Question

从Android dev开始，我对ListView的更新有疑问。按照一些教程，我能够做到：

Spinner有4个项目（客户A，客户B，客户C，客户D）;
ListView Checkbox和TextView说每个客户的项目;

每个客户都有自己的项目，我们的想法是更新ListView，以便在Spinner中选择时显示每个客户项目，例如：

Client A - ＆gt;项目1，项目2，项目3，（......），项目7;
Client B - ＆gt;项目8，项目9，（......），项目16。

为此，我使用Base Adapter引用single_row.xml来为每个视图设置布局。

有关客户端的信息是在clientes_array文件中名为strings.xml的数组上设置的。我还有projectsA和projectsB的数组。

strings.xml：

<string-array name="clientes_array"> <item>Cliente A</item> <item>Cliente B</item> <item>Cliente C</item> <item>Cliente D</item> </string-array> <string-array name="projectoA"> <item>Projecto #1</item> <item>Projecto #2</item> <item>Projecto #3</item> <item>Projecto #4</item> <item>Projecto #5</item> <item>Projecto #6</item> <item>Projecto #7</item> </string-array> <string-array name="projectoB"> <item>Projecto #8</item> <item>Projecto #9</item> <item>Projecto #10</item> <item>Projecto #11</item> <item>Projecto #12</item> <item>Projecto #13</item> <item>Projecto #14</item> <item>Projecto #15</item> <item>Projecto #16</item> </string-array>

这是我的Activity代码：

`public class AddProj_Activity扩展了Activity实现 AdapterView.OnItemSelectedListener {

Spinner spinner1;
Button botaoAdd;
ListView listView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.addproj_layout);

    spinner1 = (Spinner) findViewById(R.id.spinner1);
    botaoAdd = (Button) findViewById(R.id.addProj);
    listView = (ListView) findViewById(android.R.id.list);

    listView.setAdapter(new Adaptador(this));

    ArrayAdapter adapter2 = ArrayAdapter.createFromResource(this,
            R.array.clientes_array, R.layout.spinner_item);
    adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinner1.setAdapter(adapter2);

    spinner1.setOnItemSelectedListener(this);

}

@Override
public void onItemSelected(AdapterView<?> parent, View view, int position,
        long id) {
    // TODO Auto-generated method stub

}

@Override
public void onNothingSelected(AdapterView<?> parent) {
    // TODO Auto-generated method stub

}

class SingleRow {
    String projecto;

    public SingleRow(String projecto) {
        // TODO Auto-generated constructor stub
        this.projecto = projecto;
    }

}

class Adaptador extends BaseAdapter {

    ArrayList<SingleRow> listSR;
    Context context;

    public Adaptador(Context c) {
        // TODO Auto-generated constructor stub
        context = c;
        listSR = new ArrayList<SingleRow>();

        Resources res = c.getResources();
        String[] projecto = res.getStringArray(R.array.projectoA);

        for (int i = 0; i < projecto.length; i++) {
            listSR.add(new SingleRow(projecto[i]));
        }
    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return listSR.size();
    }

    @Override
    public Object getItem(int i) {
        // TODO Auto-generated method stub
        return listSR.get(i);
    }

    @Override
    public long getItemId(int i) {
        // TODO Auto-generated method stub
        return i;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {// call to each row
        // TODO Auto-generated method stub

        // Inflater -> goes toxml, reads properties and creates the object with those properties!
        // new object everytime: layout inflater || same object everytime:
        // findViewById
        LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View row = inflater.inflate(R.layout.single_row, viewGroup, false);// ref to RelativeLayout
        TextView tV = (TextView) row.findViewById(R.id.textView1);
        CheckBox cBx = (CheckBox) row.findViewById(R.id.checkbox);

        SingleRow temp = listSR.get(i);

        tV.setText(temp.projecto);

        return row;
    }

}

}`

如何让特定客户获得项目数组？

Client A获取所有projectsA，Client B获取所有projectsB等等。

我现在该怎么办？

提前致谢！

Answer 1

修改您的适配器添加此方法：

public void swapData(int resId) {
   Resources res = c.getResources();
   String[] projecto = res.getStringArray(resId);
   listSR.clear();
   for (int i = 0; i < projecto.length; i++) {
      listSR.add(new SingleRow(projecto[i]));

   notifyDatasetChanged(); 
}

然后在你的onItemSelectedListener：

@Override
public void onItemSelected(AdapterView<?> parent, View view, int position,
    long id) {
    Adaptor adapter = (Adaptor)listView.getAdapter();
    switch (position) {
       case 0: {
          adapter.swapData(R.array.projectoA);
          break;
       }
       /* and so on*/
    }
}

Answer 2

   @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position,
                long id) {
            adapter2.clear();
            switch (position) {
            case 0:
                // fill adapter2 with client A
                break;

            case 1:
                // fill adapter 2 with clientB 
                break;
            }

        }

每次单击列表视图中的项目时，都会检查单击的位置并重新调整适配器的内容

如何使`Spinner onItemSelected（）`从`strings.xml`中的数组更新`ListView`项？

2 个答案: