如何在android中解析json解析中的有限記錄

Question

我想要做的第一件事是將進度對話框添加到我的應用程序列表活動中。活動並不耗費時間（反正不多），但是當從json解析並嵌入到listactivity中解析數據的活動給用戶留下不好的印象時，您不希望UI不響應。 請幫我

Answer 1

使用的AsyncTask顯示進度對話框，在分析數據

private class DownloadingProgressTask extends 
     AsyncTask<String, Void, Boolean> { 

    private ProgressDialog dialog = new ProgressDialog(ShowDescription.this); 

    /** progress dialog to show user that the backup is processing. */ 

    /** application context. */ 

    protected void onPreExecute() { 
     this.dialog.setMessage("Please wait"); 
     this.dialog.show(); 

    } 

    protected Boolean doInBackground(final String... args) { 
     try { 
      downloadFile(b.getString("URL")); 
      return true; 
     } catch (Exception e) { 
      Log.e("tag", "error", e); 
      return false; 
     } 
    } 

    @Override 
    protected void onPostExecute(final Boolean success) { 

     if (dialog.isShowing()) { 
     dialog.dismiss(); 
     } 

     if (success) { 
      Toast.makeText(ShowDescription.this, 
        "File successfully downloaded", Toast.LENGTH_LONG) 
        .show(); 
      //imgDownload.setVisibility(8); 
     } else { 
      Toast.makeText(ShowDescription.this, "Error", Toast.LENGTH_LONG) 
        .show(); 
     } 
    } 

}