The Different Ways to Style a Schedule

In this blog post we will look at the different levels of sty‌ling the elements and items of a schedule made with a MindFusion scheduling library. In our sample we use the Java Scheduling Library, but the API members that we use and the cascading levels of styling a schedule are universal across all MindFusion Scheduling components.

I. Top Level: Theme

At the top level of styling you have themes. The scheduling library has a set of predefined themes: Light, Lila, Silver, Standard, Vista, Windows2013. You apply one of the predefined themes this way:

calendar.setTheme(ThemeType.Vista);

Here is what the calendar looks like styled with the vista theme:

In JavaScript, the themes are defined in CSS styles and you must reference the desired file and set the name of the theme to the calendar instance. In the other libraries, they are built-in and usually are available as members of an enum.

You have the option to create a custom theme, which you can save and apply this way:

calendar.setCustomTheme(new MyTheme());

Another way to apply the custom theme in Java Scheduling is:

calendar.setCustomTheme(new MyTheme());

Here is the look of the calendar with the custom theme:

The custom theme has changed some of the colors, widened the header so that the week days could be seen and set some borders on the cells.

Creating a custom Theme requires that you override a strict set of methods. They are the public members of the Theme class. You should override all of them. Among the methods that style the calendar for each view – getMonthRangeSettings getMonthSettings etc. You could override in detail only the method that is responsible for styling the view you would use – if it is only one. For the rest of the methods you could just write:

private void initialize_MyTheme_ListViewSettings()
{
	_listViewSettings = super.createListViewSettings();
}

Every method in the Theme class must be dutifully implemented and all settings set. That comes from the fact that a Theme is the last and topmost styling instrument and it must know how to style any element that might not be explicitly styled down the tree.

The online and offline documentations of the Java Scheduling library come with topics that list in details the styling settings for each of the predefined themes. Our advice is that you get the code of the Theme that looks closest to what you want to have as a structure and modify it.

The sample project that you can download at the bottom of this post implements a custom Theme based on the Vista theme and lists all members in a theme that you must set with all details.

II. View and Item Settings

One level down the tree are the view settings properties. They are available for any view. You can access those settings with the getMonthSettings getMonthRangeSettings etc. methods. Each one of those methods returns the styling settings of a particular view. You should use the one that corresponds to the view you’ve chosen:

//set the view to SingleMonth
calendar.setCurrentView(CalendarView.SingleMonth);
//get the styling settings for SingleMonth view
calendar.getMonthSettings().getDaySettings().setTodayFillColor(Color.green);

You can style the items, regardless of the view used, with the ItemSettings object:

calendar.getItemSettings().setPadding(20);

The *Settings properties define the appearance of items in terms of alignment, spacing, padding, shadow, date format. The coloring of the elements is left to Style instances. Thus, if you want to change the color of items, you will use:

//customize just the items through the itemSettings field
calendar.getItemSettings().setPadding(20);
		
Style itemStyle = new Style();
itemStyle.setBrush(new SolidBrush(Color.white));
itemStyle.setHeaderTextColor(Color.DARK_GRAY);		
itemStyle.setHeaderTextShadowStyle(ShadowStyle.None);
calendar.getItemSettings().setStyle(itemStyle);

This styles all items on the calendar. For styling a particular item, you should use on of the methods listed underneath.

Our calendar now has green header on the current day, the background of events is white and there is a bit of a padding added to the events.

III. Using Events to Style Particular Items

When you want to select items that you want to style based on some distinct characteristics, you can use events. In our sample we handle the itemCreated event, where we check if the start date of an appointment happens to be during the weekend:

// Listen for item creation and for draw events
calendar.addCalendarListener(new CalendarAdapter(){
	//apply custom styling to selected items
	public void itemCreated(ItemEvent e) {
		onItemCreated(e);
	}				
});

The Java Scheduler provides various events, which are accessible through a CalendarListener and CalendarAdapter instances. We handle the itemCreated event this way:

//color in red events that are scheduled to start on weekends
protected void onItemCreated(ItemEvent e) {

	Item item = e.getItem();
	if(item.getStartTime().getDayOfWeek() == DayOfWeek.Saturday || 
		item.getStartTime().getDayOfWeek() == DayOfWeek.Sunday)
		{
			item.getStyle().setBrush(new SolidBrush(new Color(213, 28, 32)));
			item.getStyle().setHeaderTextColor(Colors.White);
			item.getPointedStyle().setBrush(new SolidBrush(new Color(100, 100, 100)));
		}	
}

The ItemEvent class provides the item that was created and you can use the instance to apply any particular styling to the item.

Here is our scheduler, which now colors the items on weekends in red:

In JavaScript, the items have a special field that allows you to assign to them a custom CSS style that you’ve defined. The style will be applied to the particular item only. The field is called ‘cssClass’.

IV. Custom Drawing

When you need to style in a very unique way calendar elements and nothing else helps, you have the option to draw them the way you want. Custom drawing can be made for many parts of the calendar. The available elements are identified as members of the CustomDrawElements enumeration.

You tell the control that you want to use custom drawing this way:

//specify that we will use custom drawing	
calendar.setCustomDraw(EnumSet.of(CustomDrawElements.CellContents));

The custom drawing must be part of the draw method, which is also a member of CalendarListener:

// Listen for item creation and for draw events
calendar.addCalendarListener(new CalendarAdapter(){
				
			
//add custom drawing to CellContents
@Override()
public void draw(CalendarDrawEvent e) {
	onDraw(e);
	} 
			
});

The event handler method looks like this:

//apply custom drawing to selected items
private void onDraw(CalendarDrawEvent e)
{
	if (e.getElement() == CustomDrawElements.CellContents)
	{
		DateTime date = e.getDate();		
		
		//color in light yellow the background of the first 10 days of a month
		if (date.getDay() < 11)
		{
			// Do the custom drawing
			Rectangle2D bounds = new Rectangle2D.Double(
			e.getBounds().getX(), e.getBounds().getY(),
			e.getBounds().getWidth() - 1, e.getBounds().getHeight() - 1);
			new AwtGraphics(e.getGraphics()).fillRectangle(Brushes.LightYellow, bounds);
		}
	}
}

The Calendar’s drawEvent class gives us useful methods to learn more about the item that is being drawn. In our case we want to draw the cell contents, so we check if draw was called for the cell contents, and if yes, we get the bounds of the element. We need the check, because draw is called for all elements that support custom drawing and we need to identify which one is drawn at the moment.

Thanks to the custom drawing, the monthly schedule now has a light yellow background on the first ten days of the month:

With this our review of the methods to style a schedule is finished. You can download the complete source code of the sample together with all MindFusion libraries used from this link:

How to Style a Java Schedule: Download Project Source Code

You can post questions about Mindusion Scheduling components at MindFusion online forums.

About MindFusion Scheduling Components MindFusion Scheduling components are available for a variety of platforms for web, mobile and desktop programming. All of them include a robust feature set that includes 6 calendar views, predefined themes, various events, predefined forms for creating appointments and recurrence. The components are fully interactive, easy to customize and style and are the ideal choice for any application that needs to implement time management features. You can learn more about MindFusion Scheduling tools at https://mindfusion.eu/scheduling-pack.html.

A Class Diagram Tool in Java with the Flowchart Library – II

This is the second part of MindFusion step-by-step tutorial on how to create a Java application that reads the contents of a *.jar file and renders class diagram of its API. In the previous blog post we looked at the UI elements that build the application – the UI, the legend panel, the diagram elements. Now we continue with reading the class data and building the class diagram.

I. Reading the Data

The data that we need – the name of the API member, its fields, its type – enum, class, interface as well inherited classes – is stored in a helper class that we’ve created for the purpose and that is called MemberInfo.java. It is a simple class that does nothing else than storing data:

 public MemberInfo( String name, String fullName )
    {
        this.name = name;
        this.fullName = fullName;

        //lists for the methods, fields and constructors.
        methods = new ArrayList();
        fields = new ArrayList();
        constructors = new ArrayList();
        inheritsFrom = "";
        packageName = "";
        isInterface = false;
        isEnum = false;
    }

There is a list with the methods, fields and constructors, as well properties for the name of the package, the class this class inherits from as well boolean values that indicate if this is an enum or interface.

For reading the data we use only classes and methods from the official Java packages – no third party tools or libraries:

      try
        {
            //try to open the jar
            JarFile jarFile = new JarFile(pathToJar);

            //explore the elements found in the *.jar.
            Enumeration e = jarFile.entries();

            URL[] urls = {new URL("jar:file:" + pathToJar + "!/")};
            URLClassLoader cl = URLClassLoader.newInstance(urls);
            //if a class is found - read its data
            while (e.hasMoreElements())
            {
                JarEntry je = e.nextElement();
                if (je.isDirectory() || !je.getName().endsWith (".class")) {
                    continue;
                }
                // -6 because of .class file extension.
                String className = je.getName().substring(0, je.getName().length() - 6);
                className = className.replace('/', '.');
                .....

In a cycle we read all classes in the jar, parse the data we are interested in and filter data that is no relevant to us – private methods, abstract classes etc. The data we acquire for each class is stored in a new MemberInfo object that we add to a collection.

II. Diagram Elements

The diagram elements that we use to render each class are TableNode-s. We use the caption field to show the name of the class. In addition, we use the capabilities of the Java diagram library to render formatted text and add to the caption the name of the package – drawn on a new line.

            //create the TableNode
            TableNode _table = diagram.getFactory().createTableNode(10, 10, 5, 5, 2, info.memberCount());
            //set the name of the member and the package as table caption.
            String caption = "" + info.getName() + "";
            if(info.getPackageName().length() > 0)
                caption += "\n" + info.getPackageName();
            _table.setCaption(caption);
            //center the caption
            _table.setCaptionFormat((new TextFormat(Align.Center, Align.Center)));
            //increase the default caption height
            _table.setCaptionHeight(10f);
           .....

It is important to note here that we add an identifier for each table – this will help us find the right TableNode when we later create connections:


 _table.setId(info.getFullName());

By default TableNode-s are drawn with blue. We check if the current object is enum or interface and change the color scheme accordingly:

            //add enums to the list and paint them green
            if(info.isEnum()) {
                _table.setBrush(new SolidBrush(new Color((int) 210, (int) 250, (int) 208)));
                enums.add(_table);
            }//add interfaces to the list and paint them yellow
            else if(info.isInterface()) {
                _table.setBrush(new SolidBrush(new Color((int) 250, (int) 235, (int) 140)));
                interfaces.add(_table);
            }
            else //the class nodes are blue
                _table.setBrush(new SolidBrush(new Color((int)197, (int)223, (int)238)));

Then we add table rows for the constructors, methods and fields. Each row has a cell for the image and for the definition of the member:

            //fill the first cells with data for the constructors.
            for (String constructor : info.getConstructors())
            {
                _table.getCell(0, index).setImage(constructorImage);
                _table.getCell(1, index).setText(constructor);
                index++;
            }

Finally, we look at all MemberInfo objects and draw DiagramLink between each class and the class it derives from, if any:

  for (MemberInfo info : membersList)
        {
            if(!info.getParent().isEmpty())
            {
                DiagramNode node = diagram.findNodeById (info.getFullName());
                DiagramNode parent = diagram.findNodeById( info.getParent());

                //add inheritance link
                if(node != null && parent != null)
                {
                    DiagramLink link = diagram.getFactory ().createDiagramLink(node, parent);

                .......

III. Containers

Interfaces and enums are drawn in groups at the end of the TableNode-s for classes. This is done using ContainerNode-s. First, we calculate the dimensions of the ContainerNode by measuring all TableNode-s that must fit into it:

            //calculate the location of the node
            int side = (int)Math.ceil(Math.sqrt(tables.size()));
            int rows = (int)Math.ceil((double)tables.size() / side);
            double singleWidth = tables.get(0).getBounds().getWidth();
            double width = 5 * (side + 1) * coef + singleWidth * side;
            double height = (5 * (rows + 1) + 5) * coef;

            double[] rowHeights = new double[rows];
            for (int i = 0; i < tables.size(); i++)
                rowHeights[i / side] = Math.max(tables.get(i).getBounds().getHeight(), rowHeights[i / side]);

            for (double h : rowHeights)
                height += h;


            //initialize the container
            ContainerNode b = diagram.getFactory().createContainerNode (0, 0, width, height);
            ....

Here the variable tables is a list with the TableNode-s that must fit into the container. After the ContainerNode is created, the tables must be added and positioned in it:

            int index = 0;
            for (TableNode e : tables)
            {
                b.add(e);

                double x = (index % side) * (5 + singleWidth);
                double y = 0;

                for (int r = 0; r < index / side; r++)
                    y += 5 * coef + rowHeights[r];

                //adjust the size of the node
                e.setBounds(new Rectangle2D.Double(x + 5 * coef, y + 10 * coef,                   e.getBounds().getWidth(), e.getBounds ().getHeight()));

                index++;
            }

Finally we adjust the appearance of the ContainerNode to make it look better and in line with the TableNode-s:

            //customize the container
            b.setCaption(name);
            b.setCaptionFormat((new TextFormat(Align.Center,  Align.Center)));
            b.setHandlesStyle( HandlesStyle.HatchHandles3 );
            b.setFont(new Font("Verdana", Font.BOLD, 4));
            b.setIgnoreLayout(true);
            b.setTag(tag);
            //no shadow
            b.setShadowOffsetX(0f);
            b.setShadowOffsetY(0f);

It’s important to note that the bounds of the container must be updated for the changes to take effect:

            //update the container size.
            b.updateBounds();

IV. Diagram Layout

The last part of the application deals with diagram layout. This is very important because in the common scenario we expect to read *.jar files with tens of classes and proper visual arrangement of the flowchart is the key to its usability.

We decide to use the TreeLayout, which is meant exactly to arrange diagrams with nodes on several levels as we expect the class hierarchies to be. It is easy to apply the layout – we create an instance of it and after setting some initial customization we call its arrange method:

         TreeLayout layout = new TreeLayout();

        //the layout type is Centered
        layout.setType(TreeLayoutType.Centered);
        //allow reversed links
        layout.setReversedLinks(true);
        //the type of links will be cascading
        layout.setLinkStyle(TreeLayoutLinkType.Cascading3);
        //specify the distance between levels of tree nodes
        layout.setLevelDistance(25);
        //groups must be preserved.
        layout.setKeepGroupLayout(true);

        layout.arrange(diagram);

It is easy to understand the type of the settings we’ve used – thanks to the self-explanatory names of the layout class you can see that we specify that the TreeLayout will be centered, the links will be reversed, then we change the link style and the distance between levels. Finally, we specify that the layout of groups must be preserved.

The interesting part is at the end. We must find the ContainerNode-s with the enums and interfaces and move them to the end of the diagram. Here is how:

        // Place enums and delegates at the end
        DiagramNode enums = diagram.findNode(":enums");
        DiagramNode delegates = diagram.findNode(":interfaces");

        double x = 0;
        //calculate the location of each node to find out the last one
        for (DiagramNode node : diagram.getNodes())
        {
        	if (node instanceof TableNode)
            {
        		x = Math.max(x, node.getBounds().getX() +  node.getBounds().getWidth());
            }
        }

        //move enums to the right of the last class node.
        if (enums != null)
        {
            enums.moveTo((float)x + 5f, (float)5);
            x = enums.getBounds().getX() + enums.getBounds().getWidth ();
        }

        if (delegates != null)
        {
            delegates.moveTo((float)x + 5, 5);
        } 

We cycle through each TableNode and always move the containers to the end of the rightmost TableNode that we find. Let’s not forget to resize the diagram after we are done:

 
diagram.resizeToFitItems(5);

With this our application is ready and we test it with an arbitrary *.jar file. Here is the result:

Class Diagram Application in Java

Class Diagram Application in Java

You can download the complete source code of the sample from here:

Download the Class Diagram Tool in Java Application

MindFusion support team welcomes your questions about the Java diagram library or any other of our programming tools at the discussion board or per e-mail at support@mindfusion.eu

About Diagramming for Java Swing: MindFusion.Diagramming for Java Swing provides your Java application with all necessary functionality to create and customize a diagram. The library is very easy to integrate and program. There are numerous utility methods, rich event set, more than 100 predefined shapes. The tool supports a variety of ways to render or export the diagram, advanced node types like TreeView nodes, hierarchical nodes, tables, container nodes and many more. There are 15 automatic layouts, various input / output options and fully customizable appearance. A detailed list with JDiagram’s features is uploaded here. You can check the online demo to see some of the functionality implemented.

Diagramming for Java Swing is royalty free, there are no distribution fees. Licenses depend on the count of developers using the tool – check here the prices.