Question

我正在开发一个Android项目，其中包含向用户显示的项目列表及其图像。现在的问题是因为我必须做的修改来设置列表，我不知道如何更改代码以包含用户点击的对象的id。我不喜欢这个位置，而是从服务器收到的id。你能帮忙的话，我会很高兴。非常感谢。： - ）

请注意，相关代码在下面的第一个类中更多，如果需要修改，我只是放了LazyAdapter。非常感谢。

GroupCanvasActivity.java：

public class GroupCanvasActivity extends Activity {

    private static volatile Long groupAccountid = (long) 0;

    List<RestCanvas> restCanvasList = new ArrayList<>();

    private CanvasServiceImpl canvasService = new CanvasServiceImpl();

    LazyAdapter lazyAdapter;
    ListView listView;

    static final String mcanvasid = "canvasid";
    static final String mcanvastitle = "canvastitle";
    static final String mcanvasname = "mcanvasname";
    static final String mcanvasimage = "mcanvasimage";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.canvaslayout);


        Bundle extras = getIntent().getExtras();
        if (extras != null) {
            groupAccountid = extras.getLong("groupid");
        }

        restCanvasList = this.canvasService.getGroupCanvasForGroupAccount(groupAccountid);

        ArrayList<HashMap<String, String>> canvaslist = new ArrayList<HashMap<String, String>>();
        for (RestCanvas restCanvas : restCanvasList) {
            HashMap<String, String> canvasDisplay = new HashMap<>();
// The below mcanvasid is what I would like to get when clicked
            canvasDisplay.put("mcanvasid", String.valueOf(restCanvas.getMcanvasid()));
            canvasDisplay.put("mcanvastitle", restCanvas.getMcanvastitle());
            canvasDisplay.put("mcanvasname", restCanvas.getMcanvasname());
            canvasDisplay.put("mcanvasimage", restCanvas.getMcanvasimage());
            canvaslist.add(canvasDisplay);
        }

        listView = (ListView) findViewById(R.id.canlist);

        lazyAdapter = new LazyAdapter(this, canvaslist);
        listView.setAdapter(lazyAdapter);

        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                                    int position, long id) {
// In the for loop above, you can see the mcanvasid, which I would like to use here. 

            }
        });


    }
}

LazyAdapter.java：

  public class LazyAdapter extends BaseAdapter {

        private Activity activity;
        private ArrayList<HashMap<String, String>> data;
        private static LayoutInflater inflater=null;


        public LazyAdapter(Activity a, ArrayList<HashMap<String, String>> d) {
            activity = a;
            data=d;
            inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        }

        public int getCount() {
            return data.size();
        }

        public Object getItem(int position) {
            return position;
        }

        public long getItemId(int position) {
            return position;
        }

        public View getView(int position, View convertView, ViewGroup parent) {
            View vi=convertView;
            if(convertView==null)
                vi = inflater.inflate(R.layout.activity_group_canvas, null);

            TextView canvasName = (TextView)vi.findViewById(R.id.canvasname); // id
            TextView canvasTitle = (TextView)vi.findViewById(R.id.canvastitle); // title
            ImageView canvasImage=(ImageView)vi.findViewById(R.id.canvasimage); // image

            HashMap<String, String> canvasList = new HashMap<String, String>();
            canvasList = data.get(position);


            canvasName.setText(canvasList.get(GroupCanvasActivity.mcanvasid));
            canvasTitle.setText(canvasList.get(GroupCanvasActivity.mcanvasname));
            canvasImage.setImageBitmap(convertByteArrayToBitmap(canvasList.get(GroupCanvasActivity.mcanvasimage)));
            return vi;
        }


        private Bitmap convertByteArrayToBitmap(String string){
            byte [] encodeByte= Base64.decode(string, Base64.DEFAULT);
            return BitmapFactory.decodeByteArray(encodeByte, 0, encodeByte.length);
        }

    }

任何帮助都会很好。谢谢。： - ）

Answer 1

这样做：

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                                    int position, long id) {
                String mcanvasid  = restCanvasList.get(position).get("mcanvasid"); // Here you get the mcanvasid

            }
        });

Answer 2

试试这个。在适配器中：

    public Object getItem(int position) {
        return d.get(position);
    }

，在您的活动中：

    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                                int position, long id) {
            String output = (HashMap<String, String>)(parent.getAdapter.getItem(position)).get("mcanvasid");
            //do what you want with output
        }
    });

Android：设置并获取包含文字和图片的列表的点击项ID。

2 个答案: