I am new to Android development. I am using ListView to list some data from SQLite database. my Main.xml file looks like:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/inspections"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<!-- Header -->
<LinearLayout android:id="@+id/header"
android:background="#ff347c12"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
>
<TextView android:id="@+id/item1"
android:layout_height="fill_parent"
android:layout_width="wrap_content"
android:width="100dip"
android:height="30dip"
android:text="Id"
/>
开发者_运维问答 <TextView android:id="@+id/item2"
android:layout_height="fill_parent"
android:layout_width="wrap_content"
android:text="Customer"
android:width="100dip"
android:height="30dip"
/>
<TextView android:id="@+id/item3"
android:layout_height="fill_parent"
android:layout_width="wrap_content"
android:text="Contract"
android:width="100dip"
android:height="30dip"
/>
<TextView android:id="@+id/item4"
android:layout_height="fill_parent"
android:layout_width="wrap_content"
android:text="Inspector"
android:width="100dip"
android:height="30dip"
/>
</LinearLayout>
<!-- List Divider -->
<View android:layout_width="fill_parent"
android:layout_height="1dip"
android:background="?android:attr/listDivider" />
<!-- ListView (grid_items) -->
<LinearLayout android:id="@+id/layout"
android:layout_width="wrap_content"
android:layout_height="fill_parent">
<ListView android:id="@+id/listview"
android:layout_height="fill_parent"
android:layout_width="fill_parent">
</ListView>
</LinearLayout>
</LinearLayout>
I am using grid_item.xml which is used to hold data of each row, it looks like:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView android:id="@+id/item1"
android:text="row_id"
android:layout_height="fill_parent"
android:layout_width="wrap_content"
android:width="20dip"
/>
<TextView android:id="@+id/item2"
android:text="col_1"
android:layout_height="fill_parent"
android:layout_width="wrap_content"
android:width="100dip"
/>
<TextView android:id="@+id/item3"
android:text="col_2"
android:layout_height="fill_parent"
android:layout_width="wrap_content"
android:width="100dip"
/>
<TextView android:id="@+id/item4"
android:text="col_3"
android:layout_height="fill_parent"
android:layout_width="wrap_content"
android:width="100dip"
/> </LinearLayout>
Code:
public class Inspections extends Activity{
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
try
{
super.onCreate(savedInstanceState);
setContentView(R.layout.inspections);
LoadInspections();
}
catch (Exception e) {
CommonMethods.ShowMessageBox(this, e.toString());
}
}
private void LoadInspections()
{
try
{
DBAdapter db = new DBAdapter(this);
db.open();
Cursor cur = db.GetInspections();
if(cur.moveToFirst())
{
startManagingCursor(cur);
ListView lv = (ListView)findViewById(R.id.listview);
// create the grid item mapping
String[] from = new String[] {"_id", "customer", "contract", "inspector"};
int[] to = new int[] {R.id.item1, R.id.item2, R.id.item3, R.id.item4 };
// fill in the grid_item layout
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.grid_item, cur, from, to);
lv.setAdapter(adapter);
Log.d("Inspection", "Records found " + cur.getString(1) + "/ "+ cur.getString(2)+ "/ "+ cur.getString(3));
}
else
{
Log.d("Inspection", "No reords");
}
db.close();
}
catch(Exception ex)
{
Log.d("Inspection", "Error: "+ ex.toString());
}
}
}
Problem: There is something wrong with LoadInspections(), the list-view show no data but only the HEADER-ROW. The cursor is retrieving data, check this line:
Log.d("Inspection", "Records found " + cur.getString(1) + "/ "+ cur.getString(2)+ "/ "+ cur.getString(3));
The log window is displaying the data.
I tried my best to find the answer on stackoverflow but could not succeeded. Thanks in advance for your valuable time & help.
I was trying different things & when i removed the "Header" & "List Divider" sections from my main.xml it worked. Very Strange??
So my main.xml now looks like:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/inspections"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<!-- ListView (grid_items) -->
<LinearLayout android:id="@+id/layout"
android:layout_width="wrap_content"
android:layout_height="fill_parent">
<ListView android:id="@+id/mylistview"
android:layout_height="fill_parent"
android:layout_width="fill_parent">
</ListView>
</LinearLayout>
</LinearLayout>
Can somebody comment on this strange behavior of listview?
You might have already found out but, the primary LinearLayout has a horizontal orientation. Every child view that you will add will be added horizontally next to it. Since your first view, "@+id/header", takes up the whole width of the screen the other views will be added outside of the screen.
If you change the orientation of "@+id/inspections" into "vertical" all your views will be visible.
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