public static TreeColumn createTreeColumn(Tree tree, int style, String text) {
TreeColumn column = new TreeColumn(tree, style);
column.setText(text);
return column;
}
public static void packColumns(@NotNull Tree tree, boolean fit, @Nullable float[] ratios) {
tree.setRedraw(false);
try {
// Check for disposed items
// TODO: it looks like SWT error. Sometimes tree items are disposed and NPE is thrown from
// column.pack
for (TreeItem item : tree.getItems()) {
if (item.isDisposed()) {
return;
}
}
int totalWidth = 0;
final TreeColumn[] columns = tree.getColumns();
for (TreeColumn column : columns) {
column.pack();
totalWidth += column.getWidth();
}
Rectangle clientArea = tree.getClientArea();
if (clientArea.isEmpty()) {
return;
}
if (fit) {
int areaWidth = clientArea.width;
if (tree.getVerticalBar() != null) {
areaWidth -= tree.getVerticalBar().getSize().x;
}
if (totalWidth > areaWidth) {
int extraSpace = totalWidth - areaWidth;
for (TreeColumn tc : columns) {
double ratio = (double) tc.getWidth() / totalWidth;
tc.setWidth((int) (tc.getWidth() - extraSpace * ratio));
}
} else if (totalWidth < areaWidth) {
float extraSpace = areaWidth - totalWidth;
if (columns.length > 0) {
if (ratios == null || ratios.length < columns.length) {
extraSpace /= columns.length;
extraSpace--;
for (TreeColumn tc : columns) {
tc.setWidth((int) (tc.getWidth() + extraSpace));
}
} else {
for (int i = 0; i < columns.length; i++) {
TreeColumn tc = columns[i];
tc.setWidth((int) (tc.getWidth() + extraSpace * ratios[i]));
}
}
}
}
}
} finally {
tree.setRedraw(true);
}
}
public static void main(String[] args) {
final Display display = new Display();
Shell shell = new Shell(display);
shell.setLayout(new FillLayout());
final Tree tree = new Tree(shell, SWT.FULL_SELECTION | SWT.BORDER);
tree.setHeaderVisible(true);
TreeColumn column0 = new TreeColumn(tree, SWT.LEFT);
column0.setText("Column 0");
TreeColumn column1 = new TreeColumn(tree, SWT.LEFT);
column1.setText("Column 1");
TreeColumn column2 = new TreeColumn(tree, SWT.LEFT);
column2.setText("Column 2");
for (int i = 0; i < 9; i++) {
TreeItem item = new TreeItem(tree, SWT.NONE);
item.setText("item " + i);
item.setText(1, "column 1 - " + i);
item.setText(2, "column 2 - " + i);
for (int j = 0; j < 9; j++) {
TreeItem subItem = new TreeItem(item, SWT.NONE);
subItem.setText("item " + i + " " + j);
subItem.setText(1, "column 1 - " + i + " " + j);
subItem.setText(2, "column 2 - " + i + " " + j);
for (int k = 0; k < 9; k++) {
TreeItem subsubItem = new TreeItem(subItem, SWT.NONE);
subsubItem.setText("item " + i + " " + j + " " + k);
subsubItem.setText(1, "column 1 - " + i + " " + j + " " + k);
subsubItem.setText(2, "column 2 - " + i + " " + j + " " + k);
}
}
}
column0.pack();
column1.pack();
column2.pack();
Heartbeat =
new Runnable() {
@Override
public void run() {
if (!Tracking || tree.isDisposed()) return;
Point cursor = display.getCursorLocation();
cursor = display.map(null, tree, cursor);
Scroll(tree, cursor.x, cursor.y);
display.timerExec(ScrollSpeed, Heartbeat);
}
};
Listener listener =
new Listener() {
@Override
public void handleEvent(Event event) {
switch (event.type) {
case SWT.MouseEnter:
Tracking = true;
display.timerExec(0, Heartbeat);
break;
case SWT.MouseExit:
Tracking = false;
break;
}
}
};
tree.addListener(SWT.MouseEnter, listener);
tree.addListener(SWT.MouseExit, listener);
shell.open();
while (!shell.isDisposed()) {
if (!display.readAndDispatch()) display.sleep();
}
display.dispose();
}