RefreshActionProvider.java

package com.jdroid.android.refresh;

import android.content.Context;
import android.graphics.Rect;
import android.support.v4.view.ActionProvider;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnLongClickListener;
import android.widget.ImageButton;
import android.widget.Toast;
import android.widget.ViewSwitcher;
import com.jdroid.android.R;

public class RefreshActionProvider extends ActionProvider {
	
	public interface OnRefreshListener {
		
		public void onRefresh();
	}
	
	private static final int BUTTON_VIEW = 0;
	private static final int PROGRESS_VIEW = 1;
	
	private OnRefreshListener onRefreshClickListener;
	private ViewSwitcher viewSwitcher;
	private CharSequence title;
	
	public RefreshActionProvider(final Context context) {
		super(context);
		
		viewSwitcher = (ViewSwitcher)LayoutInflater.from(context).inflate(R.layout.jdroid_refresh_action_item, null);
		
		ImageButton refreshButton = (ImageButton)viewSwitcher.findViewById(R.id.refresh_button);
		refreshButton.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				
				viewSwitcher.setDisplayedChild(PROGRESS_VIEW);
				
				if (onRefreshClickListener != null) {
					onRefreshClickListener.onRefresh();
				}
			}
		});
		refreshButton.setOnLongClickListener(new OnLongClickListener() {
			
			@Override
			public boolean onLongClick(View view) {
				showCheatsheet(context, view);
				return true;
			}
		});
	}
	
	@Override
	public View onCreateActionView() {
		return viewSwitcher;
	}
	
	public void setOnRefreshListener(OnRefreshListener onRefreshListener) {
		onRefreshClickListener = onRefreshListener;
	}
	
	public void stopLoading() {
		viewSwitcher.setDisplayedChild(BUTTON_VIEW);
	}
	
	public void startLoading() {
		viewSwitcher.setDisplayedChild(PROGRESS_VIEW);
	}
	
	/**
	 * Slightly modified code, from Jake Wharton's ABS
	 */
	private void showCheatsheet(Context context, View view) {
		
		final int[] screenPos = new int[2];
		final Rect displayFrame = new Rect();
		view.getLocationOnScreen(screenPos);
		view.getWindowVisibleDisplayFrame(displayFrame);
		
		final int width = view.getWidth();
		final int height = view.getHeight();
		final int midy = screenPos[1] + (height / 2);
		final int screenWidth = context.getResources().getDisplayMetrics().widthPixels;
		Toast cheatSheet = Toast.makeText(context, title, Toast.LENGTH_SHORT);
		if (midy < displayFrame.height()) {
			// Show along the top; follow action buttons
			cheatSheet.setGravity(Gravity.TOP | Gravity.RIGHT, screenWidth - screenPos[0] - (width / 2), height);
		} else {
			// Show along the bottom center
			cheatSheet.setGravity(Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, 0, height);
		}
		cheatSheet.show();
	}
	
	public void setTitle(CharSequence title) {
		this.title = title;
	}
}