我想要使用活動組 - 因爲我使用標籤,並希望有加載時的標籤和列表項被點擊後的活動。但我得到在下面的行nullpointerexception:Android ActivityGroup - 空指針異常
View view1 = S1_Group.group.getLocalActivityManager()
.startActivity("S1", intent)
.getDecorView();
代碼是..。
lv.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Intent intent = new Intent(getApplicationContext(), S1.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
Log.d("test","Before view");
try{
View view1 = S1_Group.group.getLocalActivityManager()
.startActivity("S1", intent)
.getDecorView();
Settings_Group.group.setContentView(view1);
}
catch (Exception e){
Log.e("test","view failded:"+e);
}
....
更新:這是我的小組活動是如何。我找不到什麼問題,
public class S1_Group extends ActivityGroup {
public static S1_Group group;
private ArrayList<View> history;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
this.history = new ArrayList<View>();
group = this;
View view = getLocalActivityManager().startActivity("F1",
new Intent(this, F1.class).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)).getDecorView();
setContentView(view);
}
}
基本調試步驟:如果你在一條有多條鏈的線上獲得NPE「。」調用,例如().b().c().d()`,那麼這些方法中的其中一個可能返回null。將此線路拆分爲單個呼叫,例如`X x = a(); Y y = x.b(); Z z = y.c(); W w = z.d()`,並添加檢查以查看哪一個返回null。 – 2011-02-06 20:35:55