使用ProgressDialog直到GridView从webservice加载

Question

我从Web服务中获取GridView的图像和文本,因此需要一些时间来显示GridView.我想显示一个ProgressDialog,直到Grid完全加载.我到现在所做的如下:

public class PCGridMain extends Activity
{
    WebService web = new WebService();
    private GridView gridView;
    ProgressDialog dialog;
    Bitmap icon;


    int i, total;
    URL url= null;
    List<GridItem> list;

    @Override
    public void onCreate(Bundle grid)
    {
        super.onCreate(grid);
        dialog = ProgressDialog.show(PCGridMain.this, "Loading...", "Loading App, Please wait.", true);
        DialogWork dWork = new DialogWork();
        dWork.execute();

        setContentView(R.layout.main);
        gridView = (GridView)findViewById(R.id.gridView1);

        web.WebService1();       
        total = web.totalService;        



        list = new ArrayList<GridItem>();

        for(i=0; i<total; i++)
            {
                    Log.v("Try Block", "See what we get:-");
                    try 
                    {
                        Log.v("GridMain", "try url"  + Integer.toString(i));
                        url = new URL(web.arr[i][2]);
                    }
                    catch (MalformedURLException e)
                    {   
                        Log.v("GridMain", "catch MalformedURLException" + Integer.toString(i));
                        e.printStackTrace();
                    }


                    try
                    {
                        Log.v("GridMain", "try BitmapFactory"  + Integer.toString(i));
                        icon = BitmapFactory.decodeStream(url.openConnection().getInputStream());
                    } 
                    catch (IOException e)
                    {   
                        Log.v("GridMain", "catch IOException"  + Integer.toString(i));
                        e.printStackTrace();
                    }

                    list.add(new GridItem(icon, web.arr[i][1]));                    // Adding Icon & LAbel              

            }

        gridView.setAdapter(new GridAdapter(this, list));
        gridView.setOnItemClickListener(Itemlistener);
    }



    private OnItemClickListener Itemlistener = new OnItemClickListener()
    {
        @Override
        public void onItemClick(AdapterView<?> arg0, View view, int position, long id)
        {
            ViewHolder holder = (ViewHolder)view.getTag();

            if(holder == null)
            {
                return;
            }
            Toast.makeText(PCGridMain.this, holder.label.getText(), Toast.LENGTH_SHORT).show();
                                                                                Log.v("GridMain", "Intent Creation");
            Intent intent = new Intent(view.getContext(), ShowService.class);   Log.v("GridMain", "Intent Created");
            intent.putExtra("ServiceId", web.arr[position][0]);                 Log.v("GridMain", "ValueAdded Sid");
            intent.putExtra("SName", holder.label.getText());                   Log.v("GridMain", "ValueAdded SName");

            startActivity(intent);          

        }
    };

    class DialogWork extends AsyncTask<URL, Integer, Long>
    {       
        protected Long doInBackground(URL... params) 
        {
            try
            {

            }
            catch (Exception e)
            {
                e.printStackTrace();
            }
            return null;
        }

        protected void onProgressUpdate(Integer... progress)
        {

        }

        protected void onPostExecute(Long result)
        {
            try
            {
                //setContentView(R.layout.main);
                //gridView.setAdapter(new GridAdapter(PCGridMain.this, list));              
                dialog.dismiss();                   
            }
            catch (Exception e)
            {
                e.printStackTrace();
                dialog.dismiss();
            }
        }

    }

请告诉我,必须在什么位置放置什么代码,每当我做一些更改时,它都会显示无效或App因某些问题而关闭.

谢谢,

HAPS.

Answer 1

尝试将所有渲染部件从服务器放入doInBackground()并在onPostExecute()中设置适配器.甚至在onPreExecute()中启动progressdialog并在onPostExecute()上关闭它,但不在onCreate()中关闭它.我认为它会解决你的问题....