I am trying to create a nice layout for my list items, but my code only works when it is simplified like this:
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="10dp"
android:textSize="16sp" >
</TextView>
When I add a little bit more it compiles and runs but it force closes on start and gives me the error ArrayAdapter requires ID to be a TextView
:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="?android:attr/listPreferredItemHeight"
android:padding="6dip" >
<ImageView
android:id="@+id/icon1"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_alignParentBottom="true"
android:layout_alignParentTop="true"
android:layout_marginRight="6dip"
android:src="@drawable/ic_launcher" />
<TextView
android:id="@+id/secondLine"
android:layout_width="fill_parent"
android:layout_height="26dip"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_toRightOf="@id/icon1"
android:ellipsize="marquee"
android:singleLine="true"
android:text="Some more information" />
<TextView
android:id="@+id/textView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_above="@id/secondLine"
android:layout_alignParentTop="true"
android:layout_alignWithParentIfMissing="true"
android:layout_toRightOf="@id/icon1"
android:gravity="center_vertical"
android:text="Some Information" />
<ImageView
android:id="@+id/icon2"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:layout_marginRight="6dip"
android:src="@drawable/ic_launcher" />
</RelativeLayout>
and
public class FirstLoginActivity extends ListActivity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String[] testcontacts = getResources().getStringArray(
R.array.testcontacts_array);
setListAdapter(new ArrayAdapter<String>(this, R.layout.list_items,
testcontacts));
ListView lv = getListView();
lv.setTextFilterEnabled(true);
lv.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// When clicked, show a toast with the TextView text
Toast.makeText(getApplicationContext(),
((TextView) view).getText(), Toast.LENGTH_SHORT).show();
}
});
}
I am pretty sure I'm doing this right, I've been through numerous tutorials and I've found that the fastest and most efficient way is to create a static ViewHolder
class. One of the tutorials tried accessing the data directly which is what I was trying to do. I'm still a little confused on how to do so.
public class FirstLoginActivity extends ListActivity {
Context mContext;
List mList;
String[] testcontacts = getResources().getStringArray(
R.array.testcontacts_array);
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setListAdapter(new ArrayAdapter<String>(this, R.layout.list_items,
testcontacts));
ListView lv = getListView();
lv.setTextFilterEnabled(true);
lv.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// When clicked, show a toast with the TextView text
Toast.makeText(getApplicationContext(),
((TextView) view).getText(), Toast.LENGTH_SHORT).show();
}
});
}
public View getView(int position, View convertview, ViewGroup parent) {
ViewHolder holder;
View v = convertview;
if (v == null) {
LayoutInflater inflater = (LayoutInflater) LayoutInflater
.from(mContext);
v = inflater.inflate(R.layout.list_items, null);
holder = new ViewHolder();
holder.firstLine = (TextView) v.findViewById(R.id.firstLine);
holder.secondLine = (TextView) v.findViewById(R.id.secondLine);
holder.icon1 = (ImageView) v.findViewById(R.id.icon1);
holder.icon2 = (ImageView) v.findViewById(R.id.icon2);
v.setTag(holder);
} else {
holder = (ViewHolder) v.getTag();
}
holder.firstLine.setText(testcontacts[position]);
holder.secondLine.setText(testcontacts[position]);
// holder.icon1.setImageBitmap((position & 1) == 1 ? mIcon1: mIcon2);
//call the images directly?
return v;
}
static class ViewHolder {
TextView firstLine;
TextView secondLine;
ImageView icon1;
ImageView icon2;
}
}
See Question&Answers more detail:
os 与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…