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我是android新手，所以请耐心等待，我正在创建此代码来绘制图像的gridview，并且我正在使用asynctask，但是我的问题是asynctask正在运行，因此绑定图像变得迟到并且图像未显示，当我调试它时显示它是因为我延迟它所以我知道问题但我希望有人为我修复语法，非常感谢。

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.Drawable;
import android.os.AsyncTask;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.ListAdapter;

public class ImagesAdapter extends BaseAdapter implements ListAdapter {
private Context mContext;
ImageView currentImageView;
Bitmap bmImg;

// Constructor
public ImagesAdapter(Context c) {
    super();
    mContext = c;
    GridViewConfig.addImageUrls();
}

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

@Override
public Object getItem(int position) {
    return GridViewConfig.getResim_list().get(position);

}

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

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

    ImageView imageView;

    if (convertView == null)

    {

        imageView = new ImageView(mContext);

        imageView.setLayoutParams(new GridView.LayoutParams(100, 100));

        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);

        imageView.setPadding(5, 5, 5, 5);

    } else {

        imageView = (ImageView) convertView;

    }
    downloadFile(GridViewConfig.getResim_list().get(position));

    imageView.setImageBitmap(bmImg);

    // imageView.setImageDrawable(LoadImageFromURL(GridViewConfig
    // .getResim_list().get(position)));

    return imageView;

}

void downloadFile(String fileUrl) {

    AsyncTask<String, Object, String> task = new AsyncTask<String, Object, String>() {

        @Override
        protected String doInBackground(String... params) {
            URL myFileUrl = null;
            try {
                myFileUrl = new URL(params[0]);
            } catch (MalformedURLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            try {
                HttpURLConnection conn = (HttpURLConnection) myFileUrl
                        .openConnection();
                conn.setDoInput(true);
                conn.connect();
                InputStream is = conn.getInputStream();

                bmImg = BitmapFactory.decodeStream(is);

            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            return null;
        }

        protected void onPostExecute(String unused) {
        /*  if (currentImageView == null) {
                currentImageView = new ImageView(mContext);
            }
            currentImageView.setImageBitmap(bmImg); */
        }
    };
    task.execute(fileUrl);

}

gridviewconfig 类返回所需的图像。

4

1 回答 1

0

看看http://developer.android.com/training/displaying-bitmaps/index.html有一个带有网格的 BitmapFun 示例项目/应用程序和许多有用的东西。我建议你不要重新发明轮子，而是使用谷歌的代码，他们是 Android 的创造者，
我也建议你研究一些 LazyList 实现

于 2013-04-26T13:09:21.813 回答