我有三个片段，第二个和第三个片段，在各自的布局中都有一个listView。
最初，“second and third Frament”的listView填充了相同的项目。换句话说，最初是listView的 第二个片段和第三个片段，包含以下内容：CB：是checkBox和IV：是ImageView，t是：textview，而SaveButton是一个buton
t1........CB.......IV
t2........CB.......IV
t3........CB.......IV
t4........CB.......IV
t5........CB.......IV
t6........CB.......IV
SaveButton
我想要做的是，当我在第二个片段中并从listView中选择一个项目“使用复选框”并单击“保存”按钮，然后，我选择的那个项目应该被删除来自第三个片段中的listView。
为了实现这一点，在getview（）中，我检查了是否从第二个片段的listView中检查了checkBox，如果选中它，我添加了检查的项目 到列表。如getView（）所示：
第二段片段：
private void setUpListView() {
// TODO Auto-generated method stub
this.topicsList = new ArrayList<String>();
for (int i = 0; i < this.topics.length; i++) {
this.topicsList.add(topics[i]);
}
this.adapter = new ListViewAdapter(getActivity(), this.topicsList, ECO_FRAG_ID);
this.listView.setAdapter(adapter);
}
第三段片段：
private void setUpListView() {
// TODO Auto-generated method stub
this.topicsList = new ArrayList<String>();
for (int i = 0; i < this.topics.length; i++) {
this.topicsList.add(topics[i]);
}
this.adapter = new ListViewAdapter(getActivity(), this.topicsList, LOGGER_FRAG_ID);
this.listView.setAdapter(adapter);
}
BaseAdapter ：
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
if (convertView == null) {
LayoutInflater layoutinflater = (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
convertView = layoutinflater.inflate(R.layout.list_items_layout, null);
}
if (this.checkedItemsList1 == null) {
this.checkedItemsList1 = new ArrayList<String>();
}
if (this.checkedItemsList2 == null) {
this.checkedItemsList2 = new ArrayList<String>();
}
final TextView tv = (TextView) convertView.findViewById(R.id.tvlist_topic);
final CheckBox cb = (CheckBox) convertView.findViewById(R.id.cbList_hook);
final ImageView iv = (ImageView) convertView.findViewById(R.id.ivList_delete);
tv.setText(this.topicsList.get(position));
if (cb.isChecked() && (this.id == 1) ) {
this.checkedItemsList1.add(this.topicsList.get(position));
this.setCheckedItemsList1(this.checkedItemsList1);
}
if (cb.isChecked() && (this.id == 2) ) {
this.checkedItemsList2.add(this.topicsList.get(position));
this.setCheckedItemsList2(this.checkedItemsList2);
}
iv.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (cb.isChecked())
cb.setChecked(false);
topicsList.remove(position);
notifyDataSetChanged();
}
});
return convertView;
}
我创建了一个接口，它在onAttach（）中初始化，并在我点击secondFragment中的savebuton时调用：
private OnClickListener btnSaveListener = new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Toast.makeText(getActivity(), "Save to SQLite", Toast.LENGTH_SHORT).show();
Log.d(TAG, "size: " + adapter.getCheckedItemsList1().size());
iCSC.onCheckedStateChanged(adapter.checkedItemsList1, ECO_FRAG_ID);
}
};
这个表面，mainActivity实现它，并且在接口的实现中，我将列表f从第二个片段传递到第三个片段到第三个片段 通过第三个fragmet中的公共方法片段更新列表，然后将列表分配给适配器，如下所示：
@Override
public void onCheckedStateChanged(ArrayList<String> list, int id) {
// TODO Auto-generated method stub
switch (id) {
case 1:
((Logger_Settings_Frag) this.fragList.get(2)).updateTopicList(list);
break;
case 2:
break;
}
}
**updateTopicList in the third fragment**
public void updateTopicList(ArrayList<String> list) {
for (String str : list) {
this.topicsList.remove(str);
}
this.adapter = new ListViewAdapter(getActivity(), this.topicsList, LOGGER_FRAG_ID);
this.listView.setAdapter(adapter);
}
第三个片段中的updateTopicList
public void updateTopicList(ArrayList<String> list) {
for (String str : list) {
this.topicsList.remove(str);
}
this.adapter = new ListViewAdapter(getActivity(), this.topicsList, LOGGER_FRAG_ID);
this.listView.setAdapter(adapter);
}
当我运行该代码时，在第二个片段的saveButton侦听器中，log.d消息显示应该包含已检查项目的列表大小是零大小？！
请查看代码，让我知道我错过了什么？
答案 0 :(得分：0)
试试这个：它是一个带有两个片段的Project OneActivity示例： public ArrayList myBeansList_frgnt1; public ArrayList myBeansList_frgnt2; 通过单击保存按钮迭代myBeansList_frgnt1并检查是否选择了任何项目。如果选择了item，我将该项添加到myBeansList_frgnt2。在fragment2中显示。
MainActivity：
public class MainActivity extends FragmentActivity {
private FragmentManager mFragmentManager;
private MyFragment1 myFragment1;
public ArrayList<MyBean> myBeansList_frgnt1;
public ArrayList<MyBean> myBeansList_frgnt2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mFragmentManager = getSupportFragmentManager();
myBeansList_frgnt1 = new ArrayList<MyBean>();
myBeansList_frgnt2 = new ArrayList<MyBean>();
}
@Override
protected void onResume() {
super.onResume();
myFragment1 = new MyFragment1();
FragmentTransaction mTransaction = mFragmentManager.beginTransaction();
mTransaction.replace(R.id.framid, myFragment1, "applock").commit();
}
}
MyBaseAdpter：维护MyBean对象中的状态
@Override
public View getView(int position, View view, ViewGroup parent) {
final ViewHolder holder;
if (view == null) {
holder = new ViewHolder();
view = LayoutInflater.from(mContext).inflate(R.layout.list_item, null);
holder.mTextView = (TextView) view.findViewById(R.id.textView1);
holder.mBox = (CheckBox) view.findViewById(R.id.checkBox1);
holder.mImageView = (ImageView) view.findViewById(R.id.imageView1);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
final MyBean mBean = mBeansList.get(position);
holder.mBox.setOnCheckedChangeListener(null);
holder.mBox.setChecked(mBean.isChecked());
holder.mBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
mBean.setChecked(true);
} else {
mBean.setChecked(false);
}
}
});
// setting text and image
holder.mTextView.setText(mBean.getmName());
holder.mImageView.setImageResource(mBean.getmImgId());
return view;
}
private class ViewHolder {
TextView mTextView;
CheckBox mBox;
ImageView mImageView;
}
片段1：
public class MyFragment1 extends Fragment {
private ListView mListView;
private MyBaseAdpter myBaseAdpter;
private Button mButton;
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_layout, null);
mListView = (ListView) view.findViewById(R.id.listviewid);
mButton = (Button) view.findViewById(R.id.bttnid);
return view;
}
@Override
public void onResume() {
super.onResume();
final MainActivity mActivity = (MainActivity) getActivity();
myBaseAdpter = new MyBaseAdpter(mActivity.myBeansList_frgnt1, getActivity());
mListView.setAdapter(myBaseAdpter);
mButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
int size = mActivity.myBeansList_frgnt1.size();
for (int i = 0; i < size; i++) {
MyBean mMyBean = mActivity.myBeansList_frgnt1.get(i);
if (mMyBean.isChecked()) {
mActivity.myBeansList_frgnt2.add(mMyBean);
}
}
}
});
}
}
Fragment2：
public class MyFragment2 extends Fragment {
private ListView mListView;
private MyBaseAdpter myBaseAdpter;
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_layout, null);
mListView = (ListView) view.findViewById(R.id.listviewid);
return view;
}
@Override
public void onResume() {
super.onResume();
MainActivity mActivity = (MainActivity) getActivity();
myBaseAdpter = new MyBaseAdpter(mActivity.myBeansList_frgnt2, getActivity());
mListView.setAdapter(myBaseAdpter);
}
}
为myBean：
public class MyBean {
private String mName;
private int mImgId;
private boolean isChecked;
public String getmName() {
return mName;
}
public void setmName(String mName) {
this.mName = mName;
}
public int getmImgId() {
return mImgId;
}
public void setmImgId(int mImgId) {
this.mImgId = mImgId;
}
public boolean isChecked() {
return isChecked;
}
public void setChecked(boolean isChecked) {
this.isChecked = isChecked;
}
public MyBean() {
super();
// TODO Auto-generated constructor stub
}
}