我想要做的是每次在片段抽屉上单击列表项时，在占位符片段中填充新列表。
我所做的是，onClick片段抽屉中的列表项我从其位置值得到它的位置值我在SQlite数据库中得到它的foreignkey_id。并运行查询并根据外键获取结果，并将它们的位置和外键传递给NavigationDrawerFragment中MainActivity中的onNavigationDrawerItemSelected 我不支持的是如何将这些值分配给片段并使片段管理器显示我的值
我无法理解代码的NavigationDrawerItemSelected和placeholderFragments部分 这是MainActivity类
public class MainActivity extends ActionBarActivity implements
NavigationDrawerFragment.NavigationDrawerCallbacks {
/**
* Fragment managing the behaviors, interactions and presentation of the
* navigation drawer.
*/
private NavigationDrawerFragment mNavigationDrawerFragment;
/**
* Used to store the last screen title. For use in
* {@link #restoreActionBar()}.
*/
private CharSequence mTitle;
private Context mContext = this;
Activity mActivity;
String toastMsg = null;
DatabaseHelper db;
TaskListAdapter mAdapter;
ArrayList<Task> task_data = new ArrayList<Task>();
ListView Task_listview;
TaskAdapter taskAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mNavigationDrawerFragment = (NavigationDrawerFragment) getSupportFragmentManager()
.findFragmentById(R.id.navigation_drawer);
mTitle = getTitle();
// Set up the drawer.
mNavigationDrawerFragment.setUp(R.id.navigation_drawer,
(DrawerLayout) findViewById(R.id.drawer_layout));
}
@Override
public void onNavigationDrawerItemSelected(int position, int selectItemid) {
// update the main content by replacing fragments
// FragmentManager fragmentManager = getSupportFragmentManager();
// fragmentManager
// .beginTransaction()
// .replace(R.id.container,
// PlaceholderFragment.newInstance(position + 1)).commit();
try {
task_data.clear();
db = new DatabaseHelper(getApplicationContext());
ArrayList<Task> task_array_from_db = db
.Get_Tasks_Where_FK(selectItemid);
for (int i = 0; i < contact_array_from_db.size(); i++) {
int task_id = task_array_from_db.get(i)._id;
String title = task_array_from_db.get(i).title;
String details = task_array_from_db.get(i).details;
String notes = task_array_from_db.get(i).notes;
Task task = new Task();
task._id = task_id ;
task.title = title;
task.details = details;
task.notes = notes;
task_data.add(task);
db.close();
taskAdapter = new TaskAdapter(mActivity, R.layout.listview_row,
task_data);
Task_listview.setAdapter(taskAdapter);
taskAdapter.notifyDataSetChanged();
}// try
catch (Exception e) {
Log.e("error on fragment", "creating the mainScreen");
}// catch
finally {
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.container, PlaceholderFragment.newInstance( ))
.commit();
}
}
public void onSectionAttached(int number) {
switch (number) {
case 1:
mTitle = getString(R.string.title_section1);
break;
case 2:
mTitle = getString(R.string.title_section2);
break;
case 3:
mTitle = getString(R.string.title_section3);
break;
}
}
public void restoreActionBar() {
ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
actionBar.setDisplayShowTitleEnabled(true);
actionBar.setTitle(mTitle);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
if (!mNavigationDrawerFragment.isDrawerOpen()) {
// Only show items in the action bar relevant to this screen
// if the drawer is not showing. Otherwise, let the drawer
// decide what to show in the action bar.
getMenuInflater().inflate(R.menu.main, menu);
restoreActionBar();
return true;
}
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
} else if (id == R.id.add_list_title) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
/**
* Returns a new instance of this fragment for the given section number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
public static PlaceholderFragment newInstance(Task task) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
fragment.setArguments(args);
return fragment;
}
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
//View rootView = inflater.inflate(R.layout.fragment_main, container,
//false);
View rootView = inflater.inflate(R.layout.main, container,
false);
TextView textView = (TextView) rootView
.findViewById(R.id.user_task_title);
TextView textView1 = (TextView) rootView
.findViewById(R.id.user_task_details);
TextView textView2 = (TextView) rootView
.findViewById(R.id.user_task_notes);
// TextView textView = (TextView)
// rootView.findViewById(R.id.section_label);
// textView.setText(Integer.toString(getArguments().getInt(
// ARG_SECTION_NUMBER)));
return rootView;
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
// ((MainActivity)
// activity).onSectionAttached(getArguments().getInt(
// ARG_SECTION_NUMBER));
}
}
}
这是NavigationDrawerFragment类
public class NavigationDrawerFragment extends Fragment {
DatabaseHelper db;
Activity mActivity;
ArrayList<TaskList> task_title_list = new ArrayList<TaskList>();
TaskListAdapterSimple mAdapter;
Button AddTaskListbtn;
String toastMsg = null;
//private int selCount = 0; // for CAB multi select count
/**
* Remember the position of the selected item.
*/
private static final String STATE_SELECTED_POSITION = "selected_navigation_drawer_position";
/**
* Per the design guidelines, you should show the drawer on launch until the
* user manually expands it. This shared preference tracks this.
*/
private static final String PREF_USER_LEARNED_DRAWER = "navigation_drawer_learned";
/**
* A pointer to the current callbacks instance (the Activity).
*/
private NavigationDrawerCallbacks mCallbacks;
/**
* Helper component that ties the action bar to the navigation drawer.
*/
private ActionBarDrawerToggle mDrawerToggle;
private DrawerLayout mDrawerLayout;
private ListView mDrawerListView;
private View mFragmentContainerView;
private int mCurrentSelectedPosition = 0;
private int itemSelectid = 1;
private boolean mFromSavedInstanceState;
private boolean mUserLearnedDrawer;
public NavigationDrawerFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Read in the flag indicating whether or not the user has demonstrated
// awareness of the
// drawer. See PREF_USER_LEARNED_DRAWER for details.
SharedPreferences sp = PreferenceManager
.getDefaultSharedPreferences(getActivity());
mUserLearnedDrawer = sp.getBoolean(PREF_USER_LEARNED_DRAWER, false);
if (savedInstanceState != null) {
mCurrentSelectedPosition = savedInstanceState
.getInt(STATE_SELECTED_POSITION);
mFromSavedInstanceState = true;
}
// Select either the default item (0) or the last selected item.
selectItem(mCurrentSelectedPosition, itemSelectid);
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// Indicate that this fragment would like to influence the set of
// actions in the action bar.
setHasOptionsMenu(true);
}
public void Set_Refresh_Adapter_Data() { // when called assigns values to
// adapter
task_title_list.clear();
db = new DatabaseHelper(getActivity());
ArrayList<TaskList> task_array_from_db = db.Get_TaskTitleList();
for (int i = 0; i < task_array_from_db.size(); i++) {
int task_id = task_array_from_db.get(i)._id;
String title = task_array_from_db.get(i).title;
TaskList tasklist = new TaskList();
tasklist._id=task_id;
tasklist.title=title;
task_title_list.add(tasklist);
}
db.close();
mAdapter = new TaskListAdapterSimple(getActivity(), R.layout.tasklist_row,
task_title_list);
/**
* list view divider line, color and height
*/
mDrawerListView.setDivider(new ColorDrawable(0x000000));
mDrawerListView.setDividerHeight(1);
mDrawerListView.setAdapter(mAdapter);
mAdapter.notifyDataSetChanged();
}
@SuppressLint({ "InlinedApi", "NewApi" })
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
mDrawerListView = (ListView) inflater.inflate(
R.layout.fragment_navigation_drawer, container, false);
/**
* adding a header to fragment
*/
inflater = this.getLayoutInflater(savedInstanceState);
View header = inflater.inflate(R.layout.drawer_header, null);
mDrawerListView
.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
position--;
int itemSelecteID = mAdapter.getSelectedListId(position);
selectItem(position, itemSelecteID);
}
});
mDrawerListView.setItemChecked(mCurrentSelectedPosition, true);
return mDrawerListView;
}
public boolean isDrawerOpen() {
return mDrawerLayout != null
&& mDrawerLayout.isDrawerOpen(mFragmentContainerView);
}
/**
* Users of this fragment must call this method to set up the navigation
* drawer interactions.
*
* @param fragmentId
* The android:id of this fragment in its activity's layout.
* @param drawerLayout
* The DrawerLayout containing this fragment's UI.
*/
public void setUp(int fragmentId, DrawerLayout drawerLayout) {
mActivity = getActivity();
mFragmentContainerView = getActivity().findViewById(fragmentId);
mDrawerLayout = drawerLayout;
// set a custom shadow that overlays the main content when the drawer
// opens
mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow,
GravityCompat.START);
// set up the drawer's list view with items and click listener
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setHomeButtonEnabled(true);
// ActionBarDrawerToggle ties together the the proper interactions
// between the navigation drawer and the action bar app icon.
mDrawerToggle = new ActionBarDrawerToggle(getActivity(), /* host Activity */
mDrawerLayout, /* DrawerLayout object */
R.drawable.ic_drawer, /* nav drawer image to replace 'Up' caret */
R.string.navigation_drawer_open, /*
* "open drawer" description for
* accessibility
*/
R.string.navigation_drawer_close /*
* "close drawer" description for
* accessibility
*/
) {
@Override
public void onDrawerClosed(View drawerView) {
super.onDrawerClosed(drawerView);
if (!isAdded()) {
return;
}
getActivity().supportInvalidateOptionsMenu(); // calls
// onPrepareOptionsMenu()
}
@Override
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
if (!isAdded()) {
return;
}
if (!mUserLearnedDrawer) {
// The user manually opened the drawer; store this flag to
// prevent auto-showing
// the navigation drawer automatically in the future.
mUserLearnedDrawer = true;
SharedPreferences sp = PreferenceManager
.getDefaultSharedPreferences(getActivity());
sp.edit().putBoolean(PREF_USER_LEARNED_DRAWER, true)
.apply();
}
getActivity().supportInvalidateOptionsMenu(); // calls
// onPrepareOptionsMenu()
}
};
// If the user hasn't 'learned' about the drawer, open it to introduce
// them to the drawer,
// per the navigation drawer design guidelines.
if (!mUserLearnedDrawer && !mFromSavedInstanceState) {
mDrawerLayout.openDrawer(mFragmentContainerView);
}
// Defer code dependent on restoration of previous instance state.
mDrawerLayout.post(new Runnable() {
@Override
public void run() {
mDrawerToggle.syncState();
}
});
mDrawerLayout.setDrawerListener(mDrawerToggle);
}
private void selectItem(int position, int selectItemid) {
mCurrentSelectedPosition = position;
if (mDrawerListView != null) {
mDrawerListView.setItemChecked(position, true);
}
if (mDrawerLayout != null) {
mDrawerLayout.closeDrawer(mFragmentContainerView);
}
if (mCallbacks != null) {
mCallbacks.onNavigationDrawerItemSelected(position, selectItemid);
}
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
mCallbacks = (NavigationDrawerCallbacks) activity;
} catch (ClassCastException e) {
throw new ClassCastException(
"Activity must implement NavigationDrawerCallbacks.");
}
}
@Override
public void onDetach() {
super.onDetach();
mCallbacks = null;
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putInt(STATE_SELECTED_POSITION, mCurrentSelectedPosition);
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Forward the new configuration the drawer toggle component.
mDrawerToggle.onConfigurationChanged(newConfig);
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
// If the drawer is open, show the global app actions in the action bar.
// See also
// showGlobalContextActionBar, which controls the top-left area of the
// action bar.
if (mDrawerLayout != null && isDrawerOpen()) {
inflater.inflate(R.menu.global, menu);
showGlobalContextActionBar();
}
super.onCreateOptionsMenu(menu, inflater);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (mDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
if (item.getItemId() == R.id.action_example) {
Toast.makeText(getActivity(), "Example action.", Toast.LENGTH_SHORT).show();
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* Per the navigation drawer design guidelines, updates the action bar to
* show the global app 'context', rather than just what's in the current
* screen.
*/
private void showGlobalContextActionBar() {
ActionBar actionBar = getActionBar();
actionBar.setDisplayShowTitleEnabled(true);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
actionBar.setTitle(R.string.app_name);
}
private ActionBar getActionBar() {
return ((ActionBarActivity) getActivity()).getSupportActionBar();
}
/**
* Callbacks interface that all activities using this fragment must
* implement.
*/
public static interface NavigationDrawerCallbacks {
/**
* Called when an item in the navigation drawer is selected.
*/
void onNavigationDrawerItemSelected(int position, int selectItem);
}
}
这是我的数据库助手
public class DatabaseHelper extends SQLiteOpenHelper {
// Database Version
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "tasksManager";
// TABLE NAMES
// Tasks table
// tasks has Auto inc. id, title, details and notes
private static final String TABLE_TASKS = "tasks";
// Task List Table
// task list has Auto inc. id and a title
private static final String TABLE_TASK_LIST = "task_list";
// Users Table
// task list has Auto inc. id name and a email
private static final String TABLE_USERS = "users";
// TABLE NAMES
// Tasks Table Columns names
private static final String KEY_PK = "_id";
private static final String KEY_TITLE = "title";
private static final String KEY_DETAILS = "details";
private static final String KEY_NOTES = "notes";
private static final String KEY_FK_TASKLIST_ID = "fk_tasklist_id";
private final ArrayList<Task> task_list = new ArrayList<Task>();
// Task List Table Columns names
// id and title and as above
private final ArrayList<TaskList> task_title_list = new ArrayList<TaskList>();
// SQLite Create Queries
// Tasks Table
private static final String CREATE_TASKS_TABLE = "CREATE TABLE "
+ TABLE_TASKS
+ "("
+ KEY_PK
+ " INTEGER PRIMARY KEY AUTOINCREMENT," + KEY_TITLE + " TEXT,"
+ KEY_DETAILS + " TEXT," + KEY_NOTES + " TEXT,"
+ KEY_FK_TASKLIST_ID + " INTEGER,"
+ " FOREIGN KEY ("+ KEY_FK_TASKLIST_ID + ")"
+ "REFERENCES "
+ TABLE_TASK_LIST + "("+ KEY_PK + ")"
+ ")";
private static final String CREATE_TASK_LIST_TABLE = "CREATE TABLE "
+ TABLE_TASK_LIST + "(" + KEY_PK
+ " INTEGER PRIMARY KEY AUTOINCREMENT," + KEY_TITLE + " TEXT" + ")";
public DatabaseHelper(Context cContext) {
super(cContext, DATABASE_NAME, null, DATABASE_VERSION);
}
// Creating Tables
@Override
public void onCreate(SQLiteDatabase db) {
try {
db.execSQL(CREATE_TASKS_TABLE);// create task table
} catch (Exception e) {
Log.e("onCreate Error", "TASKS_TABLE not created");
}
try {
db.execSQL(CREATE_TASK_LIST_TABLE);// create task list table
} catch (Exception e) {
Log.e("onCreate Error", "TASK_LIST_TABLE not created");
}
}
// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// Drop older table if existed
try {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_TASKS);// Drop Task Table
db.execSQL("DROP TABLE IF EXISTS " + TABLE_TASK_LIST);// Drop Task
onCreate(db);// Create tables again
} catch (Exception e) {
Log.e("Database onUpgrade", "not created");
}
}
/**
* All CRUD FOR TASK(Create, Read, Update, Delete) Operations
*/
// Add new Task
public void Add_Task(Task task) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_TITLE, task.title);
values.put(KEY_DETAILS, task.details);
values.put(KEY_NOTES, task.notes);
values.put(KEY_FK_TASKLIST_ID, task.fk_tasklist_id);
db.insert(TABLE_TASKS, null, values);
db.close();
}
// Delete a Task
public void Delete_Task(int id) {
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_TASKS, KEY_PK + " = ?",
new String[] { String.valueOf(id) });
db.close();
}
// Updating a Task
public int Update_Task(Task task) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_TITLE, task.title);
values.put(KEY_DETAILS, task.details);
values.put(KEY_NOTES, task.notes);
return db.update(TABLE_TASKS, values, KEY_PK + " = ?",
new String[] { String.valueOf(task._id) });// updating row
}
// Getting single Task
Task Get_Task(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_TASKS, new String[] { KEY_PK, KEY_TITLE,
KEY_DETAILS, KEY_NOTES,KEY_FK_TASKLIST_ID }, KEY_PK + "=?",
new String[] { String.valueOf(id) }, null, null, null, null);
if (cursor != null)
cursor.moveToFirst();
Task task = new Task(
Integer.parseInt(cursor.getString(0)),
cursor.getString(1),cursor.getString(2),
cursor.getString(3),
Integer.parseInt(cursor.getString(4))
);
// return Task
cursor.close();
db.close();
return task;
}
// Getting All Tasks
public ArrayList<Task> Get_Tasks() {
try {
task_list.clear();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_TASKS;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Task task = new Task();
task._id=(Integer.parseInt(cursor.getString(0)));
task.title=(cursor.getString(1));
task.details =(cursor.getString(2));
task.notes=(cursor.getString(3));
// task.fk_tasklist_id=(cursor.getString(4));
// Adding Task to list
task_list.add(task);
} while (cursor.moveToNext());
}
// return Task list
cursor.close();
db.close();
return task_list;
} catch (Exception e) {
// TODO: handle exception
Log.e("all_Task", "DBHelper GetTasks" + e);
}
return task_list;
}
// Getting Tasks Count
public int Get_Total_Tasks() {
String countQuery = "SELECT * FROM " + TABLE_TASKS;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
cursor.close();
// return count
return cursor.getCount();
}
// Getting All Tasks
public ArrayList<Task> Get_Tasks_Where_FK(int id) {
try {
task_list.clear();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_TASKS + " WHERE " + KEY_FK_TASKLIST_ID + " = " + id;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Task task = new Task();
task._id=(Integer.parseInt(cursor.getString(0)));
task.title=(cursor.getString(1));
task.details =(cursor.getString(2));
task.notes=(cursor.getString(3));
task.fk_tasklist_id=(Integer.parseInt(cursor.getString(4)));
// Adding Task to list
task_list.add(task);
} while (cursor.moveToNext());
}
// return Task list
cursor.close();
db.close();
return task_list;
} catch (Exception e) {
// TODO: handle exception
Log.e("all_Task", "DBHelper GetTasks" + e);
}
return task_list;
}
/**
* All CRUD FOR TASK LIST(Create, Read, Update, Delete) Operations
*/
// Add a TaskList
public void Add_TaskList(TaskList tasklist) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_TITLE, tasklist.title);
db.insert(TABLE_TASK_LIST, null, values);
db.close();
}
// Delete a TaskList
public void Delete_TaskList(int id) {//recento
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_TASK_LIST, KEY_PK + " = ?",
new String[] { String.valueOf(id) });
db.close();
}
// Updating single Task
public int Update_TaskList(TaskList tasklist) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_TITLE, tasklist.title);
return db.update(TABLE_TASK_LIST, values, KEY_PK + " = ?",
new String[] { String.valueOf(tasklist._id) });
}
// Getting All TasksLists
public ArrayList<TaskList> Get_TaskTitleList() {
try {
task_title_list.clear();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_TASK_LIST;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
TaskList tasklist = new TaskList();
tasklist._id=(Integer.parseInt(cursor.getString(0)));
tasklist.title=(cursor.getString(1));
// Adding Task to list
task_title_list.add(tasklist);
} while (cursor.moveToNext());
}
// return Task list
cursor.close();
db.close();
return task_title_list;
} catch (Exception e) {
// TODO: handle exception
Log.e("all_TaskTitleList", "DBHelper GetTaskTitleList" + e);
}
return task_title_list;
}
// Getting single TaskList
TaskList Get_TaskList(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_TASK_LIST, new String[] { KEY_PK,
KEY_TITLE }, KEY_PK + "=?",
new String[] { String.valueOf(id) }, null, null, null, null);
if (cursor != null)
cursor.moveToFirst();
TaskList tasklist = new TaskList(Integer.parseInt(cursor.getString(0)),
cursor.getString(1));// return TaskList
cursor.close();
db.close();
return tasklist;
}
// Getting Tasks Count
public int Get_Total_TaskList() {
String countQuery = "SELECT * FROM " + TABLE_TASK_LIST;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
cursor.close();
// return count
return cursor.getCount();
}
}
这是我的适配器
public class TaskAdapter extends ArrayAdapter<Task> {
Activity activity;
NavigationDrawerFragment navigationDrawerFragment;
int layoutResourceId;
Task user;
ArrayList<Task> data = new ArrayList<Task>();
private HashMap<Integer, Boolean> mSelection = new HashMap<Integer, Boolean>();
public TaskAdapter(Activity act, int layoutResourceId, ArrayList<Task> data) {
super(act, layoutResourceId, data);
this.layoutResourceId = layoutResourceId;
this.activity = act;
this.data = data;
notifyDataSetChanged();
}
public Task getSingularSelectedTask() {
if (mSelection.size() == 1) {
for (Integer temp : getCurrentCheckedPosition())
return data.get(temp);
}
return null;
}
public ArrayList<Integer> getSelectedTasks() {
ArrayList<Integer> temp = new ArrayList<Integer>();
for (int i = 0; i < data.size(); i++) {
if (isPositionChecked(i)) {
temp.add(data.get(i)._id);
}
}
return temp;
}
public void setNewSelection(int position, boolean value) {
mSelection.put(position, value);
notifyDataSetChanged();
}
public boolean isPositionChecked(int position) {
Boolean result = mSelection.get(position);
return result == null ? false : result;
}
public Set<Integer> getCurrentCheckedPosition() {
return mSelection.keySet();
}
public void removeSelection(int position) {
mSelection.remove(position);
notifyDataSetChanged();
}
public void clearSelection() {
mSelection = new HashMap<Integer, Boolean>();
notifyDataSetChanged();
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
UserHolder holder = null;
if (row == null) {
LayoutInflater inflater = LayoutInflater.from(activity);
// LayoutInflater inflater =
// LayoutInflater.from(navigationDrawerFragment);
row = inflater.inflate(layoutResourceId, parent, false);
holder = new UserHolder();
holder.title = (TextView) row.findViewById(R.id.user_task_title);
holder.details = (TextView) row
.findViewById(R.id.user_task_details);
holder.notes = (TextView) row.findViewById(R.id.user_task_notes);
row.setTag(holder);
} else {
holder = (UserHolder) row.getTag();
}
row.setBackgroundColor(activity.getResources().getColor(
android.R.color.background_light)); // default color
if (mSelection.get(position) != null) {
row.setBackgroundColor(activity.getResources().getColor(
android.R.color.holo_blue_light));
}
user = data.get(position);
holder.title.setText(user.title);
holder.details.setText(user.details);
holder.notes.setText(user.notes);
return row;
}
class UserHolder {
TextView title;
TextView details;
TextView notes;
}
}
答案 0 :(得分：0)
这解决了我的问题
public void onNavigationDrawerItemSelected(int position, int selectItemid) {
// update the main content by replacing fragments
task_data.clear();
本节与上面相同，直到这里，调用db for loop和asssignment
task_data.add(task);
db.close();
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager
.beginTransaction()
.replace(
R.id.container,
PlaceholderFragment
.newInstance(task_data, this)).commit();
}
}
//占位符片段中的这些更改
public static PlaceholderFragment newInstance(
ArrayList<Task> task_data, Activity activity) {
PlaceholderFragment fragment = new PlaceholderFragment();
mActivity = activity;
data = task_data;
return fragment;
}
@SuppressLint("NewApi") @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container,
false);
Task_listview = (ListView) rootView.findViewById(R.id.list);
taskAdapter = new TaskAdapter(mActivity, R.layout.listview_row,
data);
Task_listview.setAdapter(taskAdapter);
taskAdapter.notifyDataSetChanged();
return rootView;
}