RetroArch/android/phoenix/src/com/retroarch/browser/IconAdapter.java

package com.retroarch.browser;

import java.util.List;

import com.retroarch.R;

import android.content.*;
import android.graphics.drawable.*;
import android.view.*;
import android.widget.*;

/**
 * Represents an item that is capable
 * of being within an {@link IconAdapter}.
 */
interface IconAdapterItem {

	/**
	 * Gets whether or not this item is
	 * enabled within the adapter.
	 * <p>
	 * This can be used for deciding whether or
	 * not to enable an item in a {@link ListView}
	 * if an IconAdapter is backing it.
	 * 
	 * @return true if this item is enabled; false otherwise.
	 */
	public boolean isEnabled();

	/**
	 * Gets the title text of this IconAdapterItem.
	 * 
	 * @return the title text of this IconAdapterItem.
	 */
	public String getText();

	/**
	 * Gets the subtitle text of this IconAdapterItem.
	 * 
	 * @return the subtitle text of this IconAdapterItem.
	 */
	public String getSubText();

	/**
	 * Gets the resource ID of the icon to display
	 * alongside the text in this IconAdapterItem.
	 * <p>
	 * Returning zero means no icon is to be displayed.
	 * 
	 * @return the resource ID of this IconAdapterItem's icon.
	 */
	public int getIconResourceId();

	/**
	 * Gets the actual {@link Drawable} object that represents
	 * the icon that is displayed with this IconAdapterItem.
	 * <p>
	 * Returning null means no icon is to be displayed.
	 * 
	 * @return the actual {@link Drawable} of this IconAdapterItem's icon.
	 */
	public Drawable getIconDrawable();
}


/**
 * An {@link ArrayAdapter} derivative that can back a {@link View}
 * that accepts ArrayAdapters. Items within this ArrayAdapter derivative
 * must implement the {@link IconAdapterItem} interface.
 *
 * @param <T> The type of the item that will be within this IconAdapter.
 *            This type must implement the {@link IconAdapterItem} interface.
 */
public final class IconAdapter<T extends IconAdapterItem> extends ArrayAdapter<T> {
	private final int resourceId;
	private final Context context;

	/**
	 * Constructor
	 * 
	 * @param context    The current {@link Context}.
	 * @param resourceId The resource ID for a layout file containing a layout to use when instantiating views.
	 */
	public IconAdapter(Context context, int resourceId) {
		super(context, resourceId);
		this.context = context;
		this.resourceId = resourceId;
	}

	/**
	 * Constructor
	 * 
	 * @param context    The current {@link Context}.
	 * @param resourceId The resource ID for a layout file containing a layout to use when instantiating views.
	 * @param items      The list of items to store within this IconAdapter.
	 */
	public IconAdapter(Context context, int resourceId, List<T> items) {
		super(context, resourceId, items);
		this.context = context;
		this.resourceId = resourceId;
	}

	@Override
	public View getView(int position, View convertView, ViewGroup parent) {
		// Build the view
		if (convertView == null) {
			LayoutInflater inflater = LayoutInflater.from(context);
			convertView = inflater.inflate(resourceId, parent, false);
		}

		// Fill the view
		IconAdapterItem item = getItem(position);
		final boolean enabled = item.isEnabled();

		TextView title = (TextView) convertView.findViewById(R.id.name);
		if (title != null) {
			title.setText(item.getText());
			title.setEnabled(enabled);
		}
		
		TextView subtitle  = (TextView) convertView.findViewById(R.id.sub_name);
		if (subtitle != null) {
			String subText = item.getSubText();
			if (subText != null) {
				subtitle.setVisibility(View.VISIBLE);
				subtitle.setEnabled(item.isEnabled());
				subtitle.setText(subText);
			}
		}

		ImageView imageView = (ImageView) convertView.findViewById(R.id.icon);
		if (imageView != null) {
			if (enabled) {
				final int id = item.getIconResourceId();
				if (id != 0) {
					imageView.setImageResource(id);
				} else {
					imageView.setImageDrawable(item.getIconDrawable());
				}
			} else {
				imageView.setImageDrawable(null);
			}
		}

		return convertView;
	}

	@Override
	public boolean isEnabled(int aPosition) {
		return getItem(aPosition).isEnabled();
	}
}