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Horizontal scroll bar of a ScrolledComposite not visible

I read all old questions related to this issue but I didn't solve it.
Could someone helps me with this because I'm already run out of ideas.
Here is my code:
ScrolledComposite panelHolder = new ScrolledComposite(composite, SWT.H_SCROLL | SWT.V_SCROLL);
panelHolder.setLayout(new FillLayout());
panelHolder.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
FormToolkit toolkit = UIConstants.getToolkit();
toolkit.setBorderStyle(SWT.NONE);
tableViewer = new TableViewer(toolkit.createTable(panelHolder, border ? SWT.BORDER : SWT.NONE));
tableViewer.setContentProvider(new TableContentProvider());
ColumnViewerToolTipSupport.enableFor(tableViewer);
TableViewerColumn viewerColumn = new TableViewerColumn(tableViewer, SWT.NONE);
viewerColumn.setLabelProvider(labelProvider);
Table table = tableViewer.getTable();
table.setLinesVisible(false);
addControlListener(viewerColumn);
panelHolder.setContent(table);
panelHolder.setExpandHorizontal(true);
panelHolder.setExpandVertical(true);
panelHolder.setMinSize(table.computeSize(SWT.DEFAULT, SWT.DEFAULT));
panelHolder.layout();

Eclipse SWT ScrolledComposite refuses to scroll

I'm developing a plugin for eclipse and I'm struggling to use ScrolledComposite as well as making it take up the remaining space.
The parent layout is a 2-column Grid:
#Override
public void createPartControl(Composite parent) {
parent.setLayout(new GridLayout(2, false));
// other views etc
}
The ScrolledComposite is created like so (slightly abbreviated):
private void fillScroll() {
if (scroll != null) {
scroll.dispose();
}
scroll = new ScrolledComposite(parent, SWT.V_SCROLL | SWT.H_SCROLL | SWT.BORDER);
GridData gd = new GridData();
gd.horizontalSpan = 2;
scroll.setLayoutData(gd);
Composite innerContainer = new Composite(scroll, 0);
innerContainer.setLayout(new GridLayout(1, false));
// for loop that adds widgets to innerContainer
scroll.setExpandHorizontal(true);
scroll.setExpandVertical(true);
scroll.setContent(innerContainer);
scroll.setSize(innerContainer.computeSize(SWT.DEFAULT, SWT.DEFAULT));
parent.layout(true);
}
The list of questions are the widgets added in the for loop and are contained by innerContainer.
Expectation: Since innerContainer is too large to fit in the parent, there should be scroll bars.
What actually happens: There are no scroll bars.
How do I fix this problem?

The GridData on the ScrolledComposite needs to have grabExcessVerticalSpace set to true. I suggest you to use the extended constructor in order to clearly define how it should be displayed, for example:
GridData gd = new GridData(SWT.FILL, SWT.FILL, true, true, 2, 1);
Option A: change scroll.setSize to scroll.setMinSize:
scroll.setMinSize(innerContainer.computeSize(SWT.DEFAULT, SWT.DEFAULT));
or, Option B: remove scroll.setExpandHorizontal and scroll.setExpandVertical and change scroll.setSize to innerContainer.setSize:
innerContainer.setSize(innerContainer.computeSize(SWT.DEFAULT, SWT.DEFAULT));

Resize SWT Table

I have a wizard with table and button components. When I click to the add button I choose from dialog window what items should be added to the table. I confirm items, and then this ones appears in the table with scrollbar. But if I resize the wizard, the table size is changed. How to fix it?
Table before resize:
Table after wizard resize
Composite compositeArea = new Composite(parent, SWT.NONE);
GridLayout layout = new GridLayout();
layout.numColumns = 3;
compositeArea.setLayout(layout);
Table table = new Table(compositeArea, SWT.BORDER | SWT.V_SCROLL);
new TableColumn(someList, SWT.NULL);
table.setLayoutData(new GridData(HORIZONTAL_ALIGN_FILL | GRAB_HORIZONTAL));

** Please note that the use of HORIZONTAL_ALIGN_FILL and GRAB_HORIZONTAL is discouraged. Instead, you should be using the public GridData(int, int, boolean, boolean) constructor. **
To slighly simplify your code snippet (only one column on the composite, and only one default table column - see full code below):
// ...
final Composite compositeArea = new Composite(parent, SWT.NONE);
compositeArea.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
compositeArea.setLayout(new GridLayout());
final Table table = new Table(compositeArea, SWT.BORDER | SWT.V_SCROLL);
table.setLayoutData(new GridData(GridData.HORIZONTAL_ALIGN_FILL | GridData.GRAB_HORIZONTAL));
// ...
...and we see that the Table isn't fitting in the available space or showing the scrollbar as expected, and the same occurs when the Shell is resized.
In answer to your question, this is because the layout data of the Table doesn't know how to layout vertically - you've only specified two horizontal style attributes.
If we instead use the suggested constructor:
table.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
...the Table takes the available space correct, shows the scrollbar, and updates correctly when the Shell is resized. Using the layout data, we've told the Table to fill the available horizontal space, and the Table will display the scrollbar if necessary.
Full example:
public class TableResizeTest {
private final Display display;
private final Shell shell;
public TableResizeTest() {
display = new Display();
shell = new Shell(display);
shell.setLayout(new FillLayout());
shell.setMaximized(true);
final Composite parent = new Composite(shell, SWT.NONE);
parent.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
parent.setLayout(new GridLayout());
// -- snippet --
final Composite compositeArea = new Composite(parent, SWT.NONE);
compositeArea.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
compositeArea.setLayout(new GridLayout());
final Table table = new Table(compositeArea, SWT.BORDER | SWT.V_SCROLL);
// table.setLayoutData(new GridData(GridData.HORIZONTAL_ALIGN_FILL | GridData.GRAB_HORIZONTAL));
table.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
// -------------
for (int i = 0; i < 20; ++i) {
new TableItem(table, SWT.NONE).setText(String.valueOf(i));
}
}
public void run() {
shell.setSize(300, 300);
shell.open();
while (!shell.isDisposed()) {
if (display.readAndDispatch()) {
display.sleep();
}
}
display.dispose();
}
public static void main(final String... args) {
new TableResizeTest().run();
}
}

SWT GridLayout and GridData alignment of composite blocks

I understand that I have layout but I have problem with setting achivementsChild next to each other. I want to make some alignment or something similar. Now they are standing one below other and I want to set one next to the other.
TabItem tbtmStudent = new TabItem(tabFolder_1, SWT.NONE);
tbtmStudent.setText("Student");
ScrolledComposite scrolledComposite_1 = new ScrolledComposite(tabFolder_1, SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL);
scrolledComposite_1.addMouseWheelListener(new MouseWheelListener() {
public void mouseScrolled(MouseEvent e) {
scrolledComposite.setFocus();
}
});
tbtmStudent.setControl(scrolledComposite_1);
scrolledComposite_1.setExpandHorizontal(true);
scrolledComposite_1.setExpandVertical(true);
List<STUDENT> allSTUDENTNodes = currentData.getStudentNodes();
Composite studentChild = new Composite(scrolledComposite_1, SWT.NONE);
studentChild.setLayout(new GridLayout());
for(STUDENT studentNode: allSTUDENTNodes){
new STUDENTNode(studentChild, SWT.NONE, studentNode);
Composite achivementsChild = new Composite(scrolledComposite_1, SWT.DEFAULT);
achivementsChild.setLayout(new GridLayout());
for(Achivements achivementsNode: studentNode.getAchivements()){
new AchivementsNode(mscbcChild, SWT.NONE, achivementsNode);
}
}
scrolledComposite_1.setContent(studentChild);
scrolledComposite_1.setMinSize(studentChild.computeSize(SWT.DEFAULT, SWT.DEFAULT));

You can specify how many columns you want when you create the GridLayout:
new GridLayout(numberOfColumns, columnsEqual);
numberofColumns is the number of columns you want.
If columnsEqual is true all columns will have the same width, if it is false they will have their preferred size.

How to embed a SWT TableViewer in a TabFolder?

I am trying to embed a JFace TableViewer in a SWT TabFolder, but when I do so, the table does not show up. The current (working code) in my GitToDo code looks like (see this Git repos):
final Display display = new Display();
final Shell shell = new Shell(display);
shell.setText("Git ToDo");
FillLayout layout = new FillLayout();
shell.setLayout(layout);
final GitToDoTree tableViewer = new GitToDoTree(shell);
Where the latter GitToDoTree extends TableViewer, with this constructor:
super(parent, SWT.SINGLE | SWT.FULL_SELECTION | SWT.FILL);
this.shell = parent;
table = this.getTable();
table.setHeaderVisible(true);
table.setLinesVisible(true);
So, when I construct the TableViewer-extending GitToDoTree from a Shell it works, but as soon as I try to build it from a TabFolder or (tried that too) a Composite, nothing shows up anymore.
How can I get my TableViewer to show up in the TabFolder?

If your TableViewer class isn't showing up when you add it to a Composite I would say that chances are that you are not setting a layout for the nested Composite.
final Display display = new Display();
final Shell shell = new Shell(display);
shell.setText("Git ToDo");
FillLayout layout = new FillLayout();
shell.setLayout(layout);
Composite composite = new Composite(shell, SWT.NONE);
composite.setLayout(new FillLayout()); // Possible missing layout?
final GitToDoTree tableViewer = new GitToDoTree(composite);
And as for the TabFolder that may be that you are not setting the client control on the TabItem
TabFolder tabFolder = new TabFolder(shell, SWT.NONE);
TabItem item = new TabItem(tabFolder, SWT.NONE);
item.setText("Table");
GitToDoTree viewer = new GitToDoTree(tabFolder);
item.setControl(viewer.getTable()); // Possible setControl call?
TabItem item2= new TabItem(tabFolder, SWT.NONE);
item2.setText("Empty");