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Problem in Android activity: ListView shows no items, even in minimum implementation

the following code does not work as desired.
Does anyone here has a hint?
Thank you in advance,
Sven
Already played around by putting this in onCreate, by making listView, strings, arrayAdapter instance fields and so one. Did not helped.
Making it final or not did not helped.
Changing the length and/or/xor the array's content did not helped.
Activity class:
...
ListView listView = this.findViewById(R.id.listView);
final int n = 10;
String[] strings = new String[n];
for (int i = 0; i < n; i++) {
strings[i] = "X" + i;
}
ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, strings);
Log.d(this, "#1 " + arrayAdapter.getCount());
listView.setAdapter(arrayAdapter);
Log.d(this, "#2 " + listView.getChildCount());
...
Layout:
<?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="fill_parent"
android:layout_height="fill_parent"
android:background="#000000"
android:keepScreenOn="true"
tools:context=".AndroidMainActivity">
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:weightSum="1">
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="0.9">
<ListView
android:id="#+id/listView"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</LinearLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="0.1">
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal"
android:weightSum="1.0">
<Button
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight=".33"
android:background="#007f00"
android:onClick="onClickStart"
android:text="#string/log_start" />
<Button
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight=".34"
android:background="#00007f"
android:onClick="onClickMark"
android:text="#string/mark" />
<Button
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight=".33"
android:padding="0dp"
android:background="#7f0000"
android:onClick="onClickStop"
android:text="#string/log_stop" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
</RelativeLayout>
Instead of showing a list with 10 items, nothing is shown. Debug shows "#1 10" for first and "#2 0" for second statement. I've copied this 1:1 from another well working project incl. the layout XML.

How can I align text of the spinner to the centre?

Here is my XML of the spinner but it did not work.
<Spinner
android:id="#+id/frequency"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/spinner_voices"
android:gravity="center|center_horizontal"
/>

You need to set your own layout for spinner item.
ArrayAdapter adap = new ArrayAdapter<String>(this, R.layout.spinner_item, new String[]{"ABC", "DEF", "GHI"});
spriner.setAdapter(adap);
Where R.layout.spinner_item is a layout with content:
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="fill_parent"
android:layout_width="fill_parent"
android:gravity="center"/>

android-wants to put Button above listview

I am using linear layout inside that one button and one list view..
list-view is adding its item dynamically at the run-time..
so at that time button goes behind list-view and not visible and list-view fit in whole layout.
I want to put Button above the List view and it must also stay after loading list-view
Thanks in Advance
my .xml file is:
<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#000000">
<Button
android:id="#+id/btn_searchNewDevices"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="5dip"
android:layout_gravity="left"
android:background="#000000"
android:textColor="#FFFFFF"
android:text="Search New Devices"
/>
<ListView
android:id="#+id/lst_add_newDevices"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scrollbars="horizontal" >
</ListView>
</LinearLayout>
here it is search new device button.
click on that button device search for Bluetooth and add into listview
so this is thing happen in my application..

I think even this works.Give a try
edited...
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/relative"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Button
android:id="#+id/btn_searchNewDevices"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:layout_marginTop="5dip"
android:text="Search New Devices"
android:textColor="#000000" />
<ListView
android:id="#+id/lst_add_newDevices"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#+id/btn_searchNewDevices"
android:scrollbars="horizontal">
</ListView>
</RelativeLayout>
and the activity is as follows .
public class MainActivity extends Activity implements OnClickListener {
ArrayAdapter<String> adapter;
private Button mBTNSearch;
private static ListView mLV_list;
ArrayList<String> devicesList;
SparseBooleanArray checked;
RelativeLayout layout;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mBTNSearch = (Button) findViewById(R.id.btn_searchNewDevices);
devicesList = new ArrayList<String>();
mLV_list = (ListView) findViewById(R.id.lst_add_newDevices);
adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, devicesList);
mBTNSearch.setOnClickListener(this);
mLV_list.setAdapter(adapter);
}
public void onClick(View v) {
adapter.add("new Device");
adapter.notifyDataSetChanged();
}
}
The output capture is as below

Try using android:layout_weight="1" in the listview's height to that you make sure your button will always be seen in the screen.
You should try:
<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#000000"
android:orientation="vertical" >
<Button
android:id="#+id/btn_searchNewDevices"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:layout_marginTop="5dip"
android:background="#000000"
android:text="Search New Devices"
android:textColor="#FFFFFF" />
<ListView
android:id="#+id/lst_add_newDevices"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:scrollbars="horizontal" >
</ListView>
</LinearLayout>
Or you can use ListView's addHeaderView() method. Here is a tutorial for that.

Try this code for your Layout.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button" />
</LinearLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<ListView
android:id="#+id/listView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
</ListView>
</LinearLayout>

Try putting your listview inside a scrollview.
<Button
android:id="#+id/btn_searchNewDevices"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:layout_marginTop="5dip"
android:background="#000000"
android:text="Search New Devices"
android:textColor="#FFFFFF" />
<ScrollView
android:id="#+id/scroll"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_margin="7dip"
android:scrollbars="none" >
<ListView
android:id="#+id/lst_add_newDevices"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scrollbars="horizontal" >
</ListView>
</ScrollView>
It might work. I haven't tested, so not sure.

How to add fixed buttons above a ListView android?

I want to have two buttons top of a listview. If I scroll below the listview I want that the buttons stay at top. I searched through many solutions on stackoverflow however I could not find the exact one for my case.
My layout xml(mainlayout.xml):
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/latest_news_button" />
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/tracked_news_button" />
</LinearLayout>
<ListView
android:id="#+id/mylist"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
The graphical layout produced is just what I wanted:
Here is my code to use this layout, in case I might fail to bind the Java code to layout;
public class MainActivity extends ListActivity{
Button latestButton;
Button trackedButton;
ListView lv = null;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mainlayout);
latestButton = (Button)findViewById(R.id.button1);
latestButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(MainActivity.this, "Latest Button!", Toast.LENGTH_LONG).show();
}
});
trackedButton = (Button)findViewById(R.id.button2);
trackedButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(MainActivity.this, "Tracked Button!", Toast.LENGTH_LONG).show();
}
});
this.lv = getListView();
String[] values = new String[]{"asdfa","qwerqwer","banbn"};
lv.setAdapter(new ArrayAdapter<String>(BilTrackerMainActivity.this, android.R.layout.simple_expandable_list_item_1, values));
}
however when this activity is called from my other activity my app unfortunately closed. LogCat says:
Your content must have a ListView whose id attribute is 'android.R.id.list'
But I try adding lv = (ListView)findViewById(R.id.mylist); instead of this.lv = getListView();. I could not solve this issue.
I am aware of ListView#addHeaderView but I want to solve my particular problem with using this kind of layout.

Just change your listview id to android:id="#android:id/list"

Use a RelativeLayout. Place the second button to the right of the first button using layout_toRightOf then place the listview beneath button one using layout_below. Something like this (I haven't tested it, apologies for any typos)
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/latest_news_button" />
<Button
android:id="#+id/button2"
android:layout_toRightOf="#id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/tracked_news_button" />
<ListView
android:id="#+id/mylist"
android:layout_below="#id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</RelativeLayout>

Here is the xml you are looking for
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#FF394952">
<LinearLayout
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
style="#android:style/ButtonBar">
<Button
android:id="#+id/btn_AddMore"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/newItem"
android:textColor="#FF394952"/>
</LinearLayout>
<ListView
android:id="#+id/game_list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_weight="1.0" />
</LinearLayout>
And when you design Activity for this dont use List activity directly use Activity and set adapter on the ListView.
ListView lv = (ListView) findViewById(R.id.game_list);
ArrayAdapter<String> listItem = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1, ALBUM_NAME);
lv.setAdapter(listItem);
lv.setTextFilterEnabled(true);

Use below xml file for that
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:id="#+id/mLlayout1" >
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/latest_news_button" />
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/tracked_news_button" />
</LinearLayout>
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/mLlayout1" >
</ListView>
</RelativeLayout>

Create FrameLayout with [your ListView] and [LinearLayout with your buttons].
Do once something like this within onCreate()
LinearLayout myButtons = ...;
myButtons.bringToFront();
So, your ContentView will have a FrameLayout with two child, one of those is in foreground.
That's all. Hope it helped))

static header with dynamic list view troubles

Similar to the contacts view on the androids contacts section, which has the search bar on top with a dynamic list view below it, example here, I am trying to have a spinner instead of a text field.
My problem is that in the layout, the Spinner repeats per list view item.
I have the following list.xml file:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/relativeLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<Spinner
android:id="#+id/spinner1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" />
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/row"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<ImageView
android:id="#+id/icon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/sc" />
<TextView
android:id="#+id/rowData"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
</RelativeLayout>
and the follow Java:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
application = ((MyAppApplication) getApplication());
populateOffers();
}
private void populateOffers()
{
MyAppRequestor MyApp = new MyAppRequestor();
ArrayList<String> list = MyApp.items(application.getMyAppId());
adapter = new ArrayAdapter<String>(this,
R.layout.list, R.id.rowData, list);
setListAdapter(adapter);
}

Since you are using list.xml as your layout it will be repeated.. If you want spinner only once, then you have to put in the main layout (Layout where you have defined the list view as a component.

try this list.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#drawable/bgd" >
<LinearLayout
android:id="#+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<Spinner
android:id="#+id/spinner1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" />
</LinearLayout>
<LinearLayout
android:id="#+id/linearLayout2"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<ImageView
android:id="#+id/icon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/sc" />
<TextView
android:id="#+id/rowData"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>