{"id":442,"date":"2012-09-04T14:26:26","date_gmt":"2012-09-04T08:56:26","guid":{"rendered":"http:\/\/ramkulkarni.com\/blog\/?p=442"},"modified":"2012-09-04T14:26:26","modified_gmt":"2012-09-04T08:56:26","slug":"eclipse-swt-gridlayout-making-the-widget-fill-horizontally","status":"publish","type":"post","link":"http:\/\/ramkulkarni.com\/blog\/eclipse-swt-gridlayout-making-the-widget-fill-horizontally\/","title":{"rendered":"Eclipse SWT GridLayout – Making the widget fill horizontally"},"content":{"rendered":"

I have been stuck with the problem of making UI widgets fill horizontally in a grid layout a few times. The solution is simple, but when I have to create UI using Eclipse SWT after a long gap, I tend to forget how I had made this work earlier, so I decided to blog about this.<\/p>\n

I had to create a simple UI with one label and associated text box. I coded it like this –<\/p>\n

GridLayout layout = new GridLayout(2, false);<\/span>\ntabContainer.setLayout(layout);<\/span> \/\/this is the parent composite<\/span>\n\nLabel label1 = new Label(tabContainer, SWT.NONE);<\/span>\nlabel1.setText(\"Some Label:\");<\/span>\nGridData gd = new GridData();<\/span>\ngd.grabExcessHorizontalSpace = false;<\/span>\nlabel1.setLayoutData(gd);<\/span>\n\nText txtBox1 = new Text(tabContainer, SWT.BORDER);<\/span>\ngd = new GridData();<\/span>\ngd.grabExcessHorizontalSpace = true;<\/span>\ntxtBox1.setLayoutData(gd);<\/span><\/pre>\n
<\/p>\n
UI created by the above code is –<\/p>\n
\"\"<\/a><\/p>\n
With grabExcessHorizontalSpace attribute of GridData set to true, I was expecting text box to fill the horizontal space. JavaDoc for this attribute says – “grabExcessHorizontalSpace specifies whether the width of the cell changes depending on the size of the parent Composite”. So I thought it should be enough to make text box fill horizontal space. But it did not.<\/p>\n
After digging into previously written code for similar UI, I found that I had to set another attribute to make it work. I had to set gd.horizontalAlignment = SWT.FILL;<\/p>\n
Text txtBox1 = new Text(tabContainer, SWT.BORDER);<\/span>\ngd = new GridData();<\/span>\ngd.grabExcessHorizontalSpace = true;<\/span>\ngd.horizontalAlignment = SWT.FILL;<\/span>\ntxtBox1.setLayoutData(gd);<\/span><\/pre>\n
The above change generated the UI that I was expecting –<\/p>\n
\"\"<\/a><\/p>\n
I think name ‘horizontalAlignment’ is confusing – JavaDoc says : “horizontalAlignment specifies how controls will be positioned horizontally within a cell. The default value is BEGINNING”. So you might think that this attribute controls position of the widget in the cell, but it also has a value that controls its size (SWT.FILL).<\/p>\n
Note that both the attributes,\u00a0grabExcessHorizontalSpace and horizontalAlignment, have to be set to make this work.<\/p>\n
So next time I face the same problem, I will remember to refer to this post.<\/p>\n
-Ram Kulkarni<\/p>\n","protected":false},"excerpt":{"rendered":"
I have been stuck with the problem of making UI widgets fill horizontally in a grid layout a few times. The solution is simple, but when I have to create UI using Eclipse SWT after a long gap, I tend to forget how I had made this work earlier, so I decided to blog about … <\/p>\n
Continue reading “Eclipse SWT GridLayout – Making the widget fill horizontally”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false}}},"categories":[38,1],"tags":[25,47,48,49],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2g9O8-78","jetpack-related-posts":[],"_links":{"self":[{"href":"http:\/\/ramkulkarni.com\/blog\/wp-json\/wp\/v2\/posts\/442"}],"collection":[{"href":"http:\/\/ramkulkarni.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/ramkulkarni.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/ramkulkarni.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/ramkulkarni.com\/blog\/wp-json\/wp\/v2\/comments?post=442"}],"version-history":[{"count":0,"href":"http:\/\/ramkulkarni.com\/blog\/wp-json\/wp\/v2\/posts\/442\/revisions"}],"wp:attachment":[{"href":"http:\/\/ramkulkarni.com\/blog\/wp-json\/wp\/v2\/media?parent=442"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/ramkulkarni.com\/blog\/wp-json\/wp\/v2\/categories?post=442"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/ramkulkarni.com\/blog\/wp-json\/wp\/v2\/tags?post=442"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}