Uso de la biblioteca Picasso con ListView

Lo que estoy tratando de hacer es adaptar mi adaptador ListView personalizado para utilizar las imágenes obtenidas de la web por la biblioteca de Picasso. Creo que he cambiado mi adaptador para aceptar una imagen de Picasso, pero no estoy seguro de cómo cambiar mi implementación para aceptarlo usando un ListView. Creo que tengo que tener acceso a holder.imageIcon, pero no estoy seguro de cómo hacerlo funcionar. Mi código es el siguiente.

Historia.java

public class History { public String score; public String gametype; public Picasso icon; public History() { super(); } public History(String score, String gametype, Picasso icon) { super(); this.score = score; this.gametype = gametype; this.icon = icon; } }

HistoryAdapter.java

 public class HistoryAdapter extends ArrayAdapter<History> { Context context; int layoutResId; History data[] = null; public HistoryAdapter(Context context, int layoutResId, History[] data) { super(context, layoutResId, data); this.layoutResId = layoutResId; this.context = context; this.data = data; } @Override public View getView(int position, View convertView, ViewGroup parent) { HistoryHolder holder = null; if(convertView == null) { LayoutInflater inflater = ((Activity)context).getLayoutInflater(); convertView = inflater.inflate(layoutResId, parent, false); holder = new HistoryHolder(); holder.imageIcon = (ImageView)convertView.findViewById(R.id.icon); holder.textTitle = (TextView)convertView.findViewById(R.id.gameType); holder.textScore = (TextView)convertView.findViewById(R.id.score); convertView.setTag(holder); } else { holder = (HistoryHolder)convertView.getTag(); } History history = data[position]; holder.textScore.setText(history.score); holder.textTitle.setText(history.gametype); holder.imageIcon.setImageResource(history.icon); return convertView; } static class HistoryHolder { ImageView imageIcon; TextView textTitle; TextView textScore; } }

Implementación

 History[] historyData = new History[games.length()]; for(int i = 0; i < games.length(); i++) { JSONObject c = games.getJSONObject(i); JSONObject gameStats = games.getJSONObject(i).getJSONObject(TAG_STATS); type[i] = c.getString(TAG_TYPE); champId[i] = c.getString("championId"); cs[i] = gameStats.getString("minionsKilled"); kills[i] = gameStats.getString("championsKilled"); deaths[i] = gameStats.getString("numDeaths"); assists[i] = gameStats.getString("assists"); win[i] = gameStats.getString("win"); if(win[i].equals("true")) win[i] = "Victory"; else win[i] = "Defeat"; if(type[i].equals("RANKED_SOLO_5x5")) type[i] = "Ranked (Solo)"; if(type[i].equals("CAP_5x5")) type[i] = "TeamBuilder"; if(type[i].equals("NORMAL")) type[i] = "Unranked"; score[i] = kills[i] +"/" + deaths[i] + "/" + assists[i]; historyData[i] = new History(score[i], champId[i], R.drawable.ic_launcher); // Placeholder image } if(historyData == null) { historyData[0] = new History("No game found", "N/A", R.drawable.ic_launcher); // Use Picasso placeholder Log.i("Data", "" + historyData); } adapter = new HistoryAdapter(MatchHistoryActivity.this, R.layout.list_adapter, historyData); list.setAdapter(adapter);

List_item.xml

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="?android:attr/listPreferredItemHeight" android:background="#111111" android:padding="6dip" > <ImageView android:id="@+id/icon" android:layout_width="wrap_content" android:layout_height="fill_parent" android:layout_alignParentBottom="true" android:layout_alignParentTop="true" android:layout_marginRight="6dip" android:contentDescription="TODO" android:src="@drawable/ic_launcher" /> <TextView android:id="@+id/score" android:textColor="#C49246" android:layout_width="fill_parent" android:layout_height="26dip" android:layout_alignParentBottom="true" android:layout_alignParentRight="true" android:layout_marginLeft="5dp" android:layout_toRightOf="@id/icon" android:ellipsize="marquee" android:singleLine="true" android:text="0/0/0 KDA" android:textSize="12sp" /> <TextView android:id="@+id/gameType" android:textColor="#C49246" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_above="@id/score" android:layout_alignParentRight="true" android:layout_alignParentTop="true" android:layout_alignWithParentIfMissing="true" android:layout_marginLeft="5dp" android:layout_toRightOf="@id/icon" android:gravity="center_vertical" android:textSize="16sp" /> </RelativeLayout>

Hay 2 cosas que usted necesita cambiar: 1) History.icon debe ser el URL de la String del icono, no un objeto de Picasso . También puede utilizar un File , Uri o int , pero un url String es probablemente lo que desea.

2) Modifique el método getView() su Adapter's para cargar el icono usando Picasso (vea la última línea antes de getView() devuelve el convertView ):

 public class HistoryAdapter extends ArrayAdapter<History> { Context context; int layoutResId; History data[] = null; public HistoryAdapter(Context context, int layoutResId, History[] data) { super(context, layoutResId, data); this.layoutResId = layoutResId; this.context = context; this.data = data; } @Override public View getView(int position, View convertView, ViewGroup parent) { HistoryHolder holder = null; if(convertView == null) { LayoutInflater inflater = ((Activity)context).getLayoutInflater(); convertView = inflater.inflate(layoutResId, parent, false); holder = new HistoryHolder(); holder.imageIcon = (ImageView)convertView.findViewById(R.id.icon); holder.textTitle = (TextView)convertView.findViewById(R.id.gameType); holder.textScore = (TextView)convertView.findViewById(R.id.score); convertView.setTag(holder); } else { holder = (HistoryHolder)convertView.getTag(); } History history = data[position]; holder.textScore.setText(history.score); holder.textTitle.setText(history.gametype); Picasso.with(this.context).load(history.icon).into(holder.imageIcon) return convertView; } static class HistoryHolder { ImageView imageIcon; TextView textTitle; TextView textScore; } }