I'm trying to populate a ListView
with Strings (food item names) on the left side, and item count numbers on the right. I've made a CustomAdapter
class (see below) which extends BaseAdapter
after following some tutorials, where I could see (via print statements) that at least the getCount()
method is called, but my getView()
method doesn't get called and my ListView
doesn't appear on my app. What am I doing wrong? I assume that it's because I don't know how to make getView()
run in the right place. It works fine when I use a normal ArrayAdapter
with an array of strings.
Here is how I tried populating the ListView in my MainActivity class:
CustomAdapter customAdapter = new CustomAdapter();
ListView lv1 = (ListView) findViewById(R.id.listView);
lv1.setAdapter(customAdapter);
customAdapter.notifyDataSetChanged();
Now, here is my CustomAdapter class:
import java.util.ArrayList;
import java.util.List;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;
public class CustomAdapter extends BaseAdapter {
List<foodItem> mItemList = getDataForListView();
public CustomAdapter(List<foodItem> list){
this.mItemList = list;
// tried this as an alternative
}
@Override
public int getCount() {
return mItemList.size();
}
@Override
public foodItem getItem(int arg0) {
return mItemList.get(arg0);
}
@Override
public long getItemId(int arg0) {
return arg0;
}
@Override
public View getView(int arg0, View arg1, ViewGroup parent) {
System.out.println("Item list size: " + mItemList.size()); // doesn't show anything in console
if(arg1==null) {
LayoutInflater inflater = (LayoutInflater) LayoutInflater.from(parent.getContext());
arg1 = inflater.inflate(R.layout.listrow, parent ,false);
// R.layout.listrow is an XML file defined and formatted at 60sp tall
// as that is how tall I want each item in the ListView to be
}
TextView foodItem = (TextView)arg1.findViewById(R.id.foodTitle);
TextView likeCount = (TextView)arg1.findViewById(R.id.likeCount);
foodItem i = mItemList.get(arg0);
foodItem.setText(i.getItem());
likeCount.setText(i.getLikes());
return arg1;
}
public List<foodItem> getDataForListView() {
List<foodItem> itemList = new ArrayList<foodItem>();
// Test method populating with some data
for(int i=0; i<50; i++) {
itemList.add(new foodItem(i, "Item " + i));
}
return itemList;
}
}
I also tried adding my own constructor, but the result was the same. Any help would be greatly appreciated!
EDIT: The layout for my main activity:
<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="com.example.inventoryList.MainActivity" >
<ListView
android:id="@+id/foodOptions"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="30dp" />
</RelativeLayout>
Last, here is my listrow.xml file:
<?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="60sp"
android:orientation="horizontal"
android:padding="5sp" >
<TextView
android:id="@+id/foodTitle"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:textSize="12sp"
android:text="123"
android:gravity="center" />
<TextView
android:id="@+id/likeCount"
android:layout_width="12sp"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:text="@+string/likeCount"
android:textSize="10sp"
tools:ignore="SmallSp" />
</RelativeLayout>
I fixed it. My Main Activity has three tabs, and for each I set a tab listener that changes what's in the adapter. I had assumed that these tab listeners wouldn't be invoked upon starting the app, but apparently that was not true. In consequence, from things I had commented out in testing, I had been called setAdapter() and passing in an empty adapter.
Thanks for the help all, sorry that it turned out to be a mistake in code that I hadn't provided.