GridBagLayout is one of the most flexible — and complex — layout managers the Java platform provides. A GridBagLayout places components in a grid of rows. Following is the declaration for gLayout class − public class GridBagLayout extends Object implements LayoutManager2, Serializable. Component; import ner; import gConstraints; import gLayout; import ; import JButton.
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The first and last rows of buttons motivate the use of multiple GridBagLayout containers, each with its own grid. One of the most important features of GridBaglayout is that it lets you create arrangements in which components span two or more rows or columns. How to Write a Container Listener. This function is used for extending the object to the gridsize, and it is very useful when your Windows is resizable. I prefer not using them. The next section discusses constraints in depth, in the context of explaining how the example program works.
Specifying Constraints The following code is typical of what goes in a container that uses a GridBagLayout.
However, it makes it easier to see exactly how much space each button occupies. This is because when the weight is 0. You can set the following GridBagConstraints instance variables: A GridBagLayout places components in a grid of rows gridbaglaykut columns, allowing specified components to span multiple rows or columns. Instead, describe the problem and what has been done so far to solve it. The situation is a bit more complicated when there are multiple rows or columns and when there is even the possibility of components spanning more than one cell.
Setting either of these to the constant REMAINDER says gridbaglauout the component should be the last item in its row or column and, therefore, should occupy all the remaining space. Similarly if you have positioned a component relative to the baseline and none of the components in the row have a valid baseline the component is vertically centered. This method is obsolete and supplied for backwards compatability only; new code should call getMinSize instead.
Take note of how they’re organized.
Gridx and Gridy are always 0 by default. You can find the entire source file in GridBagLayoutDemo.
Dimension maximumLayoutSize Container target Returns the maximum dimensions for this layout given the components in the specified target container. Values that are different from those in the previous table entry are marked in italics. If you are not interested in learning all the details of layout management, you might prefer to use the GroupLayout layout manager javz with a builder tool to lay out your GUI.
This is because only button 5 has weighty greater than zero. Returns the maximum dimensions for this layout given the components in the specified target container.
It’s especially good if you want to avoid large piles of code when you’re adding objects to your container, now you can add one object in one line. We will use three grid bag layouts: This requires three passes through the set of children: The next section discusses constraints in depth, in the context of explaining how the example program works. So first of all, you gridgaglayout need to understand what is GridBagLayout. In addition to its constraints object, the GridBagLayout also considers each component’s minimum and preferred sizes in order to determine a component’s size.
You’ll see a more detailed example in the next section.
Using GridBagConstraints : GridBagConstraints « Swing « Java Tutorial
Create the following Java program using any editor of your choice in say D: This means that the Calculator must register as a ContainerListener for itself and for the two panels, topRow and bottomRow. If the program didn’t specify the fill, the buttons would be at their natural width, like this: GridbagLayout wants to evaluate them to see whether they affect the determination of the largest weight in a row or column.
Determines the origin of the layout area, in the graphics coordinate space of the target container. Here is a picture of how these values are interpreted in a container that has the default, left-to-right component orientation.
If this field is non- null the values are applied to the gridbag after all of the minimum row heights have been calculated.
Fills in an instance of GridBagLayoutInfo for the current set of managed children. The way to create your GridBagConstraints is shown below: This is a simple and problem-free way to achieve relative placement.
In this example, we set the fill to BOTH and weightx and weighty to 1 for all components. Lays out the specified container using this grid bag layout.
GridBagLayout – Learning Java, 4th Edition [Book]
A GridBagLayout places components in a grid of rows and columns, allowing specified components to span multiple rows or columns. Note that if you enlarge the window, the last row is the only one that gets taller. All of this referring to Excel of course.
This gridbaglzyout is no longer used to reserve arrays and keeped for backward compatibility. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more. Extra space tends to go toward the rightmost column and bottom row.
Padding and weighting have an odd interaction with each other. Individual components may also be told to span more than one row or column. We said earlier that three layout managers are in our user interface: For each column, the weight is related to the highest weightx specified for a component within that column, with each multicolumn component’s weight being split somehow between the columns gridbaglaout component is in.
The following figure shows the grid for the preceding applet. The following table lists gridbaglaayout few. As you can see, the grid has three rows and three columns.