Work in progress You can "draw" the GUI to the screen by writing Java code – alternatively to using XML. Typically you lay out the static base GUI in XML, and use Java commands if you need to change the GUI dynamically at runtime. In theory, you can also lay out the whole GUI in Java (but we don't cover that here).
Sample project
de.lessvoid.nifty.examples.controls.ControlsDemo.java
.assets/Interface/
directory. (In this example, I copied them from nifty-default-controls-examples/trunk/src/main/resources/
to assets/Interface/
).assets/
directory.filename("Interface/yang.png");
( not filename("yang.png");
).filename("Interface/sounds/gong.wav");
(not filename("sounds/gong.wav");
).Just so you get a quick picture what Nifty GUI's Java Syntax looks like, here is the most basic example. It creates a screen with a layer and a panel that contains a button.
package mygame;
import com.jme3.app.SimpleApplication;
import com.jme3.niftygui.NiftyJmeDisplay;
import de.lessvoid.nifty.Nifty;
import de.lessvoid.nifty.builder.ScreenBuilder;
import de.lessvoid.nifty.builder.LayerBuilder;
import de.lessvoid.nifty.builder.PanelBuilder;
import de.lessvoid.nifty.controls.button.builder.ButtonBuilder;
import de.lessvoid.nifty.screen.DefaultScreenController;
/**
* @author iamcreasy
*/
public class Main extends SimpleApplication {
public static void main(String[] args) {
Main app = new Main();
app.start();
}
@Override
public void simpleInitApp() {
NiftyJmeDisplay niftyDisplay = new NiftyJmeDisplay(
assetManager, inputManager, audioRenderer, guiViewPort);
Nifty nifty = niftyDisplay.getNifty();
guiViewPort.addProcessor(niftyDisplay);
flyCam.setDragToRotate(true);
nifty.loadStyleFile("nifty-default-styles.xml");
nifty.loadControlFile("nifty-default-controls.xml");
// <screen>
nifty.addScreen("Screen_ID", new ScreenBuilder("Hello Nifty Screen"){{
controller(new DefaultScreenController()); // Screen properties
// <layer>
layer(new LayerBuilder("Layer_ID") {{
childLayoutVertical(); // layer properties, add more...
// <panel>
panel(new PanelBuilder("Panel_ID") {{
childLayoutCenter(); // panel properties, add more...
// GUI elements
control(new ButtonBuilder("Button_ID", "Hello Nifty"){{
alignCenter();
valignCenter();
height("5%");
width("15%");
}});
//.. add more GUI elements here
}});
// </panel>
}});
// </layer>
}}.build(nifty));
// </screen>
nifty.gotoScreen("Screen_ID"); // start the screen
}
}
In this tutorial, you recreate the same screen as in the Nifty GUI XML example.
Create an Screen.Java file in the assets/Interfaces/
directory of your project. One Java file can contain several, or even all screens. As a reminder: Nifty displays one screen at a time; a screen contains several layers on top of one another; each layer contains panels that are embedded into another; the panels contain the actual content (text, images, or controls).
The following minimal Java file contains a start screen and a HUD screen. (Neither has been defined yet.)
nifty.addScreen("start", new ScreenBuilder("start"){{ controller(new DefaultScreenController()); // <!-- ... --> }}.build(nifty)); nifty.addScreen("hud", new ScreenBuilder("hud"){{ controller(new DefaultScreenController()); // <!-- ... --> }}.build(nifty));
Every Nifty GUI must have a start screen. The others (in this example, the HUD screen) are optional.
The following Java code shows how we add layers to the start screen and HUD screen:
nifty.addScreen("start", new ScreenBuilder("start"){{ controller(new DefaultScreenController()); // layer added layer(new LayerBuilder("background") {{ childLayoutCenter(); backgroundColor("#000f"); // <!-- ... --> }}); layer(new LayerBuilder("foreground") {{ childLayoutVertical(); backgroundColor("#0000"); // <!-- ... --> }}); // layer added }}.build(nifty));
Repeat the same, but use
nifty.addScreen("hud", new ScreenBuilder("hud"){{
for the HUD screen.
In a layer, you can now add panels and arrange them. Panels are containers that mark the areas where you want to display text, images, or controls (buttons etc) later.
A panel is the inner-most container (that will contain the actual content: text, images, or controls). You place panels inside layers. The following panels go into in the start
screen:
nifty.addScreen("start", new ScreenBuilder("start") {{ controller(new DefaultScreenController()); layer(new LayerBuilder("background") {{ childLayoutCenter(); backgroundColor("#000f"); // <!-- ... --> }}); layer(new LayerBuilder("foreground") {{ childLayoutVertical(); backgroundColor("#0000"); // panel added panel(new PanelBuilder("panel_top") {{ childLayoutCenter(); alignCenter(); backgroundColor("#f008"); height("25%"); width("75%"); }}); panel(new PanelBuilder("panel_mid") {{ childLayoutCenter(); alignCenter(); backgroundColor("#0f08"); height("50%"); width("75%"); }}); panel(new PanelBuilder("panel_bottom") {{ childLayoutHorizontal(); alignCenter(); backgroundColor("#00f8"); height("25%"); width("75%"); panel(new PanelBuilder("panel_bottom_left") {{ childLayoutCenter(); valignCenter(); backgroundColor("#44f8"); height("50%"); width("50%"); }}); panel(new PanelBuilder("panel_bottom_right") {{ childLayoutCenter(); valignCenter(); backgroundColor("#88f8"); height("50%"); width("50%"); }}); }}); // panel added }}); }}.build(nifty));
The following panels go into in the hud
screen:
nifty.addScreen("hud", new ScreenBuilder("hud") {{ controller(new DefaultScreenController()); layer(new LayerBuilder("background") {{ childLayoutCenter(); backgroundColor("#000f"); // <!-- ... --> }}); layer(new LayerBuilder("foreground") {{ childLayoutHorizontal(); backgroundColor("#0000"); // panel added panel(new PanelBuilder("panel_left") {{ childLayoutVertical(); backgroundColor("#0f08"); height("100%"); width("80%"); // <!-- spacer --> }}); panel(new PanelBuilder("panel_right") {{ childLayoutVertical(); backgroundColor("#00f8"); height("100%"); width("20%"); panel(new PanelBuilder("panel_top_right1") {{ childLayoutCenter(); backgroundColor("#00f8"); height("15%"); width("100%"); }}); panel(new PanelBuilder("panel_top_right2") {{ childLayoutCenter(); backgroundColor("#44f8"); height("15%"); width("100%"); }}); panel(new PanelBuilder("panel_bot_right") {{ childLayoutCenter(); valignCenter(); backgroundColor("#88f8"); height("70%"); width("100%"); }}); }}); // panel added }}); }}.build(nifty));
Try the sample. Remember to activate a screen using nifty.gotoScreen("start");
or hud
respectively.
The result should look as follows:
See also on the Nifty GUI site.
The start-background.png image is a fullscreen background picture. In the start
screen, add the following image element:
nifty.addScreen("start", new ScreenBuilder("start") {{ controller(new DefaultScreenController()); layer(new LayerBuilder("background") {{ childLayoutCenter(); backgroundColor("#000f"); // add image image(new ImageBuilder() {{ filename("Interface/tutorial/start-background.png"); }}); }});
The hud-frame.png image is a transparent frame that we use as HUD decoration. In the hud
screen, add the following image element:
nifty.addScreen("hud", new ScreenBuilder("hud") {{ controller(new DefaultScreenController()); layer(new LayerBuilder("background") {{ childLayoutCenter(); backgroundColor("#000f"); // add image image(new ImageBuilder() {{ filename("Interface/tutorial/hud-frame.png"); }}); }});
The face1.png image is an image that you want to use as a status icon.
In the hud
screen's foreground
layer, add the following image element:
panel(new PanelBuilder("panel_top_right2") {{ childLayoutCenter(); backgroundColor("#44f8"); height("15%"); width("100%"); // add image image(new ImageBuilder() {{ filename("Interface/tutorial/face1.png"); valignCenter(); alignCenter(); height("50%"); width("30%"); }}); }});
This image is scaled to use 50% of the height and 30% of the width of its container.
The game title is a typical example of static text. In the start
screen, add the following text element:
// panel added panel(new PanelBuilder("panel_top") {{ childLayoutCenter(); alignCenter(); backgroundColor("#f008"); height("25%"); width("75%"); // add text text(new TextBuilder() {{ text("My Cool Game"); font("Interface/Fonts/Default.fnt"); height("100%"); width("100%"); }}); }});
For longer pieces of static text, such as an introduction, you can use wrap="true". Add the following text element to the Start screen
:
panel(new PanelBuilder("panel_mid") {{ childLayoutCenter(); alignCenter(); backgroundColor("#0f08"); height("50%"); width("75%"); // add text text(new TextBuilder() {{ text("Here goes some text describing the game and the rules and stuff. "+ "Incidentally, the text is quite long and needs to wrap at the end of lines. "); font("Interface/Fonts/Default.fnt"); wrap(true); height("100%"); width("100%"); }}); }});
The font used is jME3's default font "Interface/Fonts/Default.fnt" which is included in the jMonkeyEngine.JAR. You can add your own fonts to your own assets/Interface
directory.
Before you can use any control, you must load a Control Definition first. Add the following two lines before your screen definitions:
nifty.loadStyleFile("nifty-default-styles.xml"); nifty.loadControlFile("nifty-default-controls.xml");
Use label controls for text that you want to edit dynamically from Java. One example for this is the score display.
In the hud
screen's foreground
layer, add the following text element:
panel(new PanelBuilder("panel_top_right1") {{ childLayoutCenter(); backgroundColor("#00f8"); height("15%"); width("100%"); control(new LabelBuilder(){{ color("#000"); text("123"); width("100%"); height("100%"); }});
Note that the width and height do not scale the bitmap font, but the make indirectly certain it is centered. If you want a different size for the font, you need to provide an extra bitmap font (they come with fixes sizes and don't scale well).
Our GUI plan asks for two buttons on the start screen. You add the Start and Quit buttons to the bottom panel of the start
screen using the <control>
element:
panel(new PanelBuilder("panel_bottom_left") {{ childLayoutCenter(); valignCenter(); backgroundColor("#44f8"); height("50%"); width("50%"); // add control control(new ButtonBuilder("StartButton", "Start") {{ alignCenter(); valignCenter(); height("50%"); width("50%"); }}); }}); panel(new PanelBuilder("panel_bottom_right") {{ childLayoutCenter(); valignCenter(); backgroundColor("#88f8"); height("50%"); width("50%"); // add control control(new ButtonBuilder("QuitButton", "Quit") {{ alignCenter(); valignCenter(); height("50%"); width("50%"); }}); }});
Note that these controls don't do anything yet – we'll get to that soon.
Nifty additionally offers many customizable controls such as check boxes, text fields, menus, chats, tabs, … See also on the Nifty GUI site.
When you preview this code in the jMonkeyEngine SDK, our tutorial demo should looks as follows: A start screen with two buttons, and a game screen with a simple HUD frame and a blue cube (which stands for any jME3 game content).
Tip: Remove all lines that set background colors, you only needed them to see the arrangement.
Before initializing the nifty screens, you set up properties and register media.
Nifty Method | Description |
---|---|
registerSound("mysound", "Interface/abc.wav"); | |
registerMusic("mymusic", "Interface/xyz.ogg"); | |
registerMouseCursor("mypointer", "Interface/abc.png", 5, 4); | |
registerEffect(?); | ? |
setDebugOptionPanelColors(true); | Highlight all panels, makes it easier to arrange them. |
Example:
nifty.registerMouseCursor("hand", "Interface/mouse-cursor-hand.png", 5, 4);
Integrate the GUI into the game. Typically, you will overlay the GUI.