Vaadin
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The grid layout maintains a cursor for adding components in left-to-right, top-to-bottom order. If the cursor goes past the bottom-right corner, it will automatically extend the grid downwards by adding a new row.
The following example demonstrates the use of
// Create a 4 by 4 grid layout.
GridLayout grid = new GridLayout(4, 4);
grid.addStyleName("example-gridlayout");
// Fill out the first row using the cursor.
grid.addComponent(new Button("R/C 1"));
for (int i = 0; i < 3; i++) {
grid.addComponent(new Button("Col " + (grid.getCursorX() + 1)));
}
// Fill out the first column using coordinates.
for (int i = 1; i < 4; i++) {
grid.addComponent(new Button("Row " + i), 0, i);
}
// Add some components of various shapes.
grid.addComponent(new Button("3x1 button"), 1, 1, 3, 1);
grid.addComponent(new Label("1x2 cell"), 1, 2, 1, 3);
InlineDateField date = new InlineDateField("A 2x2 date field");
date.setResolution(DateField.RESOLUTION_DAY);
grid.addComponent(date, 2, 2, 3, 3);
The resulting layout will look as follows. The borders have been made visible to illustrate the layout cells.
A component to be placed on the grid must not overlap with existing
components. A conflict causes throwing a
You can define the size of both a grid layout and its components in either fixed or percentual units, or leave the size undefined altogether, as described in Section 5.3.9, “Sizing Components”. Section 6.10.1, “Layout Size” gives an introduction to sizing of layouts.
The size of the
The components contained within a A layout that contains components with percentual size must have a defined size!If a layout has undefined size and a contained component has, say, 100% size, the component would fill the space given by the layout, while the layout would shrink to fit the space taken by the component, which is a paradox. This requirement holds for height and width separately. The debug mode allows detecting such invalid cases; see Section 11.4.1, “Debug Mode”.
Often, you want to have one or more rows or columns that take all the
available space left over from non-expanding rows or columns. You need
to set the rows or columns as expanding with
GridLayout grid = new GridLayout(3,2);
// Layout containing relatively sized components must have
// a defined size, here is fixed size.
grid.setWidth("600px");
grid.setHeight("200px");
// Add some content
String labels [] = {
"Shrinking column<br/>Shrinking row",
"Expanding column (1:)<br/>Shrinking row",
"Expanding column (5:)<br/>Shrinking row",
"Shrinking column<br/>Expanding row",
"Expanding column (1:)<br/>Expanding row",
"Expanding column (5:)<br/>Expanding row"
};
for (int i=0; i<labels.length; i++) {
Label label = new Label(labels[i], Label.CONTENT_XHTML);
label.setWidth(null); // Set width as undefined
grid.addComponent(label);
}
// Set different expansion ratios for the two columns
grid.setColumnExpandRatio(1, 1);
grid.setColumnExpandRatio(2, 5);
// Set the bottom row to expand
grid.setRowExpandRatio(1, 1);
// Align and size the labels.
for (int col=0; col<grid.getColumns(); col++) {
for (int row=0; row<grid.getRows(); row++) {
Component c = grid.getComponent(col, row);
grid.setComponentAlignment(c, Alignment.TOP_CENTER);
// Make the labels high to illustrate the empty
// horizontal space.
if (col != 0 || row != 0)
c.setHeight("100%");
}
}
If the size of the contained components is undefined or fixed, the
expansion ratio is of the excess space, as in
Figure 6.4, “Expanding Rows and Columns in .v-gridlayout {}
.v-gridlayout-margin {}
The v-gridlayout is the root element of the
For styling the individual grid cells, you should style the components
inserted in the cells. The implementation structure of the grid can
change, so depending on it, as is done in the example below, is not
generally recommended. Normally, if you want to have, for example, a
different color for a certain cell, just make set the component inside
it
The following example shows how to make the grid borders visible, as
in Figure 6.4, “Expanding Rows and Columns in .v-gridlayout-gridexpandratio {
background: blue; /* Creates a "border" around the grid. */
margin: 10px; /* Empty space around the layout. */
}
/* Add padding through which the background color shows. */
.v-gridlayout-gridexpandratio .v-gridlayout-margin {
padding: 2px;
}
/* Add cell borders and make the cell backgrounds white.
* Warning: This depends heavily on the HTML structure. */
.v-gridlayout-gridexpandratio > div > div > div {
padding: 2px; /* Layout background will show through. */
background: white; /* The cells will be colored white. */
}
/* Components inside the layout are a safe way to style cells. */
.v-gridlayout-gridexpandratio .v-label {
text-align: left;
background: #ffffc0; /* Pale yellow */
}
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