Question

活动A 中有listView和添加button。从listView检索MySQL数据。

[！[http://i.stack.imgur.com/wVmSK.png][1]][1]

点击列表时，会将数据传递给活动B ，如果点击添加button，则会转到活动B 以供用户使用添加数据。我使用mClickedPosition来区分点击list或点击button。

活动A

   ListView listViewUpdate;
    ListAdapter adapter;
    Button add;
    String ID, iD;
    public static final int PROJECT_REQUEST_CODE = 1;
    public static final int CAMERA_REQUEST_CODE = 2;
    int mClickedPosition;
    String ReceiveProject, ReceiveDescription, ReceiveTimeIn, ReceiveTimeOut;
    Integer ReceiveProgress;
    ArrayList<DetailsBean> results = new ArrayList<DetailsBean>();
    String myJSON;
    JSONArray details = null;
    ArrayList<HashMap<String, String>> EditDetails;

     listViewUpdate.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                @Override
                public void onItemClick(AdapterView<?> listView, View view,
                                        int position, long id) {
                    mClickedPosition = position; // listView click
                    HashMap<String, String> clickedItem = EditDetails.get(position);
                    iD = clickedItem.get(Configs.TAG_ID);
                    Intent intent = new Intent(getActivity(), Edit_Details.class);
                    intent.putExtra("iD", iD);
                    intent.putExtra("ID", ID);
                    intent.putExtra("mClickedPosition",mClickedPosition);
                    //Toast.makeText(getActivity(),"This is"+iD+ID,Toast.LENGTH_LONG).show();
                    startActivityForResult(intent, PROJECT_REQUEST_CODE);

                }
            });


          add.setOnClickListener(new View.OnClickListener() {
              @Override
              public void onClick(View v) {
                  mClickedPosition = -1;    // if button clicked
                  Intent intent = new Intent(getActivity(), Edit_Details.class);
                  intent.putExtra("ID", ID);
                  startActivity(intent);
              }

          });

假设用户点击添加button。（mClickedposition == - 1）

活动B

点击保存button后，数据将插入MySQL，因为 mClickedPosition == - 1 之后，我希望新数据返回到活动A并添加A中的新列表，表示活动A现在应该有2个列表。我怎样才能做到这一点？

 save.setOnClickListener(new View.OnClickListener() {     // if save button clicked
            @Override
            public void onClick(View v) {
                Intent returnIntent = new Intent();
                project1 = Project2.getSelectedItem().toString();
                description = Description.getText().toString();
                progress = seekBar.getProgress();
                timeIn = TimeIn.getText().toString();
                timeOut = TimeOut.getText().toString();
                if(mClickedPosition==-1)
                {
                    Add(project1,description,progress,timeIn,timeOut);
                }
                else
                {
                    Update(project1, description, progress, timeIn, timeOut);
                }
                returnIntent.putExtra("project1", project1);
                returnIntent.putExtra("description", description);
                returnIntent.putExtra("progress", progress);
                returnIntent.putExtra("timeIn", timeIn);
                returnIntent.putExtra("timeOut", timeOut);
                setResult(Activity.RESULT_OK, returnIntent);
                finish();

            }
        });

活动A onActivityResult

  @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) { // receive from Activity B and populate ListView A
        if (resultCode == Activity.RESULT_OK) {
            if (requestCode == PROJECT_REQUEST_CODE) {
                ReceiveProject = data.getStringExtra("project1");
                ReceiveDescription = data.getStringExtra("description");
                ReceiveProgress = data.getIntExtra("progress", 0);
                ReceiveTimeIn = data.getStringExtra("timeIn");
                ReceiveTimeOut = data.getStringExtra("timeOut");


                Toast.makeText(getActivity(),ReceiveProject+ReceiveDescription+ReceiveProgress+ReceiveTimeIn+ReceiveTimeOut,Toast.LENGTH_LONG).show();
                if(mClickedPosition==-1)
                { // add list
                    HashMap<String, String> clickedItem = new HashMap<>();
                    clickedItem.put(Configs.TAG_PROJECT, ReceiveProject);
                    clickedItem.put(Configs.TAG_WORKDESCRIPTION, ReceiveDescription);
                    clickedItem.put(Configs.TAG_PERCENTAGE, ReceiveProgress + "");
                    clickedItem.put(Configs.TAG_IN, ReceiveTimeIn);
                    clickedItem.put(Configs.TAG_OUT, ReceiveTimeOut);
                    EditDetails.add(clickedItem);
                    ((BaseAdapter) adapter).notifyDataSetChanged();

                }
                else
                {  // update list
                    HashMap<String, String> clickedItem =EditDetails.get(mClickedPosition);
                    clickedItem.put(Configs.TAG_PROJECT, ReceiveProject);
                    clickedItem.put(Configs.TAG_WORKDESCRIPTION, ReceiveDescription);
                    clickedItem.put(Configs.TAG_PERCENTAGE, ReceiveProgress + "");
                    clickedItem.put(Configs.TAG_IN, ReceiveTimeIn);
                    clickedItem.put(Configs.TAG_OUT, ReceiveTimeOut);
                    ((BaseAdapter) adapter).notifyDataSetChanged();
                }
                //((BaseAdapter) adapter).notifyDataSetChanged();
            }
            }
    }
    }

现在我可以看到活动A中添加了一个新列表。但是当我点击新列表时列表并转到活动B，不传递任何数据。但如果我点击旧的列表，我可以看到传递的数据...

Answer 1

您需要在列表中添加或更新新数据，然后调用notifiDataSetChanged(); 更改活动A的onActivity结果方法中的代码，如下所示 -

                HashMap<String, String> item =        new HashMap<>();
                item.put(Configs.TAG_PROJECT, ReceiveProject);
                item.put(Configs.TAG_WORKDESCRIPTION, ReceiveDescription);
                item.put(Configs.TAG_PERCENTAGE, ReceiveProgress + "");
                item.put(Configs.TAG_IN, ReceiveTimeIn);
                item.put(Configs.TAG_OUT, ReceiveTimeOut);

                if(mClickedPosition==-1)
                { // add list
                    EditDetails.add(item);

                }
                else
                {  // update list
                    EditDetails.remove(mClickedPosition);
                    mEventsList.add(mClickedPosition,item)
                }
                ((BaseAdapter) adapter).notifyDataSetChanged();

将新列表添加到listView

1 个答案: