Bug 501482

Summary:

Consider deprecation of CCombo

Product:

[Eclipse Project] Platform

Reporter:

Mickael Istria <mistria>

Component:

SWT

Assignee:

Platform-SWT-Inbox <platform-swt-inbox>

Status:

NEW ---

QA Contact:

Severity:

enhancement

Priority:

CC:

daniel_megert, karsten.thoms, psuzzi

Version:

4.6

Target Milestone:

---

Hardware:

All

OS:

All

Whiteboard:

Bug Depends on:

Bug Blocks:

501483

Attachments:

Description	Flags
Screenshot	none

Description Mickael Istria

2016-09-15 05:34:47 EDT

It would be worth investigating the feature gap between CCombo and regular Combo, and see whether:
1. there is none, so CCombo should be deprecated
2. there is some, but some CCombo feature could properly be ported to regular Combo, so we could plan a port of feature and then deprecate CCombo
3. There is a major one, and we should document it in Javadoc

Currently, CCombo doc says

"""
 * CCombo was written to work around certain limitations in the native
 * combo box. Specifically, on win32, the height of a CCombo can be set;
 * attempts to set the height of a Combo are ignored. CCombo can be used
 * anywhere that having the increased flexibility is more important than
 * getting native L&F, but the decision should not be taken lightly.
 * There is no is no strict requirement that CCombo look or behave
 * the same as the native combo box.
"""

Is this still true? Or did Combo receive the possiblity to set its height on all supported WS?

Comment 1 Karsten Thoms

2020-03-30 13:57:13 EDT

Created attachment 282276 [details]
Screenshot

I just stumbled over this as I was wondering why the height hint on a Combo did not have an effect. The desired height (29*scaling) was overruled by the computed height (24*scaling). (Display scaling was set to 200% in this case).

The controls look rather different. I doubt they could be brought together.

The place where this is overruled in Windows Combo is in
org.eclipse.swt.widgets.Combo.computeSizeInPixels(int, int, boolean)

	if (((style & SWT.SIMPLE) == 0) && OS.GetComboBoxInfo (handle, pcbi)) {
		width += pcbi.itemLeft + (pcbi.buttonRight - pcbi.buttonLeft);
		height = (pcbi.buttonBottom - pcbi.buttonTop) + pcbi.buttonTop * 2;

Maybe the height should be the Max(hHint,(pcbi.buttonBottom - pcbi.buttonTop) + pcbi.buttonTop * 2)?

Anyway, the docs are still valid, and we are speaking of similar but different controls.