new ImageView(mContext);
          /*设定图片给imageView对象*/
          Bitmap bm = BitmapFactory.decodeFile(lis.
                                get(position).toString());
          i.setImageBitmap(bm);
          /*重新设定图片的宽高*/
          i.setScaleType(ImageView.ScaleType.FIT_XY);
          /*重新设定Layout的宽高*/
          i.setLayoutParams(new Gallery.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));

          return i;
        }     
      } 
    }

这就是我发布图库的方式

 Gallery g = (Gallery) findViewById(R.id.mygallery);

            /*新增几ImageAdapter并设定给Gallery对象*/
            try {
                g.setAdapter(new ImageAdapter(this,getImage()));
            } catch (IOException e) {
                Log.e("tag", "取得图片失败");
            }

logcat打印没有错误

Answer 1

请确保'lis'包含完整路径名，否则您可能必须在文件名前添加路径。完成后尝试以下更改

    public View getView(int position, View convertView, ViewGroup parent) 
    {
      if (convertView == null) { 
          ImageView i = new ImageView(mContext);
       }
      else { 
          ImageView i = (ImageView) convertView;
       }

      i.setScaleType(ImageView.ScaleType.FIT_XY);
      i.setLayoutParams(new Gallery.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));

      Bitmap bm = BitmapFactory.decodeFile(lis.
                            get(position).toString());
      i.setImageBitmap(bm);
      return i;
    }

Answer 2

尝试这样做......

private List<String> getImage() throws IOException {
        AssetManager assetManager = getAssets();
        String[] files = assetManager.list("image");
        List<String> list = new ArrayList<String>();
        for (String it : files) {
            list.add("image" + File.separator + it);
        }
        return list;

    }





public class ImageAdapter extends BaseAdapter {
        private Context mContext;
        private List<String> list;

        public ImageAdapter(Context c, List<String> list) {
            mContext = c;
            this.list = list;
        }

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

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

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

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ImageView iv = null;
            try {

                if (convertView == null) {
                    convertView = new ImageView(mContext);
                    ((ImageView) convertView).setAdjustViewBounds(true);
                    convertView.setLayoutParams(new Gallery.LayoutParams(
                            LayoutParams.WRAP_CONTENT,
                            LayoutParams.WRAP_CONTENT));
                    convertView.setBackgroundResource(R.drawable.picture_frame);
                }
                iv = (ImageView) convertView;

                InputStream is = getAssets().open(list.get(position));

                Bitmap bm = BitmapFactory.decodeStream(is);

                iv.setImageBitmap(bm);
            } catch (Throwable ex) {
            }
            return iv;
        }
    }

现在进入你的onCreate方法

private Gallery galery;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        galery = (Gallery) findViewById(R.id.gallery);
        try {
            galery.setAdapter(new ImageAdapter(this, getImage()));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

从资源文件夹加载图像时，图库显示空白

2 个答案: