Android ArrayList添加项。什么'；我的代码怎么了？

将元素添加到ArrayList时出错。我在

mArrayList.add上出错（oneToolkit）在我的其他活动中，相同的方法工作正常。当我评论
mArrayList.add（oneToolkit）时一切正常。愚弄是我的异步任务代码和在其中调用的方法

private void getToolkits(){     
    JSONObject jsonObject = JSONParser.getJsonObject(URL);
    Log.d(Constants.TAG,"jsonObject: "+jsonObject.toString());
    try {
        JSONArray AllResults = jsonObject.getJSONArray("AppTrainee");
        //Log.d(Constants.TAG,"External Training: "+ AllResults.toString() + " Length: "+ AllResults.length());
        JSONObject newObject = AllResults.getJSONObject(0);
        JSONArray newArray = newObject.getJSONArray("Training Toolkits");
        Log.d(Constants.TAG, "Lenght: "+newArray.length());
        for(int i=0;i<newArray.length();i++){
                JSONObject oneResult = newArray.getJSONObject(i);
                Log.d(Constants.TAG,"Name "+i+" : "+oneResult.getString("ToolkitName"));
                Toolkit oneToolkit = new Toolkit();
                oneToolkit.setToolkitID(Integer.parseInt(oneResult.getString("ToolkitID")));
                oneToolkit.setToolkitName(oneResult.getString("ToolkitName"));
                oneToolkit.setDisplayOrder(Integer.parseInt(oneResult.getString("DisplayOrder")));
                oneToolkit.setButtonImage(oneResult.getString("Tk_ButtonImage"));
                mArrayList.add(oneToolkit);

        }
        Log.d(Constants.TAG, "Done");
    } catch (JSONException e) {
        e.printStackTrace();
    }

}

private void showToolkits(){
    //mAdapter = new ToolkitsAdapter(getApplicationContext(), mArrayList);
    //mGridView.setAdapter(mAdapter);
}

private class GetDataTask extends AsyncTask<String, Void, Void> {
    private final ProgressDialog dialog = new ProgressDialog(ToolkitsActivity.this);

    // can use UI thread here
    protected void onPreExecute() {
        this.dialog.setMessage("Loading...");
        this.dialog.setCancelable(false);
        this.dialog.show();
    }

    // automatically done on worker thread (separate from UI thread)
    protected Void doInBackground(final String... args) {
        getToolkits();
        return null;
    }

    // can use UI thread here
    protected void onPostExecute(final Void unused) {
        if (this.dialog.isShowing()) {
            this.dialog.dismiss();
            showToolkits();
        }
    }
}

private void getToolkits（）{
JSONObject JSONObject=JSONParser.getJsonObject（URL）；
d（Constants.TAG，“jsonObject:+jsonObject.toString（））；
试一试{
JSONArray AllResults=jsonObject.getJSONArray（“AppTraineer”）；
//Log.d（Constants.TAG，“外部培训：+AllResults.toString（）+”长度：+AllResults.Length（））；
JSONObject newObject=AllResults.getJSONObject（0）；
JSONArray newArray=newObject.getJSONArray（“培训工具包”）；
d（Constants.TAG，“Lenght:+newArray.length（））；
对于（int i=0；i这是该错误的原因

Caused by: java.lang.NullPointerException 03-07 22:25:27.788: 

创建此
mArrayList的对象时可能缺少

调试您的代码，我想您发现了错误。
您的婚姻列表为空。请尝试初始化它

List<Toolkit> mArrayList= new ArrayList<Toolkit>();

List mArrayList=new ArrayList（）；
u Marraylist中有NullPointerException发布AsyncTask的完整代码以获取更多信息help@AhmedNawaz不客气。如果这对你有帮助，请接受答案并投赞成票。谢谢
List<Toolkit> mArrayList= new ArrayList<Toolkit>();