Fragment to fragment communication within a NavigationDrawer - android

In my app, I have a NavigationDrawer in my app that has two fragments I want to display (Fragment1 and Fragment2) in a MainActivity. I have a menu item in my ToolBar in Fragment 1 when clicked I want to my MainActivity to switch to Fragment2 and have the NavigationView reflect the UI changes.
public class MainActivity extends AppCompatActivity {
private DrawerLayout mDrawer;
private Toolbar toolbar;
private NavigationView nvDrawer;
private ActionBarDrawerToggle drawerToggle;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction().replace(R.id.flContent, new BookListFragment()).commit();
}
// Set a Toolbar to replace the ActionBar.
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// Find our drawer view
mDrawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawerToggle = setupDrawerToggle();
// Tie DrawerLayout events to the ActionBarToggle
mDrawer.addDrawerListener(drawerToggle);
// Find our drawer view
nvDrawer = (NavigationView) findViewById(R.id.nvView);
// Setup drawer view
setupDrawerContent(nvDrawer);
}
#Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
// Sync the toggle state after onRestoreInstanceState has occurred.
drawerToggle.syncState();
}
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Pass any configuration change to the drawer toggles
drawerToggle.onConfigurationChanged(newConfig);
}
private ActionBarDrawerToggle setupDrawerToggle() {
// NOTE: Make sure you pass in a valid toolbar reference. ActionBarDrawToggle() does not require it
// and will not render the hamburger icon without it.
return new ActionBarDrawerToggle(this, mDrawer, toolbar, R.string.drawer_open, R.string.drawer_close);
}
private void setupDrawerContent(NavigationView navigationView) {
navigationView.setNavigationItemSelectedListener(
new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
selectDrawerItem(menuItem);
return true;
}
});
}
public void selectDrawerItem(MenuItem menuItem) {
// Create a new fragment and specify the fragment to show based on nav item clicked
Fragment fragment = null;
Class fragmentClass;
switch (menuItem.getItemId()) {
case R.id.book_list_fragment:
fragmentClass = BookListFragment.class;
break;
case R.id.discover_fragment:
fragmentClass = DiscoverFragment.class;
break;
default:
fragmentClass = BookListFragment.class;
}
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
// Insert the fragment by replacing any existing fragment
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flContent, fragment).commit();
// Highlight the selected item has been done by NavigationView
menuItem.setChecked(true);
// Set action bar title
setTitle(menuItem.getTitle());
// Close the navigation drawer
mDrawer.closeDrawers();
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// The action bar home/up action should open or close the drawer.
switch (item.getItemId()) {
case android.R.id.home:
mDrawer.openDrawer(GravityCompat.START);
return true;
}
if (drawerToggle.onOptionsItemSelected(item)) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Fragment Code
public class BookListFragment extends Fragment {
...
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.action_insert_dummy_data:
insertBook();
return true;
case R.id.action_delete_all_entries:
int rowsDeleted = getContext().getContentResolver().delete(ShelfHelpContract.BookEntry.CONTENT_URI, null, null);
return true;
case R.id.action_discover:
/*TODO Here I want to open another Fragment and have it reflect
in the UI on my NavigationView and MainActivity
*/
return true;
}
return super.onOptionsItemSelected(item);
....
}

The following code takes care of replacing your Fragment when the user clicks on one of the navigation items
// Insert the fragment by replacing any existing fragment
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flContent, fragment).commit();
Besides replacing the fragment you will want to also update the title of your activity using something along the lines of:
((AppCompatActivity)getActivity()).getSupportActionBar().setTitle("Home");
And finally you must tell your NavigationView to highlight the right item using the setChecked(boolean) function. It should look something like this:
nvDrawer.getMenu().findItem(/*your item id*/).setChecked(true);
If you want to perform the same action when the user clicks on a menu item then make sure to add a new case to the switch block found in your onOptionsItemSelected(MenuItem item) and just call the same lines passing in the right Fragment

Related

Switching between activities and fragments in navigation drawer

I'm not an expert in Android, but really interested in fragments. Would be grateful for your help!
I've implemented a navigation drawer in my app. There is a base drawer activity and a number of fragments a user can switch between from the drawer menu. There is no problem if I want to move to another fragment, but it is working when I use an intent to start a new activity. If you look at my code below you'll see that I use two separate menus: one is for ActionBar icons (cart and search), where intents work perfectly and another one is for Nav drawer to jump between fragments. Is there any way to combine it in one? Basically, I need to move to Profile and Log out activities from nav drawer. Thank you for your advice in advance!
The screen is here
Java file
public class BaseDrawerActivity extends AppCompatActivity {
private DrawerLayout drawerLayout;
private NavigationView nvDrawer;
private ActionBarDrawerToggle actionBarDrawerToggle;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_base_drawer);
drawerLayout = findViewById(R.id.drawer);
actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, R.string.open, R.string.close);
drawerLayout.addDrawerListener(actionBarDrawerToggle);
actionBarDrawerToggle.syncState();
nvDrawer = findViewById(R.id.nvgView);
// Setup drawer view
setupDrawerContent(nvDrawer);
getSupportActionBar().setDisplayShowHomeEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
//Menu created for cart and search icons
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main_menu, menu);
return super.onCreateOptionsMenu(menu);
//return true;
}
//This method is designed only for cart and search icons
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if(actionBarDrawerToggle.onOptionsItemSelected(item)){
return true;
} else if (id == R.id.cart) {
Intent intent = new Intent(getApplicationContext(), CartActivity.class);
startActivity(intent);
} else if (id == R.id.search) {
Intent intent = new Intent(getApplicationContext(), SearchActivity.class);
startActivity(intent);
}
return super.onOptionsItemSelected(item);
}
//This method is to set up the drawer content/menu
private void setupDrawerContent(NavigationView navigationView) {
navigationView.setNavigationItemSelectedListener(
new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
selectDrawerItem(menuItem);
return true;
}
});
}
public void selectDrawerItem(MenuItem menuItem) {
// Here we create a new fragment and specify the fragment to show based on nav item clicked
Fragment fragment = null;
Class fragmentClass;
switch(menuItem.getItemId()) {
case R.id.nav_home:
fragmentClass = HomeFragment.class;
break;
case R.id.nav_cat:
fragmentClass = CatalogFragment.class;
break;
case R.id.nav_logout:
fragmentClass = CatalogFragment.class;
break;
case R.id.nav_login:
//what should I add here to be able to move to another activity (not a fragment). It doesn't work when I use intents
case R.id.nav_profile:
//need to move to another activity
default:
fragmentClass = HomeFragment.class;
}
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
// Insert the fragment by replacing any existing fragment
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flcontent, fragment).addToBackStack("back tag").commit();
// Highlight the selected item has been done by NavigationView
menuItem.setChecked(true);
// Set action bar title
setTitle(menuItem.getTitle());
// Close the navigation drawer
drawerLayout.closeDrawers();
}
}
Have you tried doing the same thing you did with the optionItems and preventing the code related to the fragment to be executed when starting an Activity:
public class BaseDrawerActivity extends AppCompatActivity {
private DrawerLayout drawerLayout;
private NavigationView nvDrawer;
private ActionBarDrawerToggle actionBarDrawerToggle;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_base_drawer);
drawerLayout = findViewById(R.id.drawer);
actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, R.string.open, R.string.close);
drawerLayout.addDrawerListener(actionBarDrawerToggle);
actionBarDrawerToggle.syncState();
nvDrawer = findViewById(R.id.nvgView);
// Setup drawer view
setupDrawerContent(nvDrawer);
getSupportActionBar().setDisplayShowHomeEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
//Menu created for cart and search icons
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main_menu, menu);
return super.onCreateOptionsMenu(menu);
//return true;
}
//This method is design only for cart and search icons
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if(actionBarDrawerToggle.onOptionsItemSelected(item)){
return true;
} else if (id == R.id.cart) {
Intent intent = new Intent(getApplicationContext(), CartActivity.class);
startActivity(intent);
} else if (id == R.id.search) {
Intent intent = new Intent(getApplicationContext(), SearchActivity.class);
startActivity(intent);
}
return super.onOptionsItemSelected(item);
}
//This method is to set up the drawer content/menu
private void setupDrawerContent(NavigationView navigationView) {
navigationView.setNavigationItemSelectedListener(
new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
selectDrawerItem(menuItem);
return true;
}
});
}
public void selectDrawerItem(MenuItem menuItem) {
// Here we create a new fragment and specify the fragment to show based on nav item clicked
Fragment fragment = null;
Class fragmentClass;
switch(menuItem.getItemId()) {
case R.id.nav_home:
fragmentClass = HomeFragment.class;
break;
case R.id.nav_cat:
fragmentClass = CatalogFragment.class;
break;
case R.id.nav_logout:
fragmentClass = CatalogFragment.class;
break;
case R.id.nav_login:
Intent intent = new Intent(getApplicationContext(), OtherActivity.class);
startActivity(intent);
break;
case R.id.nav_profile:
Intent intent = new Intent(getApplicationContext(), ProfileActivity.class);
startActivity(intent);
break;
default:
fragmentClass = HomeFragment.class;
}
//Code related to fragment should not execute when choosing to start an Activity
if(fragmentClass != null){
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
// Insert the fragment by replacing any existing fragment
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flcontent, fragment).addToBackStack("back tag").commit();
// Highlight the selected item has been done by NavigationView
}
menuItem.setChecked(true);
// Set action bar title
setTitle(menuItem.getTitle());
// Close the navigation drawer
drawerLayout.closeDrawers();
}
}

How to call a fragment every time you open the application?

I have a navigation drawer but the main activity has nothing, only the main page fragment has some thing, I want this fragment to be called every time the application opens. Anyone have any idea how to do this?
here is an example
As in code below, add this line in your code onNavigationItemSelected(nvDrawer.getMenu().getItem(0));
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
// ...From section above...
// Find our drawer view
nvDrawer = (NavigationView) findViewById(R.id.nvView);
// Setup drawer view
setupDrawerContent(nvDrawer);
selectDrawerItem(nvDrawer.getMenu().getItem(0));
}
private void setupDrawerContent(NavigationView navigationView) {
navigationView.setNavigationItemSelectedListener(
new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
selectDrawerItem(menuItem);
return true;
}
});
}
public void selectDrawerItem(MenuItem menuItem) {
// Create a new fragment and specify the fragment to show based on nav item clicked
Fragment fragment = null;
Class fragmentClass;
switch(menuItem.getItemId()) {
case R.id.nav_first_fragment:
fragmentClass = FirstFragment.class;
break;
case R.id.nav_second_fragment:
fragmentClass = SecondFragment.class;
break;
case R.id.nav_third_fragment:
fragmentClass = ThirdFragment.class;
break;
default:
fragmentClass = FirstFragment.class;
}
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
// Insert the fragment by replacing any existing fragment
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flContent, fragment).commit();
// Highlight the selected item has been done by NavigationView
menuItem.setChecked(true);
// Set action bar title
setTitle(menuItem.getTitle());
// Close the navigation drawer
mDrawer.closeDrawers();
}
}

Why setContentView doesn't disappear when changing fragment

I have a navigation drawer and when I click on one of the menus, I want the default content to disappear, but it just doesn't happen and when I click on a new menu it's still there.
This is really annoying, I've been trying to find solution the whole day and I'm going crazy now.
Please help me out, if you can. Thanks in advance!
I copy the whole code here. (p.s.: this is the first and last time I'm programming on Android, this is a nightmare...I just must do this now :/)
public class About extends AppCompatActivity {
private Toolbar toolbar;
private NavigationView navigationView;
private DrawerLayout drawerLayout;
ImageButton FAB;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_about);
FAB = (ImageButton) findViewById(R.id.imageButton);
FAB.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(About.this, SecondActivity.class);
startActivity(i);
//FAB click, call other thing...
}
});
navigationView = (NavigationView) findViewById(R.id.nav_view);
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.replace(R.id.content_frame, new ListViewFragment());
fragmentTransaction.commit();
setNavDrawer();
navigationView.setCheckedItem(R.id.nav_gallery);
}
private void setNavDrawer() {
// Initializing Toolbar and setting it as the actionbar
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
//Initializing NavigationView
//Setting Navigation View Item Selected Listener to handle the item click of the navigation menu
navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
// This method will trigger on item Click of navigation menu
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
//Checking if the item is in checked state or not, if not make it in checked state
if (menuItem.isChecked()) menuItem.setChecked(false);
else menuItem.setChecked(true);
//Closing drawer on item click
drawerLayout.closeDrawers();
//Check to see which item was being clicked and perform appropriate action
switch (menuItem.getItemId()) {
//Replacing the main content with ContentFragment Which is our Inbox View;
case R.id.nav_camera:
Toast.makeText(getApplicationContext(), "Clicked", Toast.LENGTH_SHORT).show();
ContentFragment fragment = new ContentFragment();
android.support.v4.app.FragmentTransaction f = getSupportFragmentManager().beginTransaction();
f.replace(R.id.content_frame, fragment);
f.commit();
return true;
// For rest of the options we just show a toast on click
case R.id.nav_gallery:
Toast.makeText(getApplicationContext(), "Whatever", Toast.LENGTH_SHORT).show();
UserFragment fragment2 = new UserFragment();
android.support.v4.app.FragmentTransaction f2 = getSupportFragmentManager().beginTransaction();
f2.replace(R.id.content_frame, fragment2);
f2.commit();
return true;
case R.id.nav_slideshow:
Toast.makeText(getApplicationContext(), "SOON", Toast.LENGTH_SHORT).show();
return true;
case R.id.nav_share:
Toast.makeText(getApplicationContext(), "SOON", Toast.LENGTH_SHORT).show();
return true;
default:
Toast.makeText(getApplicationContext(), "SOON", Toast.LENGTH_SHORT).show();
return true;
}
}
});
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle actionBarDrawerToggle = new ActionBarDrawerToggle(this,drawerLayout,toolbar,R.string.navigation_drawer_open, R.string.navigation_drawer_close){
#Override
public void onDrawerClosed(View drawerView) {
// Code here will be triggered once the drawer closes as we dont want anything to happen so we leave this blank
super.onDrawerClosed(drawerView);
}
#Override
public void onDrawerOpened(View drawerView) {
// Code here will be triggered once the drawer open as we dont want anything to happen so we leave this blank
super.onDrawerOpened(drawerView);
}
};
//Setting the actionbarToggle to drawer layout
drawerLayout.addDrawerListener(actionBarDrawerToggle);
//calling sync state is necessay or else your hamburger icon wont show up
actionBarDrawerToggle.syncState();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.about, menu);
return true;
}
#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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Use these code on menu click..
Fragment fragment = new ContentFragment();
FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.content_frame, fragment);
fragmentTransaction.remove(new CurrentFragment());
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
an also add these lines in xml
<FrameLayout
android:id="#+id/frame_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
Try this
Fragment fragment = new Fragment();
fragment.setRetainInstance(true);
fragment = new ContentFragment ();
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.content_frame, fragment)
.commit();

Google Navigation Drawer, handling backpress to set correct checked ite

Currently Used Google Navigation Drawer, having some problem when user backpress.
When user backpress, they didn't update menu Item
Example When I click the App. The sequence are A>B>C>B>C ,if I backpress I wanted to be C>B>A. How should I code this way out ?
My code
public class MainActivity extends AppCompatActivity {
private String appTitle;
private Toolbar toolbar;
private NavigationView navigationView;
private DrawerLayout drawerLayout;
private TextView toolbarTitle;
private Fragment fragment;
private FragmentManager fragmentManager;
private Title title;
private MenuItem menuItem2;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Actionbar
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
toolbarTitle = (TextView) toolbar.findViewById(R.id.toolbar_title);
toolbarTitle.setTextColor(Color.parseColor("#FFFFFF"));
setTitle("");
fragmentManager = getSupportFragmentManager();
fragment= new HomeFragment();
title = new Title(getApplicationContext());
fragmentManager.beginTransaction().replace(R.id.content_frame,fragment , title.getStrHome()).commit();
navigationView = (NavigationView) findViewById(R.id.navigation_view);
navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
menuItem2 = menuItem;
menuItem.setChecked(true);
drawerLayout.closeDrawers();
if (menuItem.getItemId() == R.id.nav_home) {
fragment = new HomeFragment();
appTitle = title.getStrHome();
} else if ((menuItem.getItemId() == R.id.nav_direction)) {
fragment = new DirectionFragment();
appTitle = title.getStrDirection();
} else if ((menuItem.getItemId() == R.id.nav_more)) {
fragment = new MoreFragment();
appTitle = title.getStrMore();
} else if((menuItem.getItemId()==R.id.nav_directory)){
fragment = new DirectoryFragment();
appTitle = title.getStrDirectory();
}
else {
Toast.makeText(getApplicationContext(), "Error", Toast.LENGTH_SHORT).show();
}
replaceFragment(fragment,appTitle);
return true;
}
});
drawerLayout = (DrawerLayout) findViewById(R.id.drawer);
ActionBarDrawerToggle actionBarDrawerToggle =
new ActionBarDrawerToggle
(this,drawerLayout,toolbar,R.string.drawer_open,R.string.drawer_close){
#Override
public void onDrawerClosed(View drawerView) {
super.onDrawerClosed(drawerView);
}
#Override
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
}
};
drawerLayout.setDrawerListener(actionBarDrawerToggle);
actionBarDrawerToggle.syncState();
}
public void onBackPressed() {
if(drawerLayout.isDrawerOpen(GravityCompat.START)){
drawerLayout.closeDrawer(GravityCompat.START);
}
else {
if (fragmentManager.getBackStackEntryCount() > 0 ){
fragmentManager.popBackStack();
toolbarTitle.setText(appTitle);
menuItem2.setChecked(true);
} else {
finish();
}
}
}
public void replaceFragment(Fragment fragment, String tag){
toolbarTitle.setText(tag);
FragmentTransaction ft = fragmentManager.beginTransaction().replace(R.id.content_frame, fragment, tag);
ft.addToBackStack(tag);
ft.commit();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
As stated on the official page on Android tasks and back stack you can see how you can accomplish your desired behaviour using the FLAG_ACTIVITY_CLEAR_TOP in your Intent flags. This picture demonstrates it very well.
Your regular back button proceeds as:
When you specify this flag, you get a behavior like you need
Edit:
The official documentation states:
FLAG_ACTIVITY_CLEAR_TOP
If the activity being started is already running in the current task, then instead of launching a new instance of that activity, all of the
other activities on top of it are destroyed
This means, there will be no duplicates of your different Activities, and you will have a clean Back Stack.
In your example A>B>C>B>C would not be possible. Instead it would be A>B>C, since B and C already exist in the stack, they will not be added, but replaced instead.
Study the Android Activity Launch Mode.
here is the clear Explanation available.
Just take a look.

How to select the first item in a navigation drawer and open a fragment on application start

I have created MainActivity with NavigationView. When Activity is opened I want to automatically select the first item in the navigation drawer and open Fragment under that item. I've searched a lot but didn't find any proper solutions.
What is the proper way to do this ?
Main Activity:
public class MainActivity extends AppCompatActivity implements Config {
private NavigationView navigationView;
private DrawerLayout drawerLayout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
toolbar.setTitleTextColor(getResources().getColor(R.color.colorIcons));
if (null != getSupportActionBar())
getSupportActionBar().setLogo(R.drawable.ic_blogger_white);
//Start PostListFragmentWebView
/*PostListFragmentWebView postListFragmentWebView = new PostListFragmentWebView();
getSupportFragmentManager().beginTransaction()
.replace(R.id.frame, postListFragmentWebView)
.commit();*/
//Initializing NavigationView
navigationView = (NavigationView) findViewById(R.id.navigationView);
//Setting Navigation View Item Selected Listener to handle the item click of the navigation menu
navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
//Checking if the item is in checked state or not, if not set it to checked state.
if (menuItem.isChecked()) menuItem.setChecked(false);
else menuItem.setChecked(true);
//Closing drawer on item click
drawerLayout.closeDrawers();
//Check to see which item was clicked and perform the appropriate action.
switch (menuItem.getItemId()) {
case R.id.posts:
PostListFragmentWebView postListFragment = new PostListFragmentWebView();
getSupportFragmentManager().beginTransaction()
.replace(R.id.frame, postListFragment)
.commit();
return true;
case R.id.pages:
PageListFragmentWebView pagetListFragment = new PageListFragmentWebView();
getSupportFragmentManager().beginTransaction()
.replace(R.id.frame, pagetListFragment)
.commit();
return true;
case R.id.blog:
BlogInfoFragmentWebView blogInfoFragment = new BlogInfoFragmentWebView();
getSupportFragmentManager().beginTransaction()
.replace(R.id.frame, blogInfoFragment)
.commit();
return true;
default:
Toast.makeText(getApplicationContext(), getResources().getString(R.string.drawer_error), Toast.LENGTH_SHORT).show();
return true;
}
}
});
// Initializing Drawer Layout and ActionBarToggle
drawerLayout = (DrawerLayout) findViewById(R.id.drawerLayout);
ActionBarDrawerToggle actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, toolbar, R.string.open_drawer, R.string.close_drawer) {
#Override
public void onDrawerClosed(View drawerView) {
// Code here will be triggered once the drawer closes as we don't want anything to happen so we leave this blank.
super.onDrawerClosed(drawerView);
}
#Override
public void onDrawerOpened(View drawerView) {
// Code here will be triggered once the drawer open as we dont want anything to happen so we leave this blank.
super.onDrawerOpened(drawerView);
}
};
//Setting the actionbarToggle to drawer layout
drawerLayout.setDrawerListener(actionBarDrawerToggle);
drawerLayout.getChildAt(0).setSelected(true);
//calling sync state is necessary or else your hamburger icon wont show up
actionBarDrawerToggle.syncState();
}
}
In onCreate(), following code will load the first item's fragment upon first start:
if (savedInstanceState == null) {
navigationView.getMenu().performIdentifierAction(R.id.posts, 0);
}
Thanks to calvinfly for this comment.
Add android:checked="true" to your first menu item.
And manually select one item, using
getSupportFragmentManager().beginTransaction().replace(R.id.frame, postListFragment).commit();
to open fragment.
Instead of normal listener ...
navView.setNavigationItemSelected(new Navigation.View.OnNavigationItemSelectedListener() {bla, bla, bla})
Create the listener as an Obj:
NavigationView.OnNavigationItemSelectedListener navViewListener;
navView.setNavigationItemSelectedListener(navViewListener = new NavigationView.OnNavigationItemSelectedListener() {bla, bla, bla})
...and use the Obj to trigger the listener event:
navViewListener.onNavigationItemSelected(navView.getMenu().getItem(0));
...where getItem(0) is the first menu item.
Use a method getItem(0).setChecked(true) or android:checked="true" at its menu item XML definition.
You could also use navigationView.setCheckedItem(R.id.default)(javadoc) after you setup your navigationview.
just add this code in onCreate method:
FragmentTransaction ftrans = getFragmentManager().beginTransaction();
ftrans.replace(R.id.container, <yourfragment>).commit();
Work for me !
This can be done even better while considering orientation and other configuration changes. We could select whatever nav drawer menuitem depending on whether we are coming from a previous state. Check: For the Navigation drawer wielding Activity:-
public static final String SELECTED_NAV_MENU_KEY = "selected_nav_menu_key";
// The selected grid position
private int mSelectedNavMenuIndex = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_demo);
...........................................................
navigationView.setNavigationItemSelectedListener(this);
if (savedInstanceState != null) {
// Recover assets
mSelectedNavMenuIndex = savedInstanceState.getInt(SELECTED_NAV_MENU_KEY);
// Recover menu as selected
MenuItem menuItem = navigationView.getMenu().getItem(mSelectedNavMenuIndex);
toggleNavMenuItemCheck(menuItem);
navigationView.getMenu().performIdentifierAction(menuItem.getItemId(), mSelectedNavMenuIndex);
return;
} else {
MenuItem menuItem = navigationView.getMenu().getItem(mSelectedNavMenuIndex);
toggleNavMenuItemCheck(menuItem);
navigationView.getMenu().performIdentifierAction(menuItem.getItemId(), mSelectedNavMenuIndex);
}
}
The toggle method that helps uncheck or check the menu item
private void toggleNavMenuItemCheck(MenuItem menuItem) {
if (menuItem.isChecked()){
menuItem.setChecked(false);
} else {
menuItem.setChecked(true);
}
}
This is how I save the state of the selected menu item. Check:-
#Override
public boolean onNavigationItemSelected(MenuItem item) {
int id = item.getItemId();
switch (id) {
case R.id.nav_explore:
showExploreFragment(null);
mSelectedNavMenuIndex = 0;
break;
case R.id.nav_orders:
mSelectedNavMenuIndex = 1;
break;
case R.id.nav_settings:
mSelectedNavMenuIndex = 2;
break;
default:
showExploreFragment(null);
mSelectedNavMenuIndex = 0;
}
drawer.closeDrawer(GravityCompat.START);
return true;
}
// Save any important data for recovery
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putInt(SELECTED_NAV_MENU_KEY, mSelectedNavMenuIndex);
}
NB: The line with code:
navigationView.getMenu().performIdentifierAction(menuItem.getItemId(), mSelectedNavMenuIndex);
Can be replaced by the code:
onNavigationItemSelected(menuItem);
in menu.xml remember to mention android:checkable="true" for single item and android:checkableBehavior="single" for a group of items.
<item
android:id="#+id/pos_item_help"
android:checkable="true"
android:title="Help" />
<group
android:id="#+id/group"
android:checkableBehavior="single">
<item
android:id="#+id/menu_nav_home"
android:icon="#drawable/ic_home_black_24dp"
android:title="#string/menu_nav_home" />
</group>
then inside NavigationItemSelectedListener use setCheckedItem(R.id.item_id_in_menu) to make it selected.
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.pos_item_pos:
navigationView.setCheckedItem(R.id.pos_item_pos);
break;
case R.id.pos_item_orders:
navigationView.setCheckedItem(R.id.pos_item_orders);
break;
default:
}
return true;
}
And you do not have to do the dirty task of managing the selected item anymore. navigationView manages it by self.
1.) To land to the HomeFragment initially, use this inside your onCreate() in MainActivity:
Fragment fragment = new HomeFragment();
// replacing the fragment
if (fragment != null) {
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.content_frame, fragment);
ft.commit();
}
2.) To set the item as selected in navigationDrawer set the item as checked in navigation_menu.xml
android:checked = "true"

Categories

Resources