I am creating a GUI of chat bot. I have made entire pane into BorderPane and allocated Vbox to Center pame to have chats. Now i want to have background wallpaper to chat, which means a background image to Vbox. But the problem with this is, i could only get background image to onle the extent where chat is present(i mean stack is present). Can someone suggest me what to do in order to have the picture in the background for the whole?
For example: right now, if i have only one message in the chat then the background image is occupying only the space till that chat and i am getting white screen in the below
As you wanted to I would set an ImageView behind the vbox or something like that.
So with that you can make the background transparent(VBox extends Node):
node.setStyle("-fx-background-color: transparent");
Then make it colorful with nearly the same command:
node.setStyle("-fx-background-color: #ffffff"); //white for example
OR:
node.setStyle("-fx-background-color: rgba(255, 255, 255, 0.7)"); //a bit white
Related
Can somebody tell me how I can make translucent and ungeometrically shaped (any custom shape except geometric shapes like rectangle for ex- cloud shaped window) window in java fx. I tried it by setting the png image to the background of AnchorPane using css, but the whole AnchorPane is showing rectangular.
So, I've been programming an analog clock in JavaFX and have gotten the base functionality down. Now, I'm trying to add a drop-down menu when I click a custom button (triangle made with a Polygon). So far it all works fine, except the fact that the background of my StackPane is white when I try to add a ContextMenu either before or after clicking the button. So far Transparency has been fine up until now. Here's some pictures of the issue.
This is what it should look like (you can see my wallpaper because of the transparent window, as it should be.)
enter image description here
After I press the button for the drop down menu, the background changes.
enter image description here
JavaFX controls are styled by CSS. The first time you create a control, the default user agent stylesheet (modena.css) is loaded and the styles defined in it are applied to the scene graph. Other JavaFX node classes, such as shapes, image views, and layout panes, do not enforce CSS loading (this is to enhance performance for graphically-intensive applications that do not need CSS).
So it sounds as though the context menu is the first control you create: when you create and display it, it will apply the default CSS to the scene. The default background color for the root pane is a non-transparent color, so while your Scene and Stage may be transparent, once the CSS is applied the scene's content is not.
The fix is to specify transparency for the root pane:
root.setStyle("-fx-background-color: transparent;");
or the equivalent in an external stylesheet.
To answer my own question in case anyone else wants to know, it seems that when the ContextMenu is added to the scene, the Stage's initStyle(StageStyle.TRANSPARENT) gets overridden and shows the Parent's colors. Since I didn't initialize any CSS styles for the root, it just showed white. The fix would be to:
//the Parent layout Pane
parent.setStyle("-fx-background-color: rgba(0, 0, 0, 0.0)");
I had a hard time figuring out why my transparent stage refuses to be transparent. Finally I found out, that it was caused by a Tooltip that was installed into an ImageView:
ImageView imageViewIcon = new ImageView();
imageViewIcon.setFitWidth(70);
imageViewIcon.setFitHeight(70);
imageViewIcon.setPreserveRatio(false);
imageViewIcon.setImage(new Image("./next.png"));
Tooltip tooltip = new Tooltip("Tooltip!");
if (this.config.getShowTooltip("true")) {
Tooltip.install(imageViewIcon, tooltip);
}
When I comment out the last 4 lines, the transparency works as expected, but with the Tooltip installed the stages background is grayish (e.g. the default window background). Though it's obvious what the button does and the tooltip is not essential for my layout it'd be nice to have, just to give a little hint...
Any suggestions or workarounds?
Solution
Set the style -fx-background-color: transparent on the root node of the scene.
Background
Similar behavior is discussed in an Oracle JavaFX Forum post on the JavaFX Scene/Fill Color.
Relevant comments from the thread by David Grieve, the lead developer for the JavaFX CSS features:
This happens because modena.css sets the background color of the root node. Setting the style -fx-background-color: transparent on the root node of the scene is the solution.
BorderPane root = new BorderPane();
root.setStyle("-fx-background-color: transparent;");
Scene scene = new Scene(root, 600, 400, Color.BLACK);
The default user agent stylesheet is loaded the first time a Control is instantiated. The reason for this is to avoid loading stylesheets and reduce CSS overhead in scene-graphs that contain nodes that don't use CSS.
The history behind it is that the designer of the modena theme felt that the controls looked better on this particular background color, which is a very light grey. Unfortunately, the Scene's background fill cannot be styled from CSS, so the style was set on the root node of the scene. There is an issue logged in JIRA to make Scene so that it can be styled by CSS (RT-31282)
The merit of loading in this way is to avoid css overhead in scene's that don't use controls. This would be typical of a splash screen, for example. Or maybe a game. This design choice was made a long time ago when CSS performance was a big issue, but it still makes sense for embedded devices.
In the case of your question, Tooltip is a control, so when you add it to the scene it implicitly triggers the default modena.css stylesheet to be loaded for the scene (which sets the background of the root node of the scene to gray rather than a null or transparent fill which is used when there are no controls in the scene). To retain the transparent background for the application when a control is used in the scene, it is necessary to explicitly set the scene root node background to transparent.
Sample code for a transparent stage:
//this is where the transparency is achieved:
//the three layers must be made transparent
//(i) make the VBox transparent (the 4th parameter is the alpha)
root.setStyle("-fx-background-color: rgba(0, 0, 0, 0);");
//(ii) set the scene fill to transparent
scene.setFill(null);
//(iii) set the stage background to transparent
stage.initStyle(TRANSPARENT);
I am building an App in which I had given background to my mainWindow only and all other widgets are used without any background, but when I run the app they are not 100% transparent they are somewhat translucent, is there any way to make them 100 % transparent so that only foreground can appear with no background hint.
Could you post the code you are using to get transparancy at the moment? If you say that you get "something translucent" I think that you created a tool window which is not what you really want.
A really transparent main window could be achieved by removing the title bar (give the QWidget constructor Qt::FramelessWindowHint as second parameter - WindowFlags), draw everything in the widget that should be transparent in a uncommon color (like 255,0,255) and then cut it off.
A very primitive example of cutting off parts of a QWidget:
QBitmap b(100, 100);
b.fill(Qt::black);
setMask(b);
QBitmap must be black on that pixels that shall be visible and white on that are not. In this example just the 100,100 area starting at 0,0 will be visible, the rest of your window will be invisible.
In my application I have an VBox control on top of another VBox that contains an Image control that loads a jpg from a URL (you can't see the bottom panel initially since it's underneath, but the image does fully download). When one clicks on the top VBox, the bottom one gets set to visible=false, then an effect causes the top VBox to vanish, then the bottom VBox is set to visible=true and an effect causes it to appear. Continuously clicking the VBoxes causes them to alternate appearing and disappearing. The problem is that the first time the bottom VBox appears, it flickers once when it draws. After that, there's no problem and it smoothly appears and disappears with the effect with no problem. It's as if the first time the bottom VBox appears, it flickers because even though the image has been downloaded, it has never been displayed before. Can I pre-buffer the image in the bottom VBox somehow to avoid this flicker?
See Ely Greenfield's demos # http://www.quietlyscheming.com/blog/2007/01/23/some-thoughts-on-doubt-on-flex-as-the-best-option-orhow-i-made-my-flex-images-stop-dancing/. Ely's the man.