Develop Reference

NoClassDefFoundError error in Android Slider

I am creating an app with a slider and it was working fine and then I added another view and implemented an OnClickListener() for the newly added Views after that I am getting the following error when I open my app
Process: com.spintum.preexam, PID: 31905
java.lang.NoClassDefFoundError: com.spintum.preexam.CustomList$DrawerItemHolder
at com.spintum.preexam.CustomList.getView(CustomList.java:38)
at android.widget.AbsListView.obtainView(AbsListView.java:2338)
at android.widget.ListView.makeAndAddView(ListView.java:1812)
at android.widget.ListView.fillDown(ListView.java:698)
at android.widget.ListView.fillFromTop(ListView.java:759)
at android.widget.ListView.layoutChildren(ListView.java:1645)
at android.widget.AbsListView.onLayout(AbsListView.java:2149)
at android.view.View.layout(View.java:15125)
at android.view.ViewGroup.layout(ViewGroup.java:4862)
at android.support.v4.widget.DrawerLayout.onLayout(DrawerLayout.java:931)
at android.view.View.layout(View.java:15125)
at android.view.ViewGroup.layout(ViewGroup.java:4862)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:515)
at android.widget.FrameLayout.onLayout(FrameLayout.java:450)
at android.view.View.layout(View.java:15125)
at android.view.ViewGroup.layout(ViewGroup.java:4862)
at com.android.internal.widget.ActionBarOverlayLayout.onLayout(ActionBarOverlayLayout.java:374)
at android.view.View.layout(View.java:15125)
at android.view.ViewGroup.layout(ViewGroup.java:4862)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:515)
at android.widget.FrameLayout.onLayout(FrameLayout.java:450)
at android.view.View.layout(View.java:15125)
at android.view.ViewGroup.layout(ViewGroup.java:4862)
at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2317)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2023)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1189)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6223)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:788)
at android.view.Choreographer.doCallbacks(Choreographer.java:591)
at android.view.Choreographer.doFrame(Choreographer.java:560)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:774)
at android.os.Handler.handleCallback(Handler.java:808)
at android.os.Handler.dispatchMessage(Handler.java:103)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:5292)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:824)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:640)
at dalvik.system.NativeStart.main(Native Method)
The class in which the logcat shows the NoClassDefFound error is as follows
public class CustomList extends ArrayAdapter<DrawerItem> {
Context context;
List<DrawerItem> drawerItemList;
int layoutResID;
public CustomList(Context context, int layoutResourceID,
List<DrawerItem> listItems) {
super(context, layoutResourceID, listItems);
this.context = context;
this.drawerItemList = listItems;
this.layoutResID = layoutResourceID;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
DrawerItemHolder drawerHolder;
View view = convertView;
if (view == null) {
LayoutInflater inflater = ((Activity) context).getLayoutInflater();
drawerHolder = new DrawerItemHolder();
view = inflater.inflate(layoutResID, parent, false);
drawerHolder.ItemName = (TextView) view.findViewById(R.id.drawer_item_text);
drawerHolder.icon = (ImageView) view.findViewById(R.id.drawer_item_icon);
view.setTag(drawerHolder);
} else {
drawerHolder = (DrawerItemHolder) view.getTag();
}
DrawerItem dItem = (DrawerItem) this.drawerItemList.get(position);
drawerHolder.icon.setImageDrawable(view.getResources().getDrawable(
dItem.getImgResID()));
drawerHolder.ItemName.setText(dItem.getItemName());
return view;
}
private static class DrawerItemHolder {
TextView ItemName;
ImageView icon;
}
}
The error is shown in drawerHolder = new DrawerItemHolder(); line.
I have not made any changes to this class so I am thinking the problem might be caused by the extra views that I added in my original activity that acts as a fragment container. The activity's code is as follows
public class Home extends Activity {
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;
private CharSequence mDrawerTitle;
private CharSequence mTitle;
private String[] mPlanetTitles;
private static int pos;
List<DrawerItem> dataList = new ArrayList<DrawerItem>();
View statistics,test,syllabus,share;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
this.getActionBar().setBackgroundDrawable(
getResources().getDrawable(R.color.background));
this.overridePendingTransition(R.layout.fade_in, R.layout.fade_out);
mTitle = mDrawerTitle = getTitle();
mPlanetTitles = getResources().getStringArray(R.array.planets_array);
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
mDrawerList = (ListView) findViewById(R.id.left_drawer);
statistics=findViewById(R.id.statistics_container);
test=findViewById(R.id.test_container);
syllabus=findViewById(R.id.syllabus_container);
share=findViewById(R.id.share_container);
statistics.setOnClickListener(mBottomDrawerListener);
syllabus.setOnClickListener(mBottomDrawerListener);
test.setOnClickListener(mBottomDrawerListener);
share.setOnClickListener(mBottomDrawerListener);
TextView image=(TextView)findViewById(R.id.statistics_image);
TextView text=(TextView)findViewById(R.id.statistics);
image.setTextColor(Color.parseColor("#03a9f4"));
text.setTextColor(Color.parseColor("#03a9f4"));
// set a custom shadow that overlays the main content when the drawer opens
mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow,GravityCompat.START);
int width = getResources().getDisplayMetrics().widthPixels;
DrawerLayout.LayoutParams params = (android.support.v4.widget.DrawerLayout.LayoutParams) mDrawerList.getLayoutParams();
//params.width = (width * 75) / 100;
mDrawerList.setLayoutParams(params);
// set up the drawer's list view with items and click listener
/*
* mDrawerList.setAdapter(new ArrayAdapter<String>(this,
* R.layout.list_item, mPlanetTitles));
*/
dataList.add(new DrawerItem("Home", R.drawable.home));
dataList.add(new DrawerItem("Intelligence Questionnaire",
R.drawable.bulb));
dataList.add(new DrawerItem("Change Country", R.drawable.location));
dataList.add(new DrawerItem("LeaderBoard", R.drawable.cup));
dataList.add(new DrawerItem("How to play", R.drawable.help));
dataList.add(new DrawerItem("Exam Tips", R.drawable.tip));
mDrawerList.setAdapter(new CustomList(Home.this, R.layout.list_item,dataList));
mDrawerList.setOnItemClickListener(new DrawerItemClickListener());
// enable ActionBar app icon to behave as action to toggle nav drawer
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setHomeButtonEnabled(true);
// ActionBarDrawerToggle ties together the the proper interactions
// between the sliding drawer and the action bar app icon
mDrawerToggle = new ActionBarDrawerToggle(this, /* host Activity */ mDrawerLayout, /* DrawerLayout object */R.drawable.ic_drawer, /* nav drawer image to replace 'Up' caret */R.string.drawer_open, /* "open drawer" description for accessibility */
R.string.drawer_close /* "close drawer" description for accessibility */) {
public void onDrawerClosed(View view) {
getActionBar().setTitle(mTitle);
invalidateOptionsMenu(); // creates call to
// onPrepareOptionsMenu()
}
public void onDrawerOpened(View drawerView) {
getActionBar().setTitle(mDrawerTitle);
invalidateOptionsMenu(); // creates call to
// onPrepareOptionsMenu()
}
};
mDrawerLayout.setDrawerListener(mDrawerToggle);
if (savedInstanceState == null) {
selectItem(0);
}
Typeface iconfont=FontManager.getTypeface(getApplicationContext(),FontManager.FONTAWESOME);
FontManager.markAsIconContainer(findViewById(R.id.btm_nav_bar),iconfont);
}
public View.OnClickListener mBottomDrawerListener=new View.OnClickListener() {
#Override
public void onClick(View v) {
FragmentManager fragmentManager=getFragmentManager();
setBlackText(v);
TextView image,text;
switch (v.getId()){
case R.id.statistics_container:
fragmentManager.beginTransaction().replace(R.id.content_frame,new HomePage()).commit();
image=(TextView)v.findViewById(R.id.statistics_image);
text=(TextView)v.findViewById(R.id.statistics);
image.setTextColor(Color.parseColor("#03a9f4"));
text.setTextColor(Color.parseColor("#03a9f4"));
break;
case R.id.syllabus_container:
image=(TextView)v.findViewById(R.id.syllabus_image);
text=(TextView)v.findViewById(R.id.syllabus_btm);
image.setTextColor(Color.parseColor("#03a9f4"));
text.setTextColor(Color.parseColor("#03a9f4"));
break;
case R.id.test_container:
image=(TextView)v.findViewById(R.id.test_image);
text=(TextView)v.findViewById(R.id.Tests);
image.setTextColor(Color.parseColor("#03a9f4"));
text.setTextColor(Color.parseColor("#03a9f4"));
break;
case R.id.share_container:
image=(TextView)v.findViewById(R.id.share_image);
text=(TextView)v.findViewById(R.id.share_btm);
image.setTextColor(Color.parseColor("#03a9f4"));
text.setTextColor(Color.parseColor("#03a9f4"));
break;
}
}
};
public void setBlackText(View v){
TextView img[]=new TextView[4];
TextView t1,t2,t3,t4;
img[0]=(TextView)findViewById(R.id.statistics_image);
t4=(TextView)findViewById(R.id.statistics);
img[1]=(TextView)findViewById(R.id.test_image);
t1=(TextView)findViewById(R.id.Tests);
img[2]=(TextView)findViewById(R.id.syllabus_image);
t2=(TextView)findViewById(R.id.syllabus_btm);
img[3]=(TextView)findViewById(R.id.share_image);
t3=(TextView)findViewById(R.id.share_btm);
for(TextView singleTextView:img){
singleTextView.setTextColor(Color.parseColor("#000000"));
}
t1.setTextColor(Color.parseColor("#000000"));
t2.setTextColor(Color.parseColor("#000000"));
t3.setTextColor(Color.parseColor("#000000"));
t4.setTextColor(Color.parseColor("#000000"));
}
/*
* #Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater
* inflater = getMenuInflater(); inflater.inflate(R.menu.activity_main,
* menu); return super.onCreateOptionsMenu(menu); }
*
* Called whenever we call invalidateOptionsMenu()
*
* #Override public boolean onPrepareOptionsMenu(Menu menu) { // If the nav
* drawer is open, hide action items related to the content view boolean
* drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);
* //menu.findItem(R.id.action_websearch).setVisible(!drawerOpen); return
* super.onPrepareOptionsMenu(menu); }
*/
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// The action bar home/up action should open or close the drawer.
// ActionBarDrawerToggle will take care of this.
if (mDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
// Handle action buttons
switch (item.getItemId()) {
case 1:
// create intent to perform web search for this planet
Intent intent = new Intent(Intent.ACTION_WEB_SEARCH);
intent.putExtra(SearchManager.QUERY, getActionBar().getTitle());
// catch event that there's no activity to handle intent
if (intent.resolveActivity(getPackageManager()) != null) {
startActivity(intent);
} else {
Toast.makeText(this, R.string.app_not_available,
Toast.LENGTH_LONG).show();
}
return true;
default:
return super.onOptionsItemSelected(item);
}
}
/* The click listner for ListView in the navigation drawer */
private class DrawerItemClickListener implements
ListView.OnItemClickListener {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
selectItem(position);
}
}
private void selectItem(int position) {
// update the main content by replacing fragments
/*
* Fragment fragment = new HomePage(); Bundle args = new Bundle();
* args.putInt(PlanetFragment.ARG_PLANET_NUMBER, position);
* fragment.setArguments(args);
*/
pos = position;
FragmentManager fragmentManager = getFragmentManager();
switch (pos) {
case 0:
fragmentManager.beginTransaction().replace(R.id.content_frame, new Fragment_Statistics()).commit();
break;
case 1:
break;
case 2:
fragmentManager.beginTransaction().replace(R.id.content_frame, new Country()).commit();
case 3:break;
case 4:break;
case 5:break;
}
// update selected item and title, then close the drawer
mDrawerList.setItemChecked(position, true);
setTitle(mPlanetTitles[position]);
mDrawerLayout.closeDrawer(mDrawerList);
}
#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);
}
}
The DrawerItem class used in the Home activity is given below
public class DrawerItem {
String ItemName;
int imgResID;
public DrawerItem(String itemName, int imgResID) {
super();
ItemName = itemName;
this.imgResID = imgResID;
}
public String getItemName() {
return ItemName;
}
public void setItemName(String itemName) {
ItemName = itemName;
}
public int getImgResID() {
return imgResID;
}
public void setImgResID(int imgResID) {
this.imgResID = imgResID;
}}
Can someone see where I am going wrong? Thanks in advance..

DrawerItemHolder class should be public, or at least it should not be private.

Android - Error in creating Youtube fragment

I'm creating android fragment that can play youtube video by using Youtube API Player. In MainActivity class, I'm getting error that
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 VideoFragment();
break;
case 2:
fragment = new ThirdFragment();
break;
default:
break;
}
Type mismatch: cannot convert from VideoFragment to Fragment
However, when I switch to new code:
private void displayView(int position) {
// update the main content by replacing fragments
VideoFragment fragment =null;
switch (position) {
case 0:
fragment = new HomeFragment();
break;
case 1:
fragment = new VideoFragment();
break;
case 2:
fragment = new ThirdFragment();
break;
default:
break;
}
This error occur
Type mismatch: cannot convert from ThirdFragment to VideoFragment
MainActivity full code:
public class MainActivity extends Activity implements NavigationDrawerFragment.NavigationDrawerCallbacks {
final Context context = this;
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[] navMenuTitles;
private TypedArray navMenuIcons;
private ArrayList<NavDrawerItem> navDrawerItems;
private NavDrawerListAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setHomeButtonEnabled(true);
mTitle = mDrawerTitle = getTitle();
// load slide menu items
navMenuTitles = getResources().getStringArray(R.array.nav_drawer_items);
// 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 arrayonCreateOptionsMenu
// Home
navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1)));
// Video
navDrawerItems.add(new NavDrawerItem(navMenuTitles[1], navMenuIcons.getResourceId(1, -1)));
// Photos
navDrawerItems.add(new NavDrawerItem(navMenuTitles[2], navMenuIcons.getResourceId(2, -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
) {
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) {
// on first time display view for first nav item
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;
}
// Handle action bar actions click
switch (item.getItemId()) {
case R.id.action_settings:
final Dialog dialog = new Dialog(context);
dialog.setContentView(R.layout.custom);
dialog.setTitle("Event Story");
// set the custom dialog components - text, image and button
TextView text = (TextView) dialog.findViewById(R.id.text);
text.setText("Develop and maintained by W.I.N Sdn. Bhd");
Button dialogButton = (Button) dialog.findViewById(R.id.dialogButtonOK);
// if button is clicked, close the custom dialog
dialogButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
}
});
dialog.show();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
/* *
* 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_settings).setVisible(!drawerOpen);
return super.onPrepareOptionsMenu(menu);
}
/**
* Diplaying fragment view for selected nav drawer list item
* */
public void onNavigationDrawerItemSelected(int position) {
// TODO Auto-generated method stub
}
private void displayView(int position) {
// update the main content by replacing fragments
VideoFragment fragment =null;
switch (position) {
case 0:
fragment = new HomeFragment();
break;
case 1:
fragment = new VideoFragment();
break;
case 2:
fragment = new ThirdFragment();
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);
}
#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);
}
public void openBrowser(View view){
//Get url from tag
String url = (String)view.getTag();
Intent intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
intent.addCategory(Intent.CATEGORY_BROWSABLE);
//pass the url to intent data
intent.setData(Uri.parse(url));
startActivity(intent);
}}
VideoFragment.java
public class VideoFragment extends YouTubeFailureRecoveryActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.videoview_fragment);
YouTubePlayerFragment youTubePlayerFragment =
(YouTubePlayerFragment) getFragmentManager().findFragmentById(R.id.VideoView);
youTubePlayerFragment.initialize(DeveloperKey.DEVELOPER_KEY, this);
}
#Override
public void onInitializationSuccess(YouTubePlayer.Provider provider, YouTubePlayer player,
boolean wasRestored) {
if (!wasRestored) {
player.cueVideo("https://www.youtube.com/watch?v=pzWfjOaAbcE");
}
}
#Override
protected YouTubePlayer.Provider getYouTubePlayerProvider() {
return (YouTubePlayerFragment) getFragmentManager().findFragmentById(R.id.VideoView);
}
}

Fragments and Activities are not the same thing. Activity does not inherit from fragment look at this question.
In the case VideoFragment inherited Fragment, and assuming HomeFragment and ThirdFragment also inherit from Fragment, you first approach should work.

Opening Activity from Navigation Drawer

Every time I open my Activity from Navigation Drawer, a blank screen appears. I am trying to open a fragment from my Navigation:
public class MainActivity extends ActionBarActivity {
private ListView mDrawerList;
private DrawerLayout mDrawerLayout;
private ArrayAdapter<String> mAdapter;
private ActionBarDrawerToggle mDrawerToggle;
private String mActivityTitle;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mDrawerList = (ListView)findViewById(R.id.navList);mDrawerLayout = (DrawerLayout)findViewById(R.id.drawer_layout);
mActivityTitle = getTitle().toString();
addDrawerItems();
setupDrawer();
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
}
private void addDrawerItems() {
String[] osArray = {"Math", "Physics", "Chemistry"};
mAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, osArray);
mDrawerList.setAdapter(mAdapter);
mDrawerList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
switch(position) {
case 0:
Intent a = new Intent(MainActivity.this, MathActivity.class);
startActivity(a);
break;
case 1:
Intent b = new Intent(MainActivity.this, PhysicsActivity.class);
startActivity(b);
break;
case 2:
Intent c = new Intent(MainActivity.this, ChemistryActivity.class );
startActivity(c);
break;
default:
}
}
});
}
private void setupDrawer() {
mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout, R.string.drawer_open, R.string.drawer_close) {
/** Called when a drawer has settled in a completely open state. */
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
getSupportActionBar().setTitle("Navigation!");
invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
}
/** Called when a drawer has settled in a completely closed state. */
public void onDrawerClosed(View view) {
super.onDrawerClosed(view);
getSupportActionBar().setTitle(mActivityTitle);
invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
}
};
mDrawerToggle.setDrawerIndicatorEnabled(true);
mDrawerLayout.setDrawerListener(mDrawerToggle);
}
#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);
mDrawerToggle.onConfigurationChanged(newConfig);
}
#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;
}
// Activate the navigation drawer toggle
if (mDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
To open Activity like this:
public class MathActivity extends Activity{
protected void onCreate(Bundle bundle) {
setContentView(R.layout.math_fragment_activity);
super.onCreate(bundle);
}
}
Every time I do so, a blank screen appears. Why is this happening and can anyone help me solve this problem?
UPDATE:
Here is my layout file:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="#+id/listViewAnimals"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:dividerHeight="0.1dp"
android:divider="#0000CC"/> </RelativeLayout>

Try switching your setContentiew to be after the super.onCreate call.

Navigation Drawer not opening when I follow tutorial code

I am new to android programming. I was trying to build navigation drawer and I followed this tutorial. The navigation drawer is not getting created and I am getting errors and the app is also terminating.
Below is my code
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;
private CharSequence mDrawerTitle;
// used to store app title
private CharSequence mTitle;
// slide menu items
private String[] navMenuTitles;
private TypedArray navMenuIcons;
private ArrayList<NavDrawerItem> navDrawerItems;
private NavDrawerListAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_options);
mTitle = mDrawerTitle = getTitle();
// load slide menu items
navMenuTitles = getResources().getStringArray(R.array.nav_drawer_items);
// 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)));
// Find People
navDrawerItems.add(new NavDrawerItem(navMenuTitles[1], navMenuIcons.getResourceId(1, -1)));
// Photos
navDrawerItems.add(new NavDrawerItem(navMenuTitles[2], navMenuIcons.getResourceId(2, -1)));
// Communities, Will add a counter here
navDrawerItems.add(new NavDrawerItem(navMenuTitles[3], navMenuIcons.getResourceId(3, -1)));
// Pages
navDrawerItems.add(new NavDrawerItem(navMenuTitles[4], navMenuIcons.getResourceId(4, -1)));
// Recycle the typed array
navMenuIcons.recycle();
// 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,
R.string.app_name){
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) {
// on first time display view for first nav item
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 onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
Toast.makeText(getApplicationContext(),
"Logging Out!", Toast.LENGTH_LONG).show();
Intent i = new Intent(OptionsActivity.this, LoginActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
//i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(i);
// return true;
OptionsActivity.this.finish();
}
if (mDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
// Handle action bar actions click
switch (item.getItemId()) {
case R.id.action_settings:
return true;
default:
return super.onOptionsItemSelected(item);
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.options, menu);
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_settings).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 EventFragment();
break;
case 2:
fragment = new EventsCalendarFragment();
break;
case 3:
fragment = new CmritForumFragment();
break;
case 4:
fragment = new ChangePasswordFragment();
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);
}
}
This is the fragment.xml file
` <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/txtLabel"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:textSize="16sp"
android:text="#string/home_view"/>
<ImageView android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#id/txtLabel"
android:src="#drawable/ic_home"
android:layout_centerHorizontal="true"
android:layout_marginTop="10dp"
android:contentDescription="#string/desc"/>
</RelativeLayout> `

Try changing if you are using this in your code
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setHomeButtonEnabled(true);
to
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
Or simply try changing ActionBarActivity to Activity.
You are not setting the click listener...please do this also
mDrawerList.setOnItemClickListener(new SlideMenuClickListener());

you are getting and null from this line:
getActionBar().setDisplayHomeAsUpEnabled(true);
you need to check why your action bar is null.
can you post your class itself?
does your class extends ActionBarActivity?

ActionBarDrawerToggle's constructor
public ActionBarDrawerToggle (Activity activity, DrawerLayout drawerLayout, int drawerImageRes, int openDrawerContentDescRes, int closeDrawerContentDescRes)
Click [here]
https://developer.android.com/reference/android/support/v4/app/ActionBarDrawerToggle.html#ActionBarDrawerToggle

How to start a new activity from item click in NavDrawer

I'm a novice. I was just wondering how to start a new (pre-defined) activity from clicking one of the option items inside a navigation drawer? I have just completed a tutorial on how to make the NavDrawer. Here is what I have so far in my main activity (it's called IntroActivity)
IntroActivity.java:
public class IntroActivity extends Activity {
private String[] drawerListViewItems;
private ListView drawerListView;
private DrawerLayout drawerLayout;
private ActionBarDrawerToggle actionBarDrawerToggle;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_intro);
//Retrieve List items from strings.xml
drawerListViewItems = getResources().getStringArray(R.array.list_items);
//Retrieve ListView defined in intro_activity.xml
drawerListView = (ListView) findViewById(R.id.left_drawer);
//Set the adapter for the list view
drawerListView.setAdapter(new ArrayAdapter<String>(this, R.layout.drawer_listview_item, drawerListViewItems));
//App Icon
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
actionBarDrawerToggle = new ActionBarDrawerToggle(
this, /* Host Activity */
drawerLayout, /* DrawerLayout object */
R.drawable.ic_drawer, /* Image to replace "up" image*/
R.string.drawer_open, /* Open drawer description*/
R.string.drawer_close /* Close drawer description*/
);
//Set actionBarDrawerToggle as the DrawerListener
drawerLayout.setDrawerListener(actionBarDrawerToggle);
getActionBar().setDisplayHomeAsUpEnabled(true);
//ADD SHADOW TO THE RIGHT EDGE OF DRAWER
drawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
//Responding to clicks implementation:
drawerListView.setOnItemClickListener(new DrawerItemClickListener());
}
#Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
//Sync the toggle state after onRestart... has occurred
actionBarDrawerToggle.syncState();
}
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
actionBarDrawerToggle.onConfigurationChanged(newConfig);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.intro, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
//Call ActionBarDrawerToggle.onOptionsItemSelected(),
//If it returns true, then it has handles the app icon touch event
if (actionBarDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
return super.onOptionsItemSelected(item);
}
private class DrawerItemClickListener implements ListView.OnItemClickListener {
#Override
public void onItemClick(AdapterView parent, View view, int position,
long id) {
//I WOULD LIKE TO REPLACE THE FOLLOWING CODE WITH SOMETHING
//THAT CAN START A NEW ACTIVITY
/*Toast.makeText(IntroActivity.this, ((TextView)view).getText(),
Toast.LENGTH_LONG).show(); */
drawerLayout.closeDrawer(drawerListView);
}
}
}
Thanks if you can help.

Use this
Intent intent = new Intent(IntroActivity.this, YourNewActivity.class);
startActivity(intent);
where YourNewActivity is the activity you want to start