以下是我的屏幕截图＃http://imgur.com/hGQCHpk

Question

我很熟悉这种编程语言可以帮助我做些什么。

以下是我的屏幕截图＃http://imgur.com/hGQCHpk

如果单击listview包含的主页片段

，列表视图不会更新

MainActivity.Java

public class MainActivity extends Activity {

private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;

// nav drawer title
private CharSequence mDrawerTitle;

// used to store app title
private CharSequence mTitle;

// slide menu items
private String[] navLogout;
String[] navMenuTitles;
TypedArray navMenuIcons;

ArrayList<NavDrawerItem> navDrawerItems;
private NavDrawerListAdapter adapter;

@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);

    mTitle = mDrawerTitle = getTitle();

    // load slide menu items
    navMenuTitles = getResources().getStringArray(
            R.array.nav_drawer_items_not_login);

    // nav drawer icons from resources
    navMenuIcons = getResources()
            .obtainTypedArray(R.array.nav_drawer_icons);

    mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
    mDrawerList = (ListView) findViewById(R.id.list_slidermenu);

    navDrawerItems = new ArrayList<NavDrawerItem>();

    // adding nav drawer items to array
    // Home
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons
            .getResourceId(0, -1)));
    // login
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[1], navMenuIcons
            .getResourceId(1, -1)));
    // register
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[2], navMenuIcons
            .getResourceId(2, -1)));
    // classic brownies
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[3], navMenuIcons
            .getResourceId(3, -1)));
    // cupcakes
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[4], navMenuIcons
            .getResourceId(3, -1)));
    // cookies
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[5], navMenuIcons
            .getResourceId(3, -1)));
    // feedback
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[6], navMenuIcons
            .getResourceId(4, -1)));
    // about
    navDrawerItems.add(new NavDrawerItem(navMenuTitles[7], navMenuIcons
            .getResourceId(5, -1)));

    // Recycle the typed array
    navMenuIcons.recycle();

    mDrawerList.setOnItemClickListener(new SlideMenuClickListener());

    // setting the nav drawer list adapter
    adapter = new NavDrawerListAdapter(getApplicationContext(),
            navDrawerItems);
    mDrawerList.setAdapter(adapter);

    // enabling action bar app icon and behaving it as toggle button
    getActionBar().setDisplayHomeAsUpEnabled(true);
    getActionBar().setHomeButtonEnabled(true);

    mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
            R.drawable.ic_drawer, // nav menu toggle icon
            R.string.app_name, // nav drawer open - description for
                                // accessibility
            R.string.app_name // nav drawer close - description for
                                // accessibility
    ) {
        public void onDrawerClosed(View view) {
            getActionBar().setTitle(mTitle);
            // calling onPrepareOptionsMenu() to show action bar icons
            invalidateOptionsMenu();
        }

        public void onDrawerOpened(View drawerView) {
            getActionBar().setTitle(mDrawerTitle);
            // calling onPrepareOptionsMenu() to hide action bar icons
            invalidateOptionsMenu();
        }
    };
    mDrawerLayout.setDrawerListener(mDrawerToggle);

    if (savedInstanceState == null) {

        displayView(0);

    }

}

/**
 * Slide menu item click listener
 * */
private class SlideMenuClickListener implements
        ListView.OnItemClickListener {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position,
            long id) {
        // display view for selected nav drawer item

        displayView(position);

    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.main, menu);

    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // toggle nav drawer on selecting action bar app icon/title

    if (mDrawerToggle.onOptionsItemSelected(item)) {
        return true;
    }
    Fragment fragment = null;
    Fragment newFragment = new AboutFragment();
    // Handle action bar actions click
    switch (item.getItemId()) {
    case R.id.action_search:
        Toast.makeText(this, "search selected", Toast.LENGTH_SHORT).show();

        break;

    case R.id.action_shoppingcart:




            FragmentTransaction transaction = getFragmentManager()
                    .beginTransaction();

            transaction.replace(R.id.frame_container, newFragment,
                    "AboutFragment");

            transaction.commit();

            getActionBar().setTitle("Shopping cart");



        return true;

    default:
        break;

    }
    return true;
}

/* *
 * Called when invalidateOptionsMenu() is triggered
 */
@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    // if nav drawer is opened, hide the action items
    boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);

    menu.findItem(R.id.action_search).setVisible(!drawerOpen);
    menu.findItem(R.id.action_shoppingcart).setVisible(!drawerOpen);

    return super.onPrepareOptionsMenu(menu);
}

/**
 * Diplaying fragment view for selected nav drawer list item
 * */
private void displayView(int position) {
    // update the main content by replacing fragments
    Fragment fragment = null;
    switch (position) {
    case 0:

        fragment = new HomeFragment();

        break;
    case 1:
        fragment = new LoginFragment();
        break;
    case 2:
        fragment = new RegisterFragment();
        break;
    case 3:
        fragment = new ClassicBrowniesFragment();

        break;
    case 4:
        fragment = new CupcakesFragment();
        break;
    case 5:
        fragment = new CookiesFragment();
        break;
    case 6:
        fragment = new FeedbackFragment();
        break;
    case 7:
        fragment = new AboutFragment();
        break;

    default:
        break;
    }

    if (fragment != null) {
        FragmentManager fragmentManager = getFragmentManager();
        fragmentManager.beginTransaction()
                .replace(R.id.frame_container, fragment).commit();

        // update selected item and title, then close the drawer

        mDrawerList.setItemChecked(position, true);
        mDrawerList.setSelection(position);
        setTitle(navMenuTitles[position]);
        mDrawerLayout.closeDrawer(mDrawerList);

    }

    else {
        // error in creating fragment
        Log.e("MainActivity", "Error in creating fragment");
    }
}

@Override
public void setTitle(CharSequence title) {
    mTitle = title;
    getActionBar().setTitle(mTitle);
}

/**
 * When using the ActionBarDrawerToggle, you must call it during
 * onPostCreate() and onConfigurationChanged()...
 */

@Override
protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    // Sync the toggle state after onRestoreInstanceState has occurred.
    mDrawerToggle.syncState();
}

@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    // Pass any configuration change to the drawer toggls
    mDrawerToggle.onConfigurationChanged(newConfig);
}
}

HomeFragment.java

public class HomeFragment extends Fragment implements OnItemClickListener {

String[] member_names;
TypedArray product_icons;
String[] statues;
String[] contactType;

List<RowItem> rowItems;
ListView mylistview;
CustomAdapter myadapter;
CustomAdapter newadapter;

EditText editsearch;

public HomeFragment() {
}

View rootView;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    rootView = inflater.inflate(R.layout.fragment_home, container, false);

    rowItems = new ArrayList<RowItem>();

    member_names = getResources().getStringArray(R.array.Member_names);

    product_icons = getResources().obtainTypedArray(R.array.product_icons);

    statues = getResources().getStringArray(R.array.statues);

    for (int i = 0; i < member_names.length; i++) {
        RowItem item = new RowItem(member_names[i],
                product_icons.getResourceId(i, -1), statues[i]);
        rowItems.add(item);
    }

    mylistview = (ListView) rootView.findViewById(R.id.list);

    mylistview.setItemsCanFocus(true);
    //
    final CustomAdapter adapter = new CustomAdapter(getActivity(), rowItems);
    mylistview.setAdapter(adapter);
    product_icons.recycle();
    mylistview.setOnItemClickListener(this);

    mylistview.setScrollingCacheEnabled(false);

    mylistview.invalidateViews();
    adapter.notifyDataSetChanged();

    this.setRetainInstance(true);

    return rootView;

}

public void updateList(List adapter) {
    mylistview = (ListView) rootView.findViewById(R.id.list);
    mylistview.setAdapter((ListAdapter) adapter);
}

@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
        long id) {

    String member_name = rowItems.get(position).getMember_name();
    int product_icons = rowItems.get(position).getProfile_pic_id();
    String status = rowItems.get(position).getStatus();

    RowItem item = rowItems.get(position);

    Intent intent = new Intent(getActivity(), HomeFragment.class);
    intent.putExtra("member_name", member_name);
    intent.putExtra("product_icons", product_icons);
    intent.putExtra("status", status);

    rowItems.remove(item);

    newadapter = new CustomAdapter(getActivity(), rowItems);
    mylistview.setAdapter(newadapter);

    newadapter.notifyDataSetChanged();

    Toast.makeText(getActivity().getApplicationContext(),
            "Added to Cart: " + member_name, Toast.LENGTH_SHORT).show();

    }
}

CustomAdapter.java

public class CustomAdapter extends BaseAdapter {

HomeFragment home = new HomeFragment();

Context context;
List<RowItem> rowItems;

public CustomAdapter(Context context, List<RowItem> rowItems) {
    this.context = context;
    this.rowItems = rowItems;

}

public CustomAdapter() {
    // TODO Auto-generated constructor stub
}

@Override
public int getCount() {
    return rowItems.size();
}

@Override
public Object getItem(int position) {
    return rowItems.get(position);
}

@Override
public long getItemId(int position) {
    return rowItems.indexOf(getItem(position));
}

/* private view holder class */
private class ViewHolder {
    ImageView product_icons;
    TextView member_name;
    TextView status;
    Button addtocart;
}

ViewHolder holder = null;

@Override
public View getView(final int position, View convertView, ViewGroup parent) {

    LayoutInflater mInflater = (LayoutInflater) context
            .getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
    if (convertView == null) {
        convertView = mInflater.inflate(R.layout.list_item, null);
        holder = new ViewHolder();

        holder.member_name = (TextView) convertView
                .findViewById(R.id.member_name);
        holder.product_icons = (ImageView) convertView
                .findViewById(R.id.product_icons);
        holder.status = (TextView) convertView.findViewById(R.id.status);
        holder.addtocart = (Button) convertView
                .findViewById(R.id.btnaddtocart);

        RowItem row_pos = rowItems.get(position);

        holder.product_icons.setImageResource(row_pos.getProfile_pic_id());
        holder.member_name.setText(row_pos.getMember_name());
        holder.status.setText(row_pos.getStatus());
        holder.addtocart.setText(" add to cart");

        convertView.setTag(holder);

    } else {

        holder = (ViewHolder) convertView.getTag();

    }

    return convertView;
    }

}

RowItem.java

 public class RowItem {

 private String member_name;
 private int profile_pic_id;
 private String status;



 public RowItem(String member_name, int profile_pic_id, String status) {

  this.member_name = member_name;
  this.profile_pic_id = profile_pic_id;
  this.status = status;



 }

 public String getMember_name() {
  return member_name;
 }

 public void setMember_name(String member_name) {
  this.member_name = member_name;
 }

 public int getProfile_pic_id() {
  return profile_pic_id;
 }

 public void setProfile_pic_id(int profile_pic_id) {
  this.profile_pic_id = profile_pic_id;
 }

 public String getStatus() {
  return status;
 }

 public void setStatus(String status) {
  this.status = status;
 }

 }

请为我的软件工程主题帮助我，希望有人能帮助我。

Answer 1

您好像只是删除了保存数据的视图，而不是实际更改基础数据集。如果您希望删除该项目，请致电rowItems.remove()，但请记住重新加载片段的时间，例如点击Home导航选项时HomeFragment.createView()中的代码已运行。

在该代码中，您可以看到rowItems在此处初始化

member_names = getResources().getStringArray(R.array.Member_names);

for (int i = 0; i < member_names.length; i++) {
    RowItem item = new RowItem(member_names[i],
            product_icons.getResourceId(i, -1), statues[i]);
    rowItems.add(item);
}

因此，除非您删除Member_names数组资源中的项目，否则每次重新创建片段时都会显示该项目。

当我删除它上面的项目时更新列表视图

以下是我的屏幕截图＃http://imgur.com/hGQCHpk

MainActivity.Java

HomeFragment.java

CustomAdapter.java

RowItem.java

1 个答案: