Question

当我向上和向下滚动时，我的列表视图正在更新，每次都会更新列表项中的图像。我怎样才能克服这个问题？

这是适配器类

public class CustomAdapter extends BaseAdapter {

    ArrayList<String> p_id;
    ArrayList<String> p_name;
    Context context;
    ArrayList<String> imageId;
    ArrayList<String> wash_v;
    ArrayList<String> dry_v;
    ArrayList<String> iron_v;
    Holder holder;
    Typeface tf;
    ProgressDialog dialog;
    Intent i;
    float washItemCount = 0.0f;
    private static LayoutInflater inflater = null;

    Handler handler;
    Runnable myRunnable;

    public CustomAdapter(Context con, ArrayList<String> pid,
            ArrayList<String> pname, ArrayList<String> pimg,
            ArrayList<String> wash, ArrayList<String> dry,
            ArrayList<String> iron) {
        p_id = pid;
        context = con;
        p_name = pname;
        imageId = pimg;
        wash_v = wash;
        dry_v = dry;
        iron_v = iron;
        inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    }

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

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

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

    public class Holder {
        TextView tv1, tv2, tv3;
        ImageView img;
        LinearLayout ll1, ll2, ll3;
    }

    @SuppressLint("UseValueOf")
    @Override
    public View getView(final int position, final View convertView,
            ViewGroup parent) {
        holder = new Holder();

        final View rowView;

        rowView = inflater.inflate(R.layout.dynamic, null);
        holder.ll1 = (LinearLayout) rowView.findViewById(R.id.ll1);
        holder.ll2 = (LinearLayout) rowView.findViewById(R.id.ll2);
        holder.ll3 = (LinearLayout) rowView.findViewById(R.id.ll3);
        holder.tv1 = (TextView) rowView.findViewById(R.id.tv1);
        holder.tv2 = (TextView) rowView.findViewById(R.id.tv3);
        holder.tv3 = (TextView) rowView.findViewById(R.id.tv5);
        holder.img = (ImageView) rowView.findViewById(R.id.ivImage);

        final TextView tvVal = (TextView) rowView.findViewById(R.id.tvVal);
        final TextView tvVal1 = (TextView) rowView.findViewById(R.id.tvVal1);
        final TextView tvVal2 = (TextView) rowView.findViewById(R.id.tvVal2);

        holder.tv1.setText(wash_v.get(position));
        holder.tv2.setText(dry_v.get(position));
        holder.tv3.setText(iron_v.get(position));

        holder.ll1.setTag(new Integer(position));
        holder.ll2.setTag(new Integer(position));
        holder.ll3.setTag(new Integer(position));

        i = new Intent("com.example.safewash");
        final String image = imageId.get(position).toString();
        Log.i("Image in String", "" + image);

        holder.ll1.setOnClickListener(new OnClickListener() {

            @SuppressLint("NewApi")
            @Override
            public void onClick(final View v) {
                int count = 0;
                int colorStart = Color.LTGRAY;
                int colorEnd = 0;

                ValueAnimator animator = ObjectAnimator.ofInt(v,"backgroundColor", colorStart, colorEnd);
                animator.setDuration(800);
                animator.setEvaluator(new ArgbEvaluator());
                animator.setRepeatCount(0);
                animator.start();

                String washItem = wash_v.get(position);
                int washItems = Integer.parseInt(washItem);

                if (washItems != 0) {

                    washItemCount = Float.parseFloat(washItem);
                    i.putExtra("washItemCount", washItemCount);
                    context.sendBroadcast(i);
                    tvVal.setVisibility(View.VISIBLE);

                    count = Integer.parseInt(tvVal.getText().toString());
                    int countVal = ++count;
                    tvVal.setText("" + countVal);

                }

            }

        });
        holder.ll2.setOnClickListener(new OnClickListener() {

            @SuppressLint("NewApi")
            @Override
            public void onClick(final View v) {
                int count = 0;
                String washItem = dry_v.get(position);
                int colorStart = Color.LTGRAY;
                int colorEnd = 0;

                ValueAnimator animator = ObjectAnimator.ofInt(v,
                        "backgroundColor", colorStart, colorEnd);
                animator.setDuration(800);
                animator.setEvaluator(new ArgbEvaluator());
                animator.setRepeatCount(0);
                animator.start();
                washItemCount = Float.parseFloat(washItem);
                int washItems = Integer.parseInt(washItem);
                if (washItems != 0) {

                    washItemCount = Float.parseFloat(washItem);
                    i.putExtra("washItemCount", washItemCount);
                    context.sendBroadcast(i);
                    tvVal1.setVisibility(View.VISIBLE);
                    count = Integer.parseInt(tvVal1.getText().toString());
                    int countVal = ++count;
                    tvVal1.setText("" + countVal);
                }

            }

        });

        holder.ll3.setOnClickListener(new OnClickListener() {

            @SuppressLint("NewApi")
            @Override
            public void onClick(final View v) {

                int count = 0;

                int colorStart = Color.LTGRAY;
                int colorEnd = 0;

                ValueAnimator animator = ObjectAnimator.ofInt(v,
                        "backgroundColor", colorStart, colorEnd);
                animator.setDuration(800);
                animator.setEvaluator(new ArgbEvaluator());
                animator.setRepeatCount(0);
                animator.start();
                String washItem = iron_v.get(position);
                washItemCount = Float.parseFloat(washItem);
                int washItems = Integer.parseInt(washItem);
                if (washItems != 0) {

                    washItemCount = Float.parseFloat(washItem);
                    i.putExtra("washItemCount", washItemCount);
                    context.sendBroadcast(i);

                    tvVal2.setVisibility(View.VISIBLE);
                    count = Integer.parseInt(tvVal2.getText().toString());
                    int countVal = ++count;
                    tvVal2.setText("" + countVal);

                }
            }
        });

        ImageDownloadTask imageDownloadTask = new ImageDownloadTask();
        imageDownloadTask.execute(image);

        return rowView;
    }

    public class ImageDownloadTask extends AsyncTask<String, Void, Bitmap> {

        @Override
        protected Bitmap doInBackground(String... urls) {
            Bitmap map = null;
            for (String url : urls) {
                map = downloadImage(url);

                Log.i("BitMap in DoinBackGround::", "" + map);
            }
            return map;
        }

        @SuppressWarnings("deprecation")
        @Override
        protected void onPostExecute(Bitmap result) {

            BitmapDrawable ob = new BitmapDrawable(context.getResources(),
                    result);

            holder.img.setBackgroundDrawable(ob);
            super.onPostExecute(result);
        }

    }

    public Bitmap downloadImage(String url) {
        Bitmap bitmap = null;
        InputStream stream = null;
        BitmapFactory.Options bmOptions = new BitmapFactory.Options();
        bmOptions.inSampleSize = 1;

        try {
            stream = getHttpConnection(url);
            bitmap = BitmapFactory.decodeStream(stream, null, bmOptions);

            stream.close();
        } catch (IOException e1) {
            e1.printStackTrace();
        }
        return bitmap;
    }

    private InputStream getHttpConnection(String urlString) throws IOException {
        InputStream stream = null;
        URL url = new URL(urlString);
        URLConnection connection = url.openConnection();

        try {
            HttpURLConnection httpConnection = (HttpURLConnection) connection;
            httpConnection.setRequestMethod("GET");
            httpConnection.connect();

            if (httpConnection.getResponseCode() == HttpURLConnection.HTTP_OK) {
                stream = httpConnection.getInputStream();
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return stream;
    }

}

Answer 1

错误的持有人模式

试试这段代码：

@Override
public View getView(final int position, View convertView, ViewGroup parent) {
    ViewHolder holder;
    if(convertView == null){
        convertView = mInflater.inflate(R.layout...., null);
        holder = new ViewHolder();

        holder.img = (ImageView) convertView.findViewById(R.id....);

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

    // set row code
}

你可以使用图片加载库。（快速和有用......）

如果你有imageurl，你可以替换为AUIL。（而不是ImageDownloadTask）

Android-Universal-Image-Loader：https://github.com/nostra13/Android-Universal-Image-Loader

示例：

ImageLoader.getInstance().displayImage(imageId.get(position).toString(), holder.img, YOUOPTION);

在Android中向上和向下滚动时，我的列表视图是更新？

1 个答案: