替换图像时动态刷新gridview。 notifyDataSetChanged（）不起作用

Question

我有GridView从SD卡（如果有）加载图像，否则会加载一些默认图像。加载图像后，用户可以选择任何图像单元并拍摄新照片。当GridView中加载默认图片并且用户拍照时，GridView会更新并显示图片 - 但如果用户再次点击该单元格并拍摄新照片，则GridView不会更新。只有当我杀死应用程序并重新启动它时，才会显示新图片。

我尝试了notifyDataSetChanged()但是在刷新图片时它不起作用。

以下是代码：

public class Fragment1 extends SherlockFragment {
...
private Integer[] mThumbIds = { R.drawable.fr, R.drawable.siderelaxed3,
        R.drawable.br, R.drawable.fdbth, R.drawable.bdb, R.drawable.bls,
        R.drawable.fls, R.drawable.mm };


private ImageAdapter imageAdapter;
ArrayList<String> f = new ArrayList<String>();// list of file paths
File[] listFile;
ImageLoader imageLoader;    
Context context;
boolean needToRefresh = true;


/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    context = getActivity();
    date = util.getCurrentDate();
    Bundle bundle = this.getArguments();
    date = bundle.getString(MyCommons.SELECTED_DATE);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View mainView = inflater.inflate(R.layout.picturerecord, container,
            false);

    getFromSdcard();
    Grid = (GridView) mainView
            .findViewById(R.id.pictureRecordGrid);
    imageAdapter = new ImageAdapter();
    Grid.setAdapter(imageAdapter);
    imageLoader = new ImageLoader(context, 4);

    try {
        ourClass = Class
                .forName("cameraOpen");
        ourIntent = new Intent(context, ourClass);

    } catch (ClassNotFoundException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }

    poseGrid.setOnItemClickListener(new OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View v,
                int position, long id) {
            startActivityForResult(ourIntent, CAMERA_REQUEST);
            poseSelected = position;
        }
    });     
    return mainView;

}

public void getFromSdcard() {
    f.clear();
    for (int  i = 0; i < MyCommons.POSES_TO_LOAD.length; i++) {
        String pose = MyCommons.pose_names[i];
        String path = MyCommons.rootPath + File.separator + pose
                + File.separator + date;
        File imgFile = new File(path);
        if (imgFile.exists()) {
            f.add(path);
            Log.d(TAG, "image is present at:" + path);
        } else {
            f.add("loaddefault");
        }
    }
}
public class ImageAdapter extends BaseAdapter {
    private LayoutInflater mInflater;

    public ImageAdapter() {
        mInflater = (LayoutInflater) context.getSystemService(
                Context.LAYOUT_INFLATER_SERVICE);
    }

    public int getCount() {
        return f.size();
    }

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

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

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (needToRefresh == true) {
            convertView = null;
            Log.d(TAG, "NEEDED REFRESH");
            needToRefresh = false;
        }
        if (convertView == null) {
            holder = new ViewHolder();
            convertView = mInflater.inflate(R.layout.picturerecorddata,
                    null);
            holder.imageview = (ImageView) convertView
                    .findViewById(R.id.pictureRecordImage);
            holder.textview = (TextView) convertView.findViewById(R.id.pictureRecordText);

            convertView.setTag(holder);

        } else {
            holder = (ViewHolder) convertView.getTag();             
        }

        if (f.get(position).equals("loaddefault")) {
            DefaultImageLoader defaultImages = new DefaultImageLoader(holder.imageview);
            defaultImages.execute(position);
            } else {
            imageLoader.DisplayImage(f.get(position), holder.imageview, mThumbIds[position], position);
        }

        holder.textview.setText(MyCommons.pose_names[position]);
        return convertView;
    }
}

class ViewHolder {
    ImageView imageview;
    TextView textview;

}


@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == CAMERA_REQUEST) {
        if (resultCode == Activity.RESULT_OK) {
            Bitmap photo = BitmapFactory.decodeByteArray(
                    data.getByteArrayExtra("BitmapImage"), 0,
                    data.getByteArrayExtra("BitmapImage").length);

            ByteArrayOutputStream bytes = new ByteArrayOutputStream();
            photo.compress(Bitmap.CompressFormat.JPEG, 100, bytes);


            File root = new File(MyCommons.rootPath);

            if (!root.exists()) {
                root.mkdirs();
                Log.d(TAG, "Created Progress pics directory.");
            }

            String poseName = MyCommons.pose_names[poseSelected];

            File pose_dir = new File(root + File.separator + poseName);
            if (!pose_dir.exists()) {
                pose_dir.mkdirs();
                Log.d(TAG, "Created" + pose_dir + " pics directory.");
            }
            String tempFileName = root + File.separator + poseName + File.separator + date;
            File tempFile = new File(tempFileName);
            if (tempFile.exists()) {
                Log.d(TAG, "File already exist. deleteing it and will write new file:" + tempFileName);

                tempFile.delete();
            }
            util.saveImage(bytes, pose_dir, date);

            Log.d(TAG, "image saved. Reloading adapter:\n"  + tempFileName);
            f.remove(tempFileName);

            getFromSdcard();                
            f.add(poseSelected, tempFileName);  
                //f.clear();                
            //f.addAll(f);              
            imageAdapter.notifyDataSetChanged();

            Grid.invalidateViews();
            Grid.setAdapter(imageAdapter);                          
        }
    }
}
...

}

Answer 1

你需要用新图片替换列表f中的图像，然后使用f中的项目来调用notify，adapter for diplaying