我想添加列表为微调,但我一直都想与在logcat的一个异常说:俊男项目添加到微调
"java.lang.RuntimeException: Unable to start activity ComponentInfo{....}: java.lang.NullPointerException"
在模拟器中,一个对话框出现说该应用程序意外停止,我需要强制关闭。我尝试过不同的事情,但我仍然得到相同的例外。
下面是活动的代码:
public class CreateListActivity extends Activity implements OnClickListener{
/** Called when the activity is first created. */
@Override
protected void onCreate(Bundle savedInstanceState)
{
Spinner categorySpinner = (Spinner)findViewById(R.id.category_Spinner);
CategoryAction categoryAction = new CategoryAction(getBaseContext());
ArrayList<ListCategory> categorylist = new ArrayList<ListCategory>();
ArrayList<String> categoryNames = new ArrayList<String>();
//Get all existing categories.
try
{
categorylist = (ArrayList<ListCategory>) categoryAction.getAllCategories();
}
catch(SQLException e)
{
e.printStackTrace();
}
// Add all existing category names. This will be used to add options to the spinner.
for (ListCategory category : categorylist)
{
categoryNames.add(category.getCategoryName());
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, categoryNames);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
super.onCreate(savedInstanceState);
setContentView(R.layout.createlist);
categorySpinner.setAdapter(adapter);
View addNewListButton = findViewById(R.id.Add_List_button);
addNewListButton.setOnClickListener(this);
}
public void onClick(View v)
{
ListAction listAction = new ListAction(getBaseContext());
EditText listEditText = (EditText)findViewById(R.id.listName);
String newListName = listEditText.getText().toString();
try {
if(!listAction.listExist(newListName)){
listAction.createList(newListName, "To Buy");
}
} catch (SQLException e) {
e.printStackTrace();
}
Intent viewListsIntent = new Intent(this, ItemListActivity.class);
startActivity(viewListsIntent);
}
}
非常感谢!我刚开始使用Android进行开发,但对IDE依然不熟悉。 – k4ru050 2011-06-17 00:55:03