Question

我正在使用这个Asnc类我的应用程序，但有时我退出应用程序。它崩溃了。 “窗口泄漏错误：在行progDialog.show（）;” - 猜猜ProgressDialog引起了问题，因为它仍然引用了活动（上下文），但我不能使用getApplicationContext（），如果我使用getApplicationContext（），那么ProgressDialog将不起作用。我该如何解决这个问题？

protected void executeSLPWebserviceTask(double latitude, double longitude,
        String progressStr) {
    WebserviceTask task = new WebserviceTask(this, progressStr);
    task.execute(latitude, longitude);
}



class WebserviceTask extends AsyncTask<Double, Void, Float> implements OnDismissListener{

    Context context;
    ProgressDialog progDialog;
    String progressString;

    public WebserviceTask(Context context, String progressStr) {

        this.context = context;
        this.progressString = progressStr;
        initProgDialog();
    }

    void initProgDialog(){
        if(!isCancelled()){
            try {
                progDialog = new ProgressDialog(context);
                progDialog.setCanceledOnTouchOutside(false);
                progDialog.setButton(DialogInterface.BUTTON_NEGATIVE, getString(R.string.btn_cancel),new DialogInterface.OnClickListener() {
                    public void onClick(final DialogInterface dialog, final int id) {
                        progDialog.dismiss();
                    }
                });
                progDialog.setMessage(progressString);
                progDialog.setOnDismissListener(this);
                progDialog.show();
            } catch (Exception e) {
                Log.e("Web&RemoteServiceActivity", "Failed to add window for web service task");
            }
        }
    }

    @Override
    protected void onPreExecute() {
        addTask(this);
        super.onPreExecute();
    }

    protected Float doInBackground(Double... latLong) {
        Float slpFloat = 0f;
        if(!isCancelled()){
            if(internetServiceBound)
            {
                try {
                    slpFloat = internetSLPService.getSLPFromInternet(latLong[0].floatValue(),latLong[1].floatValue());
                } catch (RemoteException e) {
                    Log.e("Webservice task", "Failed to get slp - Remote exception");
                    this.cancel(true);
                }
                catch (NullPointerException e) {
                    Log.e("Webservice task", "Failed to get slp - Null pointer exception");
                    this.cancel(true);
                }
            }
        }
        return slpFloat;
    }

    protected void onPostExecute(Float slpFloat) {
        if (!isCancelled()) {
            if(slpFloat >= 300 && slpFloat<=1100){
                //seaLevelPressure = slpFloat;  
                setReferenceSeaLevelPressure(slpFloat);
                updateSeaLevelPressureFromWeb(slpFloat);
                Toast toast = Toast.makeText(getApplicationContext(), getString(R.string.msg_slp_updated_from_internet) + " : " + slpFloat, Toast.LENGTH_LONG);
                toast.show();
                addToastJob(toast);
                progDialog.dismiss();
                //lastCalibratedTime = System.currentTimeMillis();

            }else if(slpFloat==0){
                //If SLP value returned is 0, notify slp fetch fail and cancel progress dialog
                Toast toast = Toast.makeText(getApplicationContext(),getString(R.string.msg_slp_fetch_fail), Toast.LENGTH_SHORT);
                toast.show();
                addToastJob(toast);
                progDialog.dismiss();
            }else{
                //Notify invalid SLP and cancel progress dialog
                Toast toast = Toast.makeText(getApplicationContext(),getString(R.string.msg_internet_slp_invalid), Toast.LENGTH_SHORT);
                toast.show();
                addToastJob(toast);
                progDialog.dismiss();
            }
        }
        this.cancel(true);
    }

    public void onDismiss(DialogInterface dialog) {
        this.cancel(true);
    }

    @Override
    protected void onCancelled() {
        if(progDialog != null){
            if(progDialog.isShowing())
                progDialog.dismiss();

        }
        super.onCancelled();
    }

}

Answer 1

通过覆盖活动中的onCreateDialog（int id）来创建progressDialog。在onPreExecute（）方法的任务中使用showDialog（PROGRESS_DIALOG_ID）;并在onPostExecute（）方法中使用dismissDialog（PROGRESS_DIALOG_ID）;

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1 个答案: