PageManager.java

/*
* Copyright 2010-2011 Research In Motion Limited.
*
* 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 blackberry.web.widget.loadingScreen;

import net.rim.device.api.ui.TransitionContext;
import net.rim.device.api.ui.Ui;
import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.UiEngineInstance;

import blackberry.web.widget.bf.BrowserFieldScreen;
import blackberry.web.widget.impl.WidgetConfigImpl;

public class PageManager {

    private WidgetConfigImpl _widgetConfigImpl;
    private UiApplication _app;

    private BrowserFieldScreen _screenBrowserField;
    private LoadingScreen _screenLoadingScreen;

    private boolean _firstLaunch;
    private boolean _suppressLoadingScreen;
    private boolean _isGoingBackSafe;

    private static final String PROTOCOL_LOCAL = "local";
    private static final String PROTOCOL_DATA = "data";
    private static final String PROTOCOL_FILE = "file";
    private static final String PROTOCOL_COD = "cod";
    private static final String PROTOCOL_HTTP = "http";
    private static final String PROTOCOL_HTTPS = "https";

    public PageManager( UiApplication app, WidgetConfigImpl widgetConfigImpl ) {
        _app = app;
        _widgetConfigImpl = widgetConfigImpl;

        _firstLaunch = true;
        _suppressLoadingScreen = false;
        _isGoingBackSafe = true;
    }

    public boolean isLoadingScreenRequired( String url ) {
        String protocol = getProtocol( url );

        if( isLocalPageLoadRequired() && protocol.equalsIgnoreCase( PROTOCOL_LOCAL ) ) {
            return true;
        }

        if( isLocalPageLoadRequired() && protocol.equalsIgnoreCase( PROTOCOL_DATA ) ) {
            return true;
        }

        if( isLocalPageLoadRequired() && protocol.equalsIgnoreCase( PROTOCOL_FILE ) ) {
            return true;
        }

        if( isLocalPageLoadRequired() && protocol.equalsIgnoreCase( PROTOCOL_COD ) ) {
            return true;
        }

        if( isRemotePageLoadRequired() && protocol.equalsIgnoreCase( PROTOCOL_HTTP ) ) {
            return true;
        }

        if( isRemotePageLoadRequired() && protocol.equalsIgnoreCase( PROTOCOL_HTTPS ) ) {
            return true;
        }

        return false;
    }

    public boolean isFirstPageLoadRequired() {
        return _widgetConfigImpl.getFirstPageLoad();
    }

    private boolean isRemotePageLoadRequired() {
        return _widgetConfigImpl.getRemotePageLoad();
    }

    private boolean isLocalPageLoadRequired() {
        return _widgetConfigImpl.getLocalPageLoad();
    }

    public void pushScreens( BrowserFieldScreen screenBF2 ) {
        _screenBrowserField = screenBF2;
        _screenLoadingScreen = new LoadingScreen( _widgetConfigImpl, this );

        _app.pushScreen( _screenBrowserField );

        if( isFirstPageLoadRequired() ) {
            _app.pushScreen( _screenLoadingScreen );
        }

        setTransition();
    }

    public boolean isFirstLaunch() {
        return _firstLaunch;
    }

    public void clearFirstLaunch() {
        _firstLaunch = false;
    }

    public boolean isSuppressingLoadingScreen() {
        return _suppressLoadingScreen;
    }

    public void setSuppressLoadingScreen() {
        _suppressLoadingScreen = true;
    }

    public void unsuppressLoadingScreen() {
        _suppressLoadingScreen = false;
    }

    public void setGoingBackSafe( boolean value ) {
        _isGoingBackSafe = value;
    }

    public boolean isGoingBackSafe() {
        return _isGoingBackSafe;
    }

    public void clearFlags() {
        unsuppressLoadingScreen();
        setGoingBackSafe( true );
        clearFirstLaunch();
    }

    public boolean isRedirectableNavigation( String protocol ) {
        return ( protocol.equalsIgnoreCase( PROTOCOL_HTTP ) || protocol.equalsIgnoreCase( PROTOCOL_HTTPS ) );
    }

    public boolean isLocalTextHtml( String contentType ) {
        return ( contentType != null && contentType.equalsIgnoreCase( "text/html" ) );
    }

    private void setTransition() {
        if( _widgetConfigImpl.getTransitionType() != TransitionConstants.TRANSITION_NONE ) {

            TransitionContext transitionContext = null;

            switch( _widgetConfigImpl.getTransitionType() ) {
                case TransitionConstants.TRANSITION_SLIDEPUSH: {
                    transitionContext = new TransitionContext( TransitionContext.TRANSITION_SLIDE );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_KIND, TransitionContext.KIND_IN );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_STYLE, TransitionContext.STYLE_PUSH );
                    break;
                }
                case TransitionConstants.TRANSITION_SLIDEOVER: {
                    transitionContext = new TransitionContext( TransitionContext.TRANSITION_SLIDE );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_KIND, TransitionContext.KIND_IN );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_STYLE, TransitionContext.STYLE_OVER );
                    break;
                }
                case TransitionConstants.TRANSITION_FADEIN: {
                    transitionContext = new TransitionContext( TransitionContext.TRANSITION_FADE );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_KIND, TransitionContext.KIND_IN );
                    break;
                }
                case TransitionConstants.TRANSITION_FADEOUT: {
                    transitionContext = new TransitionContext( TransitionContext.TRANSITION_FADE );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_KIND, TransitionContext.KIND_OUT );
                    break;
                }
                case TransitionConstants.TRANSITION_WIPEIN: {
                    transitionContext = new TransitionContext( TransitionContext.TRANSITION_WIPE );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_KIND, TransitionContext.KIND_IN );
                    break;
                }
                case TransitionConstants.TRANSITION_WIPEOUT: {
                    transitionContext = new TransitionContext( TransitionContext.TRANSITION_WIPE );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_KIND, TransitionContext.KIND_OUT );
                    break;
                }
                case TransitionConstants.TRANSITION_ZOOMIN: {
                    transitionContext = new TransitionContext( TransitionContext.TRANSITION_ZOOM );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_KIND, TransitionContext.KIND_IN );
                    break;
                }
                case TransitionConstants.TRANSITION_ZOOMOUT: {
                    transitionContext = new TransitionContext( TransitionContext.TRANSITION_ZOOM );
                    transitionContext.setIntAttribute( TransitionContext.ATTR_KIND, TransitionContext.KIND_OUT );
                    break;
                }
            }

            if( transitionContext != null ) {
                transitionContext.setIntAttribute( TransitionContext.ATTR_DURATION, _widgetConfigImpl.getTransitionDuration() );
                transitionContext.setIntAttribute( TransitionContext.ATTR_DIRECTION, _widgetConfigImpl.getTransitionDirection() );

                UiEngineInstance engine = Ui.getUiEngineInstance();
                engine
                        .setTransition( _screenBrowserField, _screenLoadingScreen, UiEngineInstance.TRIGGER_PUSH,
                                transitionContext );
            }
        }
    }

    /**
     * Shows the loading screen transition effect.
     */
    public void showLoadingScreen() {    	
    	// Push the screen right away if we are the event thread
        if ( _app.isEventThread() ) {
            if ( _app.getActiveScreen() != _screenLoadingScreen ) {
                _app.pushScreen( _screenLoadingScreen );
            }
        } else {    	
	        _app.invokeLater( new Runnable() {
	            public void run() {	                
                    if( _app.getActiveScreen() != _screenLoadingScreen ) {
                        _app.pushScreen( _screenLoadingScreen );
                    }                
	            }
	        } );
        }
    }

    /**
     * Hides the loading screen transition effect. 
     */
    public void hideLoadingScreen() {
    	// Pop the screen right away if we are the event thread    	
    	if ( _app.isEventThread() ) {
    		try{
                _app.popScreen( _screenLoadingScreen );
    		} catch ( IllegalArgumentException iae ){
    			// Exception is thrown if your screen is not on the stack, which is ok.
    		}
        } else {    	
	        _app.invokeLater( new Runnable() {
	            public void run() {	                
                    /*
                     * Removed the condition checking for "active screen" of the application, since it's not right if there is a
                     * "modal" dialog, because the application will release event lock for "modal" dialog, in order to proceed
                     * next events. So we always pop out _screenLoadingScreen no matter what, and catch the exception if
                     * _screenLoadingScreen was already popped out.
                     */
                    try {
                        _app.popScreen( _screenLoadingScreen );
                    } catch( IllegalArgumentException iae ) {
                        // Exception is thrown if your screen is not on the stack, which is ok.
                    }                
	            }
	        } );
        }
    }

    public boolean isLoadingScreenDisplayed() {
        return ( _app.getActiveScreen() == _screenLoadingScreen );
    }

    public void cancelNewPage() {
        if( _screenBrowserField.getWidgetBrowserField().getHistory().canGoBack() ) {
            setSuppressLoadingScreen();
            _screenBrowserField.getWidgetBrowserField().back();
            hideLoadingScreen();
        }
    }

    private String getProtocol( String url ) {
        if( url != null ) {
            int index = url.indexOf( ":" );
            if( index > 0 ) {
                return url.substring( 0, index ).trim();
            }
        }
        return null;
    }    
}