Develop Reference

How can I make Gridview get filled AFTER save is clicked?

Im developing a contacts app, and for now Ive been trying to get this drawables from the array get uploaded into the Gridview on the main screen AFTER the save mosaic button is clicked in the mosaic creation screen.
the floating action button (red plus button) on the mosaicListScreen (main screen) leads to the MosaicCreationScreen). the user hypothetically uploads the image and enters the mosaic name then saves using the save mosaic button, as can be seen in the image here
For now, before I focus on uploading image and letting the user create their own unique mosaics (groups), Im testing the Gridview updating with some drawables, which are listed in the array as can be seen in the code below.
The issue thats occuring is as soon as the user clicks the floating action button on the main screen, it updates the gridview with the drawables listed in the array of the MosaicCreation Screen, THEN it goes to the MosaicCreationScreen, and when save mosaic button is clicked on the MosaicCreationScreen, the intent goes to the main screen as its supposed to do, except the gridview will have nothing on it.
so its like its doing the opposite of whats supposed to happen in steps.
here is my code for the two screens:
public class mosaicsListScreen extends AppCompatActivity {
public static mosaicsListScreen theScreen; //this variable is used in the MosaicCreationScreen to point to this screen to find the GridView by id
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
theScreen = this;
setContentView(R.layout.activity_mosaics_list_screen);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.createMosaicButton);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(getApplicationContext(),MosaicCreationScreen.class);
startActivity(intent);
finish();
}
});
}
}
here is the code for the MosaicCreationScreen (the one that opens after user clicks floating action button from mosaicListScreen (main screen))
public class MosaicCreationScreen extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mosaic_creation_screen);
final GridView mosaicList = (GridView) mosaicsListScreen.theScreen.findViewById(R.id.mosaicList);
mosaicList.setAdapter(new ImageAdapter(this)); //this line of code displays the mosaics on mosaicListScreen
Button saveNewMosaicButton = (Button) findViewById(R.id.saveNewMosaicButton);
saveNewMosaicButton.setOnClickListener(new AdapterView.OnClickListener() {
#Override
public void onClick(View view) {
//mThumbIds.notify();
Intent intent = new Intent(getApplicationContext(), mosaicsListScreen.class);
startActivity(intent);
finish();
//mosaicList.setAdapter(new ImageAdapter(this)); //this displays the mosaics on mosaicListScreen, it logically should go here, however "this" causes an error saying ImageAdapter (android.content.Context) in ImageAdapter cannot be applied to (anonymous android.view.View.OnClickListener)
Toast.makeText(mosaicsListScreen.theScreen, "Mosaic Created!", Toast.LENGTH_SHORT).show();
}
});
/* mosaicList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Toast.makeText(mosaicsListScreen.theScreen, "", Toast.LENGTH_SHORT).show();
}
});*/
}
public class ImageAdapter extends BaseAdapter {
private Context mContext;
public ImageAdapter(Context c) {
mContext = c;
}
public int getCount() {
return mThumbIds.length;
}
public Object getItem(int position) {
return null;
}
public long getItemId(int position) {
return 0;
}
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView = new ImageView(mContext);
imageView.setImageResource(mThumbIds[position]);
return imageView;
}
//this array holds the drawables that would appear on the Gridview
private Integer[] mThumbIds = {
R.drawable.family,
R.drawable.project
};
}
}
Here are the XML for the layouts:
content_mosaics_list_screen.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="codesages.mosaic.mosaicsListScreen"
tools:showIn="#layout/activity_mosaics_list_screen">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="#string/create_a_mosaic_or_pick_from_the_mosaics_created"
android:id="#+id/textView4"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:textSize="20sp" />
<ImageButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/deleteMosaicButton"
android:src="#android:drawable/ic_menu_delete"
android:clickable="true"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:contentDescription="" />
<GridView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/textView4"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="14dp"
android:id="#+id/mosaicList"
android:layout_above="#+id/textView7"
android:numColumns="auto_fit" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:text="#string/holdMosaictoDeleteLabel"
android:id="#+id/textView7"
android:layout_marginBottom="16dp"
android:layout_above="#+id/deleteMosaicButton"
android:layout_centerHorizontal="true" />
</RelativeLayout>
activity_mosaics_list_screen.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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:fitsSystemWindows="true"
tools:context="codesages.mosaic.mosaicsListScreen">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<android.support.design.widget.FloatingActionButton
android:id="#+id/createMosaicButton"
android:layout_width="56dp"
android:layout_height="66dp"
android:layout_gravity="bottom|end"
android:layout_margin="#dimen/fab_margin"
android:src="#android:drawable/ic_input_add" />
<include layout="#layout/content_mosaics_list_screen" />
</android.support.design.widget.CoordinatorLayout>
activity_mosaic_creation_screen.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="codesages.mosaic.MosaicCreationScreen"
android:focusable="true">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/mosaicNametextField"
android:hint="Mosaic Name"
android:layout_marginTop="81dp"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Save New Mosaic"
android:id="#+id/saveNewMosaicButton"
android:layout_marginTop="48dp"
android:layout_below="#+id/uploadMosaicImageButton"
android:layout_centerHorizontal="true"
android:enabled="true"
android:clickable="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Upload Mosaic Image"
android:id="#+id/uploadMosaicImageButton"
android:layout_marginTop="68dp"
android:layout_below="#+id/mosaicNametextField"
android:layout_centerHorizontal="true"
android:enabled="true"
android:clickable="true" />
</RelativeLayout>
mosaicList.setAdapter(new ImageAdapter(this));
thats what appears to be creating the mosaics. if i comment this out, i wont see anything in the gridview.
however, i believe that should be inside the saveNewMosaicButton onClick, but I am getting an error that says "saying ImageAdapter (android.content.Context) in ImageAdapter cannot be applied to (anonymous android.view.View.OnClickListener)"
HERE is an image example of what the desired result should be. however whats happening right now is as ive stated, as soon as the floating action button is clicked, the mosaics are created, THEN it takes you to the creation screen, in which wehn i click save mosaics, it actually erases the mosaics...a job of the trash icon which is too soon to function for now heh.
appreciate help on this

Currently, you have
public static mosaicsListScreen theScreen;
in your first Activity which you use to fill the ListView in this first Activity. This is a dangerous approach because the Activity instance referenced by this variable may be destroyed, for example if you're doing work in your second Activity (e.g. downloading images) which uses much memory, but also if the user somehow triggers a configuration change.
As you are calling finish() after starting the second Activity, you even tell the system that the first Activity may be destroyed. The only reason you did not get a NPE is that the system destroys the finished Activity not instantly but as soon as it seems a good idea to do so.
All in all, you need a way to safely transmit information from one Activity to the other. In your case, I think you would like to send the Uri of the selected images ( or for now, send the resource id of the selected drawables). Both can be accomplished by using Intent extras.
Basically, there are two options:
use startActivityForResult() and override onActivityResult() to obtain the desired information for the first Activity
simply start the first Activity from the second Activity once you have the result and use getIntent() in the first Activity (e.g. in onCreate()) to check for results
No matter what you do, always access UI elements like the ListView in the Activity to which they belong!
If you choose the second option, your first Activity could look like this:
public class mosaicsListScreen extends AppCompatActivity {
public static final String THUMB_IDS = "someuniquestring";
private GridView mosaicList;
private ArrayList<Integer> mThumbIds;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mosaics_list_screen);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.createMosaicButton);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(getApplicationContext(),MosaicCreationScreen.class);
startActivity(intent);
finish();
}
});
fillThumbIds();
mosaicList = (GridView) findViewById(R.id.mosaicList);
// Note: Adapter code in this Activity
mosaicList.setAdapter(new ImageAdapter(this));
}
private void fillThumbIds()
{
mThumbIds = new ArrayList();
// somehow get older thumb ids if necessary (from database?)
// and add to ArrayList like this:
mThumbIds.add(R.drawable.family);
mThumbIds.add(R.drawable.project);
// assuming we transmit resource id's: use an int array with the Intent
int[] newThumbIds = getIntent().getIntArrayExtra(THUMB_IDS);
if (newThumbIds != null)
{
// loop through the array to add new thumb ids
for (int i = 0; i < newThumbIds.length; i++) {
mThumbIds.add(newThumbIds[i]);
}
}
}
// Adapter code goes here
// Note: thumbIds no longer as array but as ArrayList!
}
In the second Activity, you put the selected thumb ids as Intent extra as follows:
saveNewMosaicButton.setOnClickListener(new AdapterView.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(getApplicationContext(), mosaicsListScreen.class);
// if 'myNewThumbs' is the int array with the new thumb ids
intent.putExtra(mosaicsListScreen.THUMB_IDS, myNewThumbs);
startActivity(intent);
finish();
}
});

Expanding/Collapsing CardView with click or swipe gesture (Android)?

I'm looking for a solution to this that will allow me to expand a cardview to see more information and then easily collapse it. Google Keep has examples of cards like this. Anyone know how they do this? Would I create 2 versions of my cardview (one collapsed and one expanded) and then use an Animator class coupled with gesture methods to transition between the two views? I'm using a Recyclerview to hold my cardviews.
I found this if it is at all relevant: http://developer.android.com/training/animation/layout.html

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/tools"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:layout_width="match_parent"
android:orientation="vertical"
android:animateLayoutChanges="true"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
//here put the view which is always visible
<LinearLayout
android:layout_width="match_parent"
android:visibilty="gone"
android:id="#+id/expandableLayout"
android:layout_height="wrap_content">
//here put which will collapse and expand
</LinearLayout>
</android.support.v7.widget.CardView>
take a boolean isexpanded in you arraylist object class
if (listobj.isexpanded)
{
holder.expandableLayout.setVisibility(View.VISIBLE);
}
else {
holder.expandableLayout.setVisibility(View.GONE);
}
holder.cardView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (listobj.isexpanded)
{
holder.expandableLayout.setVisibility(View.GONE);
listobj.isexpanded=false;
notifyItemChanged(position);
}
else {
holder.expandableLayout.setVisibility(View.VISIBLE);
listobj.isexpanded=true;
notifyItemChanged(position);
}
}
});
try someting like this

Animation starts only after I've touched the screen

I have a layout with a top bar container and a content container. When clicking on a button in the top bar, a vertical menu is displayed using an animation. My minSdkVersion is 9.
This works well when I start the app and I still haven't clicked a menu button (i.e. the content fragment has not changed), but as soon as I have clicked an option (and then replace the fragment in the content_container), the vertical menu behaves erratically. The click event of the menu btn is properly triggered, but the vertical menu is not always shown (but sometimes it is...). However, when I click the button and then touch the screen, the animation (show or hide the menu) starts.
I guess it has something to do with the vertical menu overlapping the content fragment, and then replacing the content fragment modify it in some way, but I can't find any solution.
Anybody can help?
top bar fragment
#Override
public void onActivityCreated (Bundle savedInstanceState){
super.onActivityCreated(savedInstanceState);
toggleMenu(0);
Button btn_menu = (Button) getView().findViewById(R.id.btn_menu);
btn_menu.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
mVerticalMenu.setVisibility(View.VISIBLE);
toggleMenu(1000);
}
});
}
private void toggleMenu(int duration){
if(mMenuIsOpen){
TranslateAnimation anim1 = new TranslateAnimation(0,0,0,-(mHeight-mMenuVerticalOffset));
anim1.setFillAfter(true);
anim1.setDuration(duration);
mVerticalMenu.setAnimation(anim1);
AlphaAnimation anim2 = new AlphaAnimation(0.7f, 0.0f);
anim2.setFillAfter(true);
anim2.setDuration(duration);
menu_option_01.setOnClickListener(null);
menu_option_02.setOnClickListener(null);
menu_option_03.setOnClickListener(null);
mMenuIsOpen = false;
}
else{
TranslateAnimation anim1 = new TranslateAnimation(0,0,-(mHeight-mMenuVerticalOffset),0);
anim1.setFillAfter(true);
anim1.setDuration(duration);
mVerticalMenu.setAnimation(anim1);
AlphaAnimation anim2 = new AlphaAnimation(0.0f, 0.7f);
anim2.setFillAfter(true);
anim2.setDuration(duration);
menu_option_01.setOnClickListener(mButtonClickListener);
menu_option_02.setOnClickListener(mButtonClickListener);
menu_option_03.setOnClickListener(mButtonClickListener);
mMenuIsOpen = true;
}
}
private OnClickListener mButtonClickListener = new OnClickListener()
{
public void onClick(View v)
{
toggleMenu(1000);
if(!v.isSelected()){
FragmentTransaction fragmentTransaction = getActivity().getSupportFragmentManager().beginTransaction();
switch(v.getId()){
case R.id.menu_option_01:
// replace content_container by fragment 1
break;
case R.id.btn_02:
// replace content_container by fragment 2
break;
case R.id.btn_03:
// replace content_container by fragment 3
break;
}
}
}
};
private OnClickListener mBgClickListener = new OnClickListener()
{
public void onClick(View v)
{
toggleMenu(1000);
}
};
Main layout
<RelativeLayout 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" >
<FrameLayout
android:id="#+id/content_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingTop="44dp" />
<FrameLayout
android:id="#+id/top_bar_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipChildren="false" />
</RelativeLayout>
top bar layout
<RelativeLayout 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"
android:background="#00000000" >
<LinearLayout
android:id="#+id/vertical_menu"
android:layout_width="50dp"
android:layout_height="match_parent"
android:layout_marginTop="44dp"
android:background="#ffffff"
android:orientation="vertical"
android:visibility="gone" >
<!-- menu layout -->
</LinearLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="44dp"
android:background="#ffffff" >
<Button
android:id="#+id/btn_menu"
android:layout_width="50dp"
android:layout_height="44dp"
android:background="#drawable/menubtn" />
<ImageView
android:layout_width="130dp"
android:layout_height="44dp"
android:src="#drawable/logo"
android:layout_alignParentRight="true" />
</RelativeLayout>
</RelativeLayout>

At the end of my Toggle method, I invalidate the root view:
rootView.invalidate();
and now it works. Not quite clear why I must do that though...

I know there is already an accepted answer for this but I had a similar problem and the answer didnt help.
I had a view that I declared at the end of my layout to keep its Z index above its siblings. I had to touch the page to make the animation work.
So I set the Z index again through Java and it worked.
view.bringToFront();

Remove unnecessary margins from a custom dialog

I have a problem that I am designing a custom dialog for this. I am creating a xml for this as Framelayout is the root layout, and another framelayout with a gray background image is used for the contents, in which I have added a textview and two buttons Ok and Cancel and use all of this through dialog.setContentView(desired Xml Resource);
But when I generate that particular dialog then it shows extra spaces from each side, or we can say that extra margins are there but I don't know how it will removed? Please review the image attached with this question and suggest me the right solution.
Xml Layout:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_height="wrap_content" android:layout_width="wrap_content">
<FrameLayout android:id="#+id/rel"
android:layout_gravity="center_vertical" android:background="#drawable/dialog_box_bg" android:layout_width="wrap_content" android:layout_height="189dp">
<TextView android:id="#+id/tv_LogoutDialog_Text"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:textColor="#424242"
android:text="Are you sure want to logout?" android:textSize="20dip" android:layout_gravity="center_vertical|center_horizontal"></TextView>
<Button android:id="#+id/btn_LogoutDialog_Cancel" android:background="#drawable/dialog_cancel_btn"
android:layout_marginLeft="20dip" android:layout_width="120dip" android:layout_height="42dip" android:layout_gravity="bottom|left" android:layout_marginBottom="15dip"></Button>
<Button android:id="#+id/btn_LogoutDialog_Ok"
android:background="#drawable/dialog_ok_btn_hover"
android:layout_width="120dip"
android:layout_height="42dip" android:layout_marginLeft="180dip" android:layout_gravity="bottom|right" android:layout_marginBottom="15dip" android:layout_marginRight="20dip"></Button>
</FrameLayout>
</FrameLayout>
Code:
#Override
protected Dialog onCreateDialog(int id) {
switch (id) {
case 0:
dialog = new Dialog(HomeScreenActivity.this);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(R.layout.logoutdialog);
btn_cancel = (Button)dialog.findViewById(R.id.btn_LogoutDialog_Cancel);
btn_ok = (Button)dialog.findViewById(R.id.btn_LogoutDialog_Ok);
btn_cancel.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
dismissDialog(0);
}
});
btn_logout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
Intent intent = new Intent(HomeScreenActivity.this,LoginScreen.class);
startActivity(intent);
}
});
return dialog;
}
return null;
}
Thanks in advance.

Don't use
dialog.setContentView(R.layout.logoutdialog);
use
LayoutInflater class to set Dialog content view
Here is link (Check) you can get the idea May this helps you.

Change it by adding a parameter false like in the code below.
dialog.customView(R.layout.dialog_blueprint, false)
The second argument (false) is wrapTheDialogBoxInScrollView. If the content in the dialog box is small and does not require a ScrollView set it to false.

Android: problem creating user form from a menu

I'm very new to programming in Android, but have been struggling all day with a problem and would appreciate your help.
I'm trying to create a form to get user information (essentially a new contact) which is accessed from the menu. When I click the button to create the new form, I get the following error:
"Window already focused, ignoring focus gain of: com.android.internal.view.IInputMethodClient$Stub$Proxy#626fd5e0"
This is my code:
The menu xml:
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="#+id/search"
android:title="#string/settings_search"
android:alphabeticShortcut="#string/settings_shortcut_search" />
<item android:id="#+id/new_contact"
android:title="#string/settings_new"
android:alphabeticShortcut="#string/settings_shortcut_new" />
</menu>
The code for calling the new activity:
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.new_contact:
//activities to create a new account
//startActivity(new Intent(this, Prefs.class));
Intent i = new Intent(MainActivity.this, NewContact.class);
startActivity(i);
//addSaver("String");
return true;
case R.id.search:
return true;
// More items go here (if any) ...
}
return false;
}
The view for the new contact activity:
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">"
<LinearLayout
android:orientation="vertical"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:layout_gravity="top">
<TextView
android:id="#+id/text"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="This is a test\nsecond line\n"/>
<Button
android:id="#+id/new_contact_button"
android:layout_height="wrap_content"
android:text="#string/submit" />
</LinearLayout>
</ScrollView>
And the code for the new activity:
public class NewContact extends Activity implements OnClickListener {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.new_contact);
// Set up click listeners for all the buttons
View newContactButton = findViewById(R.id.new_contact_button);
newContactButton.setOnClickListener(this);
}
Bizarrely if I comment out the button from the class and from the xml then it works correctly and opens up the new activity (but of course I can't do anything with that activity).

In your button xml code, you are missing
android:layout_width="wrap_content"
add that and give it a shot.