Question

我正在开发一个项目，列表视图应该自动更新数据库更改，我正在研究它很长一段时间并找到一个使用ViewHolder模式的解决方案，我尝试了这种方式，它真的很有效！但现在我尝试了许多解决方案再做一次，它不起作用!!请帮助我或告诉我是否有使用此模式的提示。真谢谢！

public class DownloadItem_ViewHolder {

private boolean hasInited = false;
public DownloadItem_ViewHolder() {

}
public DownloadItem_ViewHolder(View convertView) {
    if (convertView != null) {
        App_icon = (ImageView) convertView
                .findViewById(R.id.Download_app_icon);
        App_name = (TextView) convertView
                .findViewById(R.id.Downlaod_app_name);
        Downloaded_percent = (TextView) convertView
                .findViewById(R.id.Downloaded_app_percent);
        Downloaded_progress = (ProgressBar) convertView
                .findViewById(R.id.Downloaded_app_progress);
        Pause_btn = (ImageView) convertView
                .findViewById(R.id.Download_pause_btn);
        Resume_btn = (ImageView) convertView
                .findViewById(R.id.Download_Resume_btn);
        hasInited = true;
    }
}
public void setPorgress(int progress) {
    Downloaded_progress.setProgress(progress);
    // Downloaded_percent.setText(String.valueOf(progress) + "%");
}
public void setData(DownloadManagerItem_Cls dlItem) {
    if (hasInited) {
        // this.App_icon.setBackground(newDownloadManager.getDownloadItemApp(
        // dlItem.getItemID()).getAppIcon());
        // App_name.setText(newDownloadManager.getDownloadItemApp(
        // dlItem.getItemID()).getAppName()
        // + "-->" + dlItem.getItemID());
        this.Downloaded_progress
                .setProgress(dlItem.getDownloadPercentage());
        // this.Downloaded_percent.setText(String.valueOf(dlItem
        // .getDownloadPercentage()) + "%");
        // DownloadStatus downloadItemStatus = dlItem.getDownloadStatus();
        // // PAUSE
        // if (downloadItemStatus.equals(DownloadStatus.Pause)) {
        // // Resume
        // Resume_btn.setVisibility(View.VISIBLE);
        // // Pause
        // Pause_btn.setVisibility(View.GONE);
        // } else if (downloadItemStatus.equals(DownloadStatus.Downloading))
        // {// Resume
        // Resume_btn.setVisibility(View.GONE);
        // // Pause
        // Pause_btn.setVisibility(View.VISIBLE);
        // } else if (downloadItemStatus.equals(DownloadStatus.Complete)) {
        // // Resume
        // Resume_btn.setVisibility(View.GONE);
        // // Pause
        // Pause_btn.setVisibility(View.GONE);
        // // Install or Run
        // }
    }
}
ImageView App_icon;
public TextView App_name;
ProgressBar Downloaded_progress;
TextView Downloaded_percent;
public ImageView Resume_btn;
public ImageView Pause_btn;

}

public class DownloadItemAdpater extends ArrayAdapter<DownloadManagerItem_Cls> {

int _rowResourceID;
public DownloadItemAdpater(Context context, int rowResourceID,
        List<DownloadManagerItem_Cls> DownloadedItems) {
    super(context, rowResourceID, DownloadedItems);
    _rowResourceID = rowResourceID;
}

@Override
public View getView(final int position, View convertView, ViewGroup parent) {
    // final int AppID = DownloadManager.DownloadedList.get(position).ApkID;
    if (convertView == null) {
        LayoutInflater vi = (LayoutInflater) getContext().getSystemService(
                Context.LAYOUT_INFLATER_SERVICE);
        convertView = vi.inflate(R.layout.download_history_item, null);
        // store the holder with the view.
        // convertView.setTag(1, viewHolder);

    }
    convertView.setTag(getItem(position).getItemID());
    DownloadItem_ViewHolder viewHolder = new DownloadItem_ViewHolder(
            convertView);

    viewHolder.setData(getItem(position));
    viewHolder.App_name.setText(String.valueOf(getItem(position)
            .getItemID()));
    // set data
    // viewHolder.Pause_btn.setOnClickListener(new DownloadBtnListener(
    // position, viewHolder));
    // viewHolder.Resume_btn.setOnClickListener(new DownloadBtnListener(
    // position, viewHolder));
    return convertView;
}

public class DownloadManager_Act extends ListActivity {
DownloadItemAdpater dlAdapter;
ArrayList<DownloadManagerItem_Cls> listHistory;
// @Override
// protected void onDestroy() {
// unregisterReceiver(mReceiver);
// super.onDestroy();
// }
MyReceiver mReceiver;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.dl_manager);
    listHistory = CP_Connector.GDM_QueueTable_Connector.getDownloadList();
    dlAdapter = new DownloadItemAdpater(getApplicationContext(),
            R.layout.download_history_item, listHistory);
    setListAdapter(dlAdapter);
    mReceiver = new MyReceiver();
    IntentFilter filter = new IntentFilter();
    filter.addAction("com.glx.appscenter.dlmanager");
    registerReceiver(mReceiver, filter);
}

public class MyReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        if (intent != null
                && intent.getAction()
                        .equals("com.glx.appscenter.dlmanager")) {
            try {
                int dlItemID = Integer.valueOf(intent
                        .getStringExtra("itemID"));
                if (dlItemID >= 0) {

                    DownloadManagerItem_Cls dlTempItem = CP_Connector.GDM_QueueTable_Connector
                            .getDownloadItemByID(dlItemID);
                    View v = getListView().findViewWithTag(
                            dlTempItem.getItemID());
                    TextView tv = (TextView) v
                            .findViewById(R.id.Downlaod_app_name);
                    Utility.appUtility.ShowToast(String.valueOf(tv
                            .getText() + ":" + dlItemID));
                    DownloadItem_ViewHolder viewHolder = new DownloadItem_ViewHolder(
                            v);
                    viewHolder.setPorgress(dlTempItem
                            .getDownloadPercentage());
                    dlAdapter.notifyDataSetChanged();
                }
            } catch (Exception e) {
            }

        }
    }
}

}

Answer 1

如果要设置适配器，请遵循此代码。

adapter=new AuctionListAdapter(getActivity(), listAuctionBeans,progressBar,1);
setListAdapter(adapter);

如果你想用新的数据更改刷新列表，请按照

进行操作

adapter.addData(getActivity(), listAuctionBeans);
adapter.notifyDataSetChanged();

和适配器就是你的d1Adapter。

使用viewHolder刷新列表视图数据

1 个答案: