UIPageControl.java

/*
 * Copyright (C) 2012 Wu Tong
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.cocoa4android.ui;

import org.cocoa4android.R;
import org.cocoa4android.cg.CGPoint;
import org.cocoa4android.cg.CGRect;
import org.cocoa4android.ns.NSMutableArray;

import android.view.ViewGroup;

public class UIPageControl extends UIView{
	private int numberOfPages;
	private int currentPage;
	private CGPoint center;
	
	public void setCenter(CGPoint center){
		super.setCenter(center);
		this.center = CGPointMake(center.x, center.y);
	}
	public void setFrame(CGRect frame){
		super.setFrame(frame);
		this.center = null;
	}
	private NSMutableArray dots = NSMutableArray.arrayWithCapacity(10);
	
	
	public int getNumberOfPages() {
		return numberOfPages;
	}

	public void setNumberOfPages(int numberOfPages) {
		this.numberOfPages = numberOfPages;
		//remove all child
		ViewGroup vg = (ViewGroup)this.getView();
		vg.removeAllViews();
		dots.removeAllObjects();
		
		//resize uiview
		CGRect appFrame = UIScreen.mainScreen().applicationFrame();
		int singleWidth = (int) (appFrame.size.width/45.0);
		int realWidth = singleWidth*(2*numberOfPages+1);
		int realHeight = singleWidth;
		CGRect frame = this.frame();
		frame.size.width = realWidth;
		frame.size.height = realHeight;
		
		if (center!=null) {
			//fix position
			frame.origin.x = (int) (center.x-frame.size.width/2);
			frame.origin.y = (int) (center.y-frame.size.height/2);
		}
		super.setFrame(frame);
		
		//add new child
		for (int i = 0; i < numberOfPages; i++) {
			UIImageView imageView = null;
			if (i==0) {
				imageView = new UIImageView(new UIImage(R.drawable.zz_c4a_pagecontrol_active));
				currentPage = 0;
			}else{
				imageView = new UIImageView(new UIImage(R.drawable.zz_c4a_pagecontrol_dim));
			}
			imageView.setFrame(CGRectMake(singleWidth*(i*2+1), 0, singleWidth, singleWidth));
			this.addSubview(imageView);
			dots.addObject(imageView);
		}
	}

	public int currentPage() {
		return currentPage;
	}

	public void setCurrentPage(int currentPage) {
		if (currentPage>=this.numberOfPages||currentPage<0) {
			//invalid
			return;
		}
		if (this.currentPage==currentPage) {
			return;
		}
		UIImageView currentImageView = (UIImageView) dots.objectAtIndex(this.currentPage);
		UIImageView nextImageView = (UIImageView) dots.objectAtIndex(currentPage);
		
		CGRect currentFrame = currentImageView.frame();
		CGRect nextFrame = nextImageView.frame();
		currentImageView.setFrame(nextFrame);
		nextImageView.setFrame(currentFrame);
		dots.replaceObject(this.currentPage, nextImageView);
		dots.replaceObject(currentPage, currentImageView);
		
		this.currentPage = currentPage;
		
	}
}