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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If a component’s display area is larger than the component itself, then you can specify whereabouts in the display area the gridbaglyaout will be displayed by using the GridBagConstraints. A real figure will go here.
Remember that you can do a lot with nested panels and by composing simpler layout managers within one another. The value is specified as an Insets object. LayoutManagerLayoutManager2Serializable public class GridBagLayout extends Object implements LayoutManager2Serializable The GridBagLayout class is a flexible layout manager that aligns components vertically, horizontally or along their baseline without requiring that the components be of the same size.
The width of the component will be at least its minimum width plus ipadx pixels. Because the second button and the panel share the same prevailing row, they are both aligned along their baseline.
Now that you know the basics, and have the abstract view needed to design Frames using the GridBagLayout, let’s see how to use it for your layout. Retrieves the constraints for the specified component. Similarly, each row’s weight is related to the highest weighty specified for a component within that row.
Fill the available space in both directions. Controls the number of rows or columns the component spans. Positions five components within a container, using weights, fill, and geidbaglayout positioning.
Learning Java, 4th Edition by Daniel Leuck, Patrick Niemeyer
Its code is in GridBagLayoutDemo. Determine which cells the components occupy. GridBagLayoutInfo info This method is obsolete and supplied for backwards compatability only; new code should call getMinSize instead. The gory details of the calculations follow.
GridBagLayout tries to calculate an effective weight for the portion of the component that occupies each row or column. Resizable components positioned above the baseline can only grow as tall as the baseline. GridBagLayout is a Layout Managerand one of the most complex managers.
GridBagLayout (Java Platform SE 7 )
In this way, you can control how various components will grow and stretch when a window is resized. Previous releases require values named after points of the compass.
A GridBagLayout places components in a grid of rows and columns, allowing specified components to span multiple rows or columns. This behavior is also specified by the program. The preferred approach to set constraints on a component is to use the Container. Note that if you enlarge the window, the last row is the only one that gets taller. Gridhaglayout positioned using one of the baseline-relative values resize differently than when positioned using an absolute or orientation-relative value.
Current implementation doesn’t impose any limits on the size of a grid.
GridBagLayout – Learning Java, 4th Edition [Book]
This method is the same as getLayoutInfo ; refer to getLayoutInfo for details on parameters and return value. Unless you specify a weight for at least one component in a row weightx and column weightyall the components clump together in the center of their container. The West button is unnaturally tall, which means that the middle row of the layout must be taller than the others.
All the added objects behind the anchor will be affected by it, be conscious of that.
The overall orientation of the grid depends on the container’s ComponentOrientation property. 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.
The layout manager does it automatically as you add components. This is because only button 5 has weighty javaa than zero. Create the following Java program using any editor of your choice in say D: The following code is typical of what goes in a container that uses a GridBagLayout.
Larger numbers indicate that the component’s row or column should get more space. A GridBagLayout places components in a grid of rows and columns, allowing specified components to span multiple rows or columns. The next section discusses constraints in depth, in the context of explaining how the example program works. Weights are used to calculate how much a given column or row stretches beyond its preferred size, if the layout has extra room to fill.
Adjusts the x, y width and height fields to the correct values depending on the constraint geometry and pads. Aligns two pairs of labels and text fields, plus adds a label across the full width of the container.