AndroidStudio - Error in Fragments

Question

I'm trying to implement fragments by following a tutorial..below is my code..

Main activity

    package example.org.myfragment;

import android.os.Bundle;
import android.os.PersistableBundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemClickListener{

    private ActionBarDrawerToggle actionBarDrawerToggle;
    private DrawerLayout drawerLayout;
    private ListView navList;
    private FragmentTransaction fragmentTransaction;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        drawerLayout = (DrawerLayout) findViewById(R.id.drawerLayout);
        navList = (ListView) findViewById(R.id.navList);
        ArrayList<String> navArray = new ArrayList<String>();

        navArray.add("Notifications");
        navArray.add("My Profile");
        navArray.add("Home");
        navArray.add("Friends");
        navArray.add("Messages");
        navArray.add("Chat");
        navArray.add("Settings");
        navArray.add("Search");

        navList.setChoiceMode(ListView.CHOICE_MODE_SINGLE);

        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_activated_1,navArray);
        navList.setAdapter(adapter);
        navList.setOnItemClickListener(this);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        actionBarDrawerToggle = new ActionBarDrawerToggle(this,drawerLayout,R.string.opendrawer,R.string.closedrawer);
        drawerLayout.setDrawerListener(actionBarDrawerToggle);

        ActionBar actionBar = getSupportActionBar();
        actionBar.setDisplayShowHomeEnabled(true);
        actionBar.setDisplayHomeAsUpEnabled(true);
        FragmentManager fragmentManager = getSupportFragmentManager();
        fragmentTransaction = fragmentManager.beginTransaction();

        loadSelection(0);


        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });
    }

    private void loadSelection(int i){
        navList.setItemChecked(i, true);

        switch (i){
            case 0:
                Notifications notifications = new Notifications();
                fragmentTransaction.replace(R.id.fragmentHolder,notifications);
                fragmentTransaction.commit();
                break;
            case 1:
                MyProfile myProfile = new MyProfile();
                fragmentTransaction.replace(R.id.fragmentHolder,myProfile);
                fragmentTransaction.commit();
                break;
            case 2:
                Home home = new Home();
                fragmentTransaction.replace(R.id.fragmentHolder,home);
                fragmentTransaction.commit();
                break;
            case 3:
                Friends friends = new Friends();
                fragmentTransaction.replace(R.id.fragmentHolder,friends);
                fragmentTransaction.commit();
                break;
            case 4:
                Messages messages = new Messages();
                fragmentTransaction.replace(R.id.fragmentHolder,messages);
                fragmentTransaction.commit();
                break;
            case 5:

                break;
            case 6:

                break;
            case 7:

                break;
        }

    }

    @Override
    public void onPostCreate(Bundle savedInstanceState, PersistableBundle persistentState) {
        super.onPostCreate(savedInstanceState, persistentState);
        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.menu_main, 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;
        }else if (id==android.R.id.home){
            if(drawerLayout.isDrawerOpen(navList)){
                drawerLayout.closeDrawer(navList);
            }else{
                drawerLayout.openDrawer(navList);
            }
        }

        return super.onOptionsItemSelected(item);
    }

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

        drawerLayout.closeDrawer(navList);
    }
}

activity_main.xml

<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/drawerLayout">

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/fragmentHolder">

    </FrameLayout>

    <ListView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="#dedede"
        android:layout_gravity="start"
        android:id="@+id/navList">
    </ListView>

</android.support.v4.widget.DrawerLayout>

fragment_notifications.xml

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="example.org.myfragment.Notifications">

    <!-- TODO: Update blank fragment layout -->
    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="@string/Notifications"
        android:gravity="center|top"/>


</FrameLayout>

strings.xml

<resources>
    <string name="app_name">MyFragment</string>
    <string name="action_settings">Settings</string>
    <string name="opendrawer">Open</string>
    <string name="closedrawer">Close</string>

    <!-- TODO: Remove or change this placeholder text -->
    <string name="Notifications">Notifications</string>

    <!-- TODO: Remove or change this placeholder text -->
    <string name="MyProfile">MyProfile</string>

    <!-- TODO: Remove or change this placeholder text -->
    <string name="Home">Home</string>

    <!-- TODO: Remove or change this placeholder text -->
    <string name="Friends">Friends</string>

    <!-- TODO: Remove or change this placeholder text -->
    <string name="Messages">Messages</string>

</resources>

logcat:

12-19 00:33:20.054 2625-2625/? I/art: Not late-enabling -Xcheck:jni (already on)
12-19 00:33:20.054 2625-2625/? I/art: Late-enabling JIT
12-19 00:33:20.058 2625-2625/? I/art: JIT created with code_cache_capacity=2MB compile_threshold=1000
12-19 00:33:20.151 2625-2625/example.org.myfragment W/System: ClassLoader referenced unknown path: /data/app/example.org.myfragment-2/lib/x86
12-19 00:33:20.362 2625-2651/example.org.myfragment D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true
12-19 00:33:20.443 2625-2651/example.org.myfragment I/OpenGLRenderer: Initialized EGL, version 1.4
12-19 00:33:20.487 2625-2651/example.org.myfragment W/EGL_emulation: eglSurfaceAttrib not implemented
12-19 00:33:20.487 2625-2651/example.org.myfragment W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0xabf3bda0, error=EGL_SUCCESS
12-19 00:33:21.221 2625-2625/example.org.myfragment I/Choreographer: Skipped 42 frames!  The application may be doing too much work on its main thread.
12-19 00:33:33.712 2625-2625/example.org.myfragment D/AndroidRuntime: Shutting down VM
12-19 00:33:33.712 2625-2625/example.org.myfragment E/AndroidRuntime: FATAL EXCEPTION: main
                                                                      Process: example.org.myfragment, PID: 2625
                                                                      java.lang.IllegalStateException: commit already called
                                                                          at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:621)
                                                                          at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:613)
                                                                          at example.org.myfragment.MainActivity.loadSelection(MainActivity.java:89)
                                                                          at example.org.myfragment.MainActivity.onItemClick(MainActivity.java:155)
                                                                          at android.widget.AdapterView.performItemClick(AdapterView.java:310)
                                                                          at android.widget.AbsListView.performItemClick(AbsListView.java:1145)
                                                                          at android.widget.AbsListView$PerformClick.run(AbsListView.java:3042)
                                                                          at android.widget.AbsListView$3.run(AbsListView.java:3879)
                                                                          at android.os.Handler.handleCallback(Handler.java:739)
                                                                          at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                          at android.os.Looper.loop(Looper.java:148)
                                                                          at android.app.ActivityThread.main(ActivityThread.java:5417)
                                                                          at java.lang.reflect.Method.invoke(Native Method)
                                                                          at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
                                                                          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
12-19 00:33:36.026 2625-2625/? I/Process: Sending signal. PID: 2625 SIG: 9

App crashes when I click on any fragment.. And the first fragment "Notifications" doesn't show up at all..

post your logcat @Spider – curiousMind Dec 19 '15 at 05:22 — curiousMind, Dec 19 '15 at 05:22
Will we have to find your error in your code? – Androider Dec 19 '15 at 05:29 — Androider, Dec 19 '15 at 05:29
Updated in the question..@Android @Androider – Spider Dec 19 '15 at 05:35 — Spider, Dec 19 '15 at 05:35

curiousMind · Accepted Answer · 2015-12-19T06:13:16.433

try to do something like this ::

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemClickListener{

private ActionBarDrawerToggle actionBarDrawerToggle;
private DrawerLayout drawerLayout;
private ListView navList;
private FragmentTransaction fragmentTransaction;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    drawerLayout = (DrawerLayout) findViewById(R.id.drawerLayout);
    navList = (ListView) findViewById(R.id.navList);
    ArrayList<String> navArray = new ArrayList<String>();

    navArray.add("Notifications");
    navArray.add("My Profile");
    navArray.add("Home");
    navArray.add("Friends");
    navArray.add("Messages");
    navArray.add("Chat");
    navArray.add("Settings");
    navArray.add("Search");

    navList.setChoiceMode(ListView.CHOICE_MODE_SINGLE);

    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_activated_1,navArray);
    navList.setAdapter(adapter);
    navList.setOnItemClickListener(this);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    actionBarDrawerToggle = new ActionBarDrawerToggle(this,drawerLayout,R.string.opendrawer,R.string.closedrawer);
    drawerLayout.setDrawerListener(actionBarDrawerToggle);

    ActionBar actionBar = getSupportActionBar();
    actionBar.setDisplayShowHomeEnabled(true);
    actionBar.setDisplayHomeAsUpEnabled(true);
    FragmentManager fragmentManager = getSupportFragmentManager();
    fragmentTransaction = fragmentManager.beginTransaction();

   // loadSelection(0);


    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });
}

private void loadSelection(int i){
    navList.setItemChecked(i, true);

    switch (i){
        case 0:
            Notifications notifications = new Notifications();
            fragmentTransaction.replace(R.id.fragmentHolder,notifications).commit();

            break;
        case 1:
            MyProfile myProfile = new MyProfile();
            fragmentTransaction.replace(R.id.fragmentHolder,myProfile).commit();

            break;
        case 2:
            Home home = new Home();
            fragmentTransaction.replace(R.id.fragmentHolder,home).commit();

            break;
        case 3:
            Friends friends = new Friends();
            fragmentTransaction.replace(R.id.fragmentHolder,friends).commit();

            break;
        case 4:
            Messages messages = new Messages();
            fragmentTransaction.replace(R.id.fragmentHolder,messages).commit();

            break;
        case 5:

            break;
        case 6:

            break;
        case 7:

            break;
    }

}

@Override
public void onPostCreate(Bundle savedInstanceState, PersistableBundle persistentState) {
    super.onPostCreate(savedInstanceState, persistentState);
    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.menu_main, 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;
    }else if (id==android.R.id.home){
        if(drawerLayout.isDrawerOpen(navList)){
            drawerLayout.closeDrawer(navList);
        }else{
            drawerLayout.openDrawer(navList);
        }
    }

    return super.onOptionsItemSelected(item);
}

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

    drawerLayout.closeDrawer(navList);
}

}

@android, @Spider that is good if problem is resolved. but i have one doubt in your code you are creating `FragmentTransaction` instance only once and using same one so every time you call `loadSelection` method it will use old instance of `FragmentTransaction` so after repetedaly replacing fragment will cause the same error which you posted AFAIK. No offence with vote or accepted point.. just trying to help and asking for knowledge — user1140237, Dec 19 '15 at 06:53
@Spider np with upvote or points fine happy if the issue is resolved but check above comment .. :) — user1140237, Dec 19 '15 at 06:54

score 1 · Answer 2 · answered Dec 19 '15 at 05:59

Do not declare FragmentTransaction object globally. You have to create new object of FragmentTransaction every time, when you click on list item.

So define FragmentTransaction inside your loadSelection method after switch case.

private void loadSelection(int i){
        Fragment fragment;

        switch (i){
            case 0:
                fragment = new Notifications();
                break;
            case 1:
                fragment = new MyProfile();
                break;
            ......
        }

        if(fragment != null) {
            FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
            ft.replace(R.id.fragmentHolder , fragment);
            ft.commit();
        }
}

score 1 · Answer 3 · answered Dec 19 '15 at 06:14

You need to take New FragmentTransaction every time you change fragment

private void loadSelection(int i){
        navList.setItemChecked(i, true);

        switch (i){
            case 0:

                Notifications notifications = new Notifications();
                getSupportFragmentManager().beginTransaction().replace(R.id.fragmentHolder,notifications).commit();

                break;
            case 1:

                MyProfile myProfile = new MyProfile();
                getSupportFragmentManager().beginTransaction().replace(R.id.fragmentHolder,myProfile).commit();

                break;
            case 2:

                Home home = new Home();
                getSupportFragmentManager().beginTransaction().replace(R.id.fragmentHolder,home).commit();

                break;
            case 3:

                Friends friends = new Friends();
                getSupportFragmentManager().beginTransaction().replace(R.id.fragmentHolder,friends).commit();

                break;
            case 4:
                Messages messages = new Messages();
                getSupportFragmentManager().beginTransaction().replace(R.id.fragmentHolder,messages).commit();

                break;
            case 5:

                break;
            case 6:

                break;
            case 7:

                break;
        }

    }

AndroidStudio - Error in Fragments

3 Answers3