How to insert Image into Column Header of CellTable (GWT)? - gwt

If we use Text for the header then it may take some space, so I want the Header have an icon(like Delete Icon) so I can save some space for the Header.
I tried
myCellTable.addColumn(deleteColumn,new SafeHtmlHeader(SafeHtmlUtils.fromSafeConstant
("<img width=\"30px\" height=\"30px\" src=\"image/icon/delete.png\">")));
It showed the image but the Image is very small about (10px - 10px) and it has a ugly border around the image.
SOmeone said using CUstom Header, but I couldn't override getHeaderStyleNames(). Ex:
class DeleteHeader extends Header{
#Override
public String getHeaderStyleNames(){
return "css style";
}
}
It said i have to override supertype something....!!
So how to fix it?

Try this:
header.setHeaderStyleNames("deleteHeader");
Do not render image in this header. You can use a standard TextHeader, for example.
In CSS define this style with image as a background.

Related

How to user custom Drag Appearance in smart gwt

I am trying to user Custom Drag appearance in smart gwt. how can i implement it.
Current when using DragAppearance.TRACKER its show on 10px square i want a lable with caption Drag to Lineup.
vLayout1.setDragAppearance(DragAppearance.TRACKER);
vLayout1.setCanHover(true);
vLayout1.setCursor(Cursor.HAND);
I hope, the following links will help you
https://github.com/moravianlibrary/MEditor/blob/master/editor-editation/src/main/java/cz/mzk/editor/client/view/ModifyView.java#L1100:L1104
https://github.com/moravianlibrary/MEditor/blob/master/editor-common/editor-common-client/src/main/java/cz/mzk/editor/client/view/other/EditorDragMoveHandler.java
Override BaseWidget.setDragTracker and provide required content using EventHandler.setDragTracker.
VLayout vLayout1 = new VLayout() {
#Override
protected boolean setDragTracker() {
EventHandler.setDragTracker("<pre>Drag to Lineup</pre>");
return false;
}
};
vLayout1.setCanDrop(true);
vLayout1.setCanDrag(true);
vLayout1.setDragAppearance(DragAppearance.TRACKER);
EventHandler.setDragTracker accepts any valid html code and <pre/> tags were used above to avoid word wrap.
Check following sample in SmartGWT showcase:
http://www.smartclient.com/smartgwt/showcase/#effects_dd_tracker

GWT: How to dynamically load a new image?

I want to fetch an image from a remote server (not my app's server, but I don't think that matters) and display it in an existing Image widget. The existing widget displays its original content, from a ClientBundle ImageResource , OK.
In UiBinder template:
<g:Image ui:field='myImage' resource='{res.anImage}'/>
In code:
#UiField Image myImage;
...
int width = Window.getClientWidth();
int height = Window.getClientHeight();
String url = ...;
myImage.addErrorHandler(new ErrorHandler() {
public void onError(ErrorEvent event) {
Window.alert("Error getting image data: " + event);
}
});
myImage.addLoadHandler(new LoadHandler() {
public void onLoad(LoadEvent event) {
Window.alert("LoadEvent: " + event);
}
});
myImage.setUrlAndVisibleRect(url, 0, 0, width, height);
As far as I can tell setUrlAndVisibleRect is a no-op. FireBug reports no network activity -- no request to the server specified by the URL. What am I overlooking? In my extended thrashing about trying to get this working I have inferred that it may have something to do with myImage not being "logically attached", but I'm not entirely sure what that means and I've no idea how to correct it if that is the problem.
EDIT with SUMMARY of SOLUTION:
My initial hunch was right. Because I had chosen to implement the image code within a second pseudo-widget (...extends Composite) that shared my UiBinder template with the main pseudo-widget that implements most of my app's UI, I got into trouble. I neglected to add this second pseudo-widget to the RootPanel as is normally done in the class that implements EntryPoint. This left my Image widget unattached to the widget chain, because its parent, the second pseudo-widget, was unattached. And an Image widget must be attached to work. What I ended up doing is moving the Image code back into my main app/GUI class, i.e., into the first and now only pseudo-widget and abandoning the special class for the Image code. I did that because it's simpler and the Image code turns out not to be as long as I had originally thought.
Adding image to the DOM is little tricky,the below code which supports all the browsers(setVisibility trick added to support IE also,as It has a different way to image rendering).
I did'nt use setUrlAndVisibleRect before and AFAIK,Image must render to the DOM inorder to resize it.Just try the below codes.
image.addLoadHandler(new LoadHandler() {
#Override
public void onLoad(LoadEvent event) {
//Do your operations on image .//resize ..etc
image.getElement().getStyle().setVisibility
(Style.Visibility.Visible);
}
});
image.getElement().getStyle().setVisibility(Style.Visibility.HIDDEN);
RootPanel.get().add(image);
image.setUrl(url);
You are using ClientBundle ImageResource which is compile time. You cannot change it unless you replace the new image with exact name in the exact position of prev one. One of the possible hack which is possible is, place the image in a div with its ID set ( getElement().setId("your ID") ). Once you get you new image you use RootPanel.get("Your Id") and do your job.

centering the contents of an column in GWT Bootstrap cell table

I have an cell table and the column data are the check boxes i want align these check boxes to center of that column
i tried withcolumn.setHorizontalAlignment(HasHorizontalAlignment.ALIGN_CENTER);
and using text-align:middle in css. but it doesn't seem to work .Please help
Column<Person, Boolean> checkColumn = new Column<Person, Boolean>(
new CheckboxCell(true, false)) {
#Override
public Boolean getValue(Person object) {
// check box function
}
};
checkColumn.setHorizontalAlignment(HasAlignment.ALIGN_CENTER);
Works fine for me.
Since you didn't provide much code I can only make several assumptions:
Check that your cell table CSS [if your using custom ones] isn't over writing the alignment
Double check your aligning the right column [happens]
If you are using UiBinder, check to make sure you only set alignment in either your java class or the xml

GWT: TabLayoutPanel with custom tabs does not display correctly

I have a TabLayoutPanel where I am putting custom widgets in for the tabs to be able to display some images next to the text. I originally worked with TabPanel and using custom HTML for the tab text, but custom tab widgets allows me to modify the image on the fly as needed.
My tab widget is essentially a HorizontalPanel, a number of small images, and a line of text. The problem I'm having is that the tab doesn't want to stick to the bottom of the tab bar like normal. The tab is getting positioned at the top of the space reserved for the tab bar, and there's a gap between it and the bottom of the tab bar. I uploaded an image of the problem to http://imgur.com/fkSHd.jpg.
Is there some style that I need to apply to custom widget tabs to make them appear correctly?
In my brief experience, the newer standards mode panels (they all end in "LayoutPanel") don't get along with the older ones (the ones that just end in "Panel"). So you might consider trying a DockLayoutPanel instead of the HorizontalPanel, and it may be more cooperative.
See https://developers.google.com/web-toolkit/doc/latest/DevGuideUiPanels, particularly the section called "What won't work in Standards Mode?":
HorizontalPanel is a bit trickier. In some cases, you can simply
replace it with a DockLayoutPanel, but that requires that you specify
its childrens' widths explicitly. The most common alternative is to
use FlowPanel, and to use the float: left; CSS property on its
children. And of course, you can continue to use HorizontalPanel
itself, as long as you take the caveats above into account.
After a bit more research, I found the answer here: https://groups.google.com/d/msg/google-web-toolkit/mq7BuDaTNgk/wLqPm5MQeicJ. I had to use InlineLabel or InlineHTML widgets instead of normal Label or HTML widgets. I've tested this solution and it does exactly what I want. I pasted the code of the class below for completeness. Note two things here:
The "float" attribute cannot be set on the last element (the InlineLabel) or the incorrect drawing condition occurs again.
The code could be cleaned up a bit further by having the class extend directly from FlowPanel instead of making it a composite containing a FlowPanel.
package com.whatever;
import com.google.gwt.core.client.GWT;
import com.google.gwt.dom.client.Style.Float;
import com.google.gwt.dom.client.Style.Unit;
import com.google.gwt.resources.client.ClientBundle;
import com.google.gwt.resources.client.ImageResource;
import com.google.gwt.user.client.ui.Composite;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.Image;
import com.google.gwt.user.client.ui.InlineLabel;
public class StatusTab extends Composite
{
public interface StatusImages extends ClientBundle
{
public static StatusImages instance = GWT.create(StatusImages.class);
#Source("images/status-green.png")
ImageResource green();
#Source("images/status-red.png")
ImageResource red();
}
private final ImageResource greenImage;
private final ImageResource redImage;
private final FlowPanel flowPanel;
public LinkStatusTab(String text, int numStatuses) {
greenImage = StatusImages.instance.green();
redImage = StatusImages.instance.red();
flowPanel = new FlowPanel();
initWidget(flowPanel);
for (int i = 0; i < numStatuses; i++)
{
Image statusImg = new Image(redImage);
statusImg.getElement().getStyle().setMarginRight(3, Unit.PX);
statusImg.getElement().getStyle().setFloat(Float.LEFT);
flowPanel.add(statusImg);
}
flowPanel.add(new InlineLabel(text));
}
/**
* Sets the image displayed for a specific status entry.
*/
public void setStatus(int which, boolean status)
{
Image image = (Image)flowPanel.getWidget(which);
if (status)
image.setResource(greenImage);
else
image.setResource(redImage);
}
}

Gtk Button inner-border

I add a button to HBox, with expand equal to False, but I want the button to have more spacing between its label and border. I assume it is "inner-border" property, but it is read-only. How can I set it to e.g. 4px?
gtk.Label is a subclass of gtk.Misc which has the method set_padding. If you get the label out of the gtk.Button then you can just call set_padding on it.
You could do something like:
label = gtk.Label("Hello World")
button = gtk.Button()
/* Add 10 pixels border around the label */
label.set_padding(10, 10)
/* Add the label to the button */
button.add(label)
/* Show the label as the button will assume it is already shown */
label.show()
Wrong answer:
What you're looking for is called "padding". When you add your button to the container, for example by calling gtk.Box.pack_start, just set the padding parameter to a positive integer.
Update:
Seems I misread the question. In that case, my guess is that you're supposed to use gtk_widget_modify_style, as inner-border is a style property. You'll first get the style modifier you need by calling gtk_widget_get_modifier_style. You'll then be able to modify the style only for that button using the ressource styles matching rules.
you can use "inner-border" style property of gtk button.
here, small code snippets
In gtkrc file:
style "button_style"
{
GtkButton::inner-border = {10,10,10,10}
}
class "GtkButton" style "button_style"
In .py file:
gtk.rc_parse(rc_file_path + rc_file)
[Edit]
In gtkrc file:
style "button_style"
{
GtkButton::inner-border = {10,10,10,10}
}
widget "*.StyleButton" style "button_style" # apply style for specific name of widget
In .py file:
gtk.rc_parse(rc_file_path + rc_file)
#set name of button
self.style_button.set_name('StyleButton')
hope, it would be helpful.
I sometimes just add spaces in the label !
gtk.Button(" Label ")
to get some spacing.
Hope this could help you.