今天遇到这么个需求，需要在运行时动态添加ListView的item，看起来很简单，实际操作过程中却遇到了麻烦，下面揭秘在ListView等AdapterView上动态添加删除项的陷阱
如何避开在ListView等AdapterView上动态添加删除项的陷阱，下面就为大家分享，具体内容如下
首先，定义如下array资源，作为列表的加载内容：
<resources> <string name="app_name">MyListView</string> <string-array name="language"> <item>Java</item> <item>C</item> <item>C++</item> <item>PHP</item> </string-array>
然后简单地写下布局文件，由于我需要不管列表有多长，始终在底部显示编辑框和按钮，所以将ListView中的layout_weight设为1。
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://www.easck.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <ListView android:id="@android:id/list" android:layout_width="fill_parent" android:layout_height="0dip" android:layout_weight="1" /> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal"> <EditText android:id="@+id/addLangEdit" android:layout_width="200px" android:layout_height="wrap_content" /> <Button android:id="@+id/addButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="添加" /> </LinearLayout> </LinearLayout>
最后添上Activity的代码，似乎没什么问题了，运行一下。
public class MyListView extends ListActivity {
private ArrayAdapter<CharSequence> mAdapter;
private ListView mListView;
private EditText mLanguageText;
private Button mAddButton;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mylist1);
//get the view
mListView = getListView();
mLanguageText = (EditText) findViewById(R.id.addLangEdit);
mAddButton = (Button) findViewById(R.id.addButton);
//array adapter created from string array resources
mAdapter = ArrayAdapter.createFromResource(
this,
R.array.language,
android.R.layout.simple_list_item_1);
//set the adapter
mListView.setAdapter(mAdapter);
//add listener
mAddButton.setOnClickListener(mOnClickListener);
}
private OnClickListener mOnClickListener = new View.OnClickListener() {
@Override
public void onClick(View v) {
String text = mLanguageText.getText().toString();
if(null == text || "".equals(text.trim())) {
Toast.makeText(MyListView.this, "输入不能为空", Toast.LENGTH_SHORT).show();
}else {
mAdapter.add(text);
mAdapter.notifyDataSetChanged();
mLanguageText.setText("");
}
}
};
}
