EPDView.java

/*
 * Copyright (C) 2009-2010 Geometer Plus <contact@geometerplus.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

package org.geometerplus.android.fbreader;

import java.util.LinkedList;

import android.app.Activity;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.os.Handler;
import android.view.View;
import android.widget.EpdRender;
import android.widget.LinearLayout;
import android.widget.TextView;

import org.geometerplus.zlibrary.core.application.ZLApplication;
import org.geometerplus.zlibrary.core.view.ZLView;

import org.geometerplus.zlibrary.text.model.ZLTextModel;
import org.geometerplus.zlibrary.text.view.ZLRect;
import org.geometerplus.zlibrary.text.view.ZLTextView;

import org.geometerplus.zlibrary.ui.android.R;
import org.geometerplus.zlibrary.ui.android.library.ZLAndroidApplication;
import org.geometerplus.zlibrary.ui.android.library.ZLAndroidLibrary;
import org.geometerplus.zlibrary.ui.android.view.ZLAndroidWidget;


abstract class EPDView extends EpdRender implements ZLAndroidLibrary.EventsListener {

	private final Activity myActivity;

	private class ViewHandler extends Handler {
		@Override
		public void handleMessage(android.os.Message msg) {
			switch (msg.what) {
			case 0:
				updateEpdDisplay();
				break;
			case 1:
				updateEpdRegion((ZLRect)msg.obj);
				break;
			case -1:
				myActivity.finish();
				break;
			}
		};
	};
	private final Handler myHandler = new ViewHandler();


	public EPDView(Activity activity) {
		myActivity = activity;
	}

	public final Activity getActivity() {
		return myActivity;
	}

	public void repaintEpd() {
		myHandler.sendEmptyMessage(0);
	}

	public void repaintEpdRect(ZLRect rect) {
		myHandler.sendMessage(myHandler.obtainMessage(1, rect));
	}

	public void finishActivity() {
		myHandler.sendEmptyMessage(-1);
	}


	public interface EventsListener {
		void onPageScrolling();
		void onEpdRepaintFinished();
	}

	private LinkedList<EventsListener> myListeners = new LinkedList<EventsListener>();

	public void addEventsListener(EventsListener listener) {
		myListeners.add(listener);
	}

	public void removeEventsListener(EventsListener listener) {
		myListeners.remove(listener);
	}

	protected final void onPageScrolling() {
		for (EventsListener listener: myListeners) {
			listener.onPageScrolling();
		}
	}


	public final void onEpdRepaintFinished() {
		for (EventsListener listener: myListeners) {
			listener.onEpdRepaintFinished();
		}
	}


	public void onResume() {
		final LinearLayout view = (LinearLayout) myActivity.findViewById(R.id.epd_layout);
		if (view == null) {
			throw new RuntimeException("EPDView's activity must be layed out with \"epd_layout\" layout.");
		}
		setVdsActive(true);
		if (getLayout() != view) {
			bindLayout(view);
		}
		myHandler.sendEmptyMessageDelayed(0, 200);
	}

	public void onPause() {
		setVdsActive(false);
	}

	@Override
	public boolean onPageUp(int arg1, int arg2) {
		final int angle = ZLAndroidApplication.Instance().RotationFlag;
		scrollPage(angle == ZLAndroidApplication.ROTATE_90 || angle == ZLAndroidApplication.ROTATE_180);
		return true;
	}

	@Override
	public boolean onPageDown(int arg1, int arg2) {
		final int angle = ZLAndroidApplication.Instance().RotationFlag;
		scrollPage(angle == ZLAndroidApplication.ROTATE_0 || angle == ZLAndroidApplication.ROTATE_270);
		return true;
	}

	public final void scrollPage(boolean forward) {
		final ZLView view = ZLApplication.Instance().getCurrentView();
		if (view instanceof ZLTextView) {
			onPageScrolling();
			((ZLTextView) view).scrollPage(forward, ZLTextView.ScrollingMode.NO_OVERLAPPING, 0);
			ZLApplication.Instance().repaintView();
		}
	}

	public void updateEpdDisplay() {
		updateEpdStatusbar();
		updateEpdView();

		final View bar = myActivity.findViewById(R.id.statusbar_layout);

		if (bar.getWidth() != 0 && bar.getHeight() != 0) {
			final int left = bar.getLeft();
			final int top = bar.getTop();
			final int right = left + bar.getWidth();
			final int bottom = top + bar.getHeight();
			final Rect rect = new Rect(left + bar.getPaddingLeft(), top + bar.getPaddingTop(),
				right + bar.getPaddingRight(), bottom + bar.getPaddingBottom());
			partialUpdateEpdView(rect);
		}
	}

	private void updateEpdRegion(ZLRect rect) {
		final ZLAndroidWidget widget = (ZLAndroidWidget)myActivity.findViewById(R.id.main_view_epd);

		final Canvas canvas = getEpdCanvas();
		widget.draw(canvas);

		final Rect region = widget.convertRect(rect);

		final int minLeft = 3;
		final int maxRight = widget.getWidth() - 4;
		final int minTop = 3;
		final int maxBottom = widget.getHeight() - 1;

		region.left = Math.max(region.left, minLeft);
		region.top = Math.max(region.top, minTop);
		region.right = Math.min(region.right, maxRight);
		region.bottom = Math.min(region.bottom, maxBottom);

		final int minWidth = 160;
		if (region.width() < minWidth) {
			final int dx = (minWidth + 1 - region.width()) / 2;
			if (region.left < minLeft + dx) {
				region.right += 2 * dx;
			} else if (region.right > maxRight - dx) {
				region.left -= 2 * dx;
			} else {
				region.left -= dx;
				region.right += dx;
			}
		}
		partialUpdateEpdView(region);
	}

	private void updateEpdStatusbar() {
		final TextView statusPositionText = (TextView) myActivity.findViewById(R.id.statusbar_position_text);
		String positionText = "";
		final ZLView view = ZLApplication.Instance().getCurrentView();
		if (view instanceof ZLTextView) {
			ZLTextView textView = (ZLTextView) view;
			ZLTextModel model = textView.getModel();
			if (model != null && model.getParagraphsNumber() != 0) {
				if (textView.getContext().getWidth() == 0
						|| textView.getContext().getHeight() == 0) {
					((ZLAndroidWidget)myActivity.findViewById(R.id.main_view_epd)).resetContext();
				}
				final int page = textView.computeCurrentPage();
				final int pagesNumber = textView.computePageNumber();
				positionText = makePositionText(page, pagesNumber);
			}
		}
		statusPositionText.setText(positionText);
	}

	public static String makePositionText(int page, int pagesNumber) {
		return "" + page + " / " + pagesNumber;
	}
}