1. 程式人生 > >Android ListView動態刷新某項Item

Android ListView動態刷新某項Item

ack static auto ids avi idt ica horizon extc

使用ViewHolder來刷新某項數據,而不用每次都全部刷新數據。

繼承BaseAdapter,新建ViewHolder類。

public class TestListAdapter extends BaseAdapter {
    private Context mContext;

    private List<String> strList;

    public TestListAdapter(Context context, List<String> list) {
        super();
        this.mContext = context;
        
this.strList = list; } @Override public int getCount() { // TODO Auto-generated method stub return strList.size(); } @Override public Object getItem(int position) { // TODO Auto-generated method stub return position; } @Override
public long getItemId(int position) { // TODO Auto-generated method stub return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { // TODO Auto-generated method stub ViewHolder holder = null; if (null
== convertView) { convertView = LayoutInflater.from(mContext).inflate(R.layout.line, null); holder = new ViewHolder(); holder.iDText = (TextView) convertView.findViewById(R.id.textView_id); holder.strText = (TextView) convertView.findViewById(R.id.textView_str); convertView.setTag(holder); } else { holder = (ViewHolder) convertView.getTag(); } holder.iDText.setText(position + ""); String str = strList.get(position); holder.strText.setText(str); return convertView; } private static class ViewHolder { private TextView iDText; private TextView strText; } public void updataView(int posi, ListView listView) { int visibleFirstPosi = listView.getFirstVisiblePosition(); int visibleLastPosi = listView.getLastVisiblePosition(); if (posi >= visibleFirstPosi && posi <= visibleLastPosi) { View view = listView.getChildAt(posi - visibleFirstPosi); ViewHolder holder = (ViewHolder) view.getTag(); String txt = holder.strText.getText().toString(); txt = txt + "++;"; holder.strText.setText(txt); strList.set(posi, txt); } else { String txt = strList.get(posi); txt = txt + "++;"; strList.set(posi, txt); } } }

在Activity中,調用updateView()方法,刷新數據。

public class MainActivity extends Activity {
    private MainActivity mContext;

    private EditText idEdit;

    private TextView textView;

    private List<String> strList = new ArrayList<String>();
    private ListView listView;
    private TestListAdapter ListAdapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mContext = this;

        for (int i = 0; i < 100; i++) {
            strList.add("test data");
        }

        idEdit = (EditText) findViewById(R.id.edittext_id);
        textView = (TextView) findViewById(R.id.textview_modify);

        listView = (ListView) findViewById(R.id.listview);
        ListAdapter = new TestListAdapter(mContext, strList);
        listView.setAdapter(ListAdapter);

        //動態刷新
        textView.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                String idStr = idEdit.getText().toString();
                int idInt = Integer.parseInt(idStr);
                ListAdapter.updataView(idInt, listView);//動態修改
            }
        });
    }
}

給出布局文件:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#FFFFFF"
    android:orientation="vertical" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="40dp"
        android:orientation="horizontal" >

        <EditText
            android:id="@+id/edittext_id"
            android:layout_width="200dp"
            android:layout_height="wrap_content"
            android:hint="put modify id" />

        <TextView
            android:id="@+id/textview_modify"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="動態修改"
            android:textColor="#123456" />
    </LinearLayout>

    <ListView
        android:id="@+id/listview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
    </ListView>

</LinearLayout>

Android ListView動態刷新某項Item