SDL_Joystick (sdl2gdx API)

java.lang.Object
- org.libsdl.SDL_Joystick

```
public final class SDL_Joystick
extends java.lang.Object
```
\file SDL_joystick.h
Include file for SDL joystick event handling
The term "device_index" identifies currently plugged in joystick devices between 0 and SDL_NumJoysticks(), with the exact joystick behind a device_index changing as joysticks are plugged and unplugged.
The term "instance_id" is the current instantiation of a joystick device in the system, if the joystick is removed and then re-inserted then it will get a new instance_id, instance_id's are monotonically increasing identifiers of a joystick plugged in.
The term JoystickGUID is a stable 128-bit identifier for a joystick device that does not change over time, it identifies class of the device (a X360 wired controller for example). This identifier is platform dependent.

In order to use these functions, SDL_Init() must have been called with the ::SDL_INIT_JOYSTICK flag. This causes SDL to scan the system for joysticks, and load appropriate drivers.
If you would like to receive joystick updates while the application is in the background, you should set the following hint before calling SDL_Init(): SDL_HINT_JOYSTICK_ALLOW_BACKGROUND_EVENTS

Field Summary

Fields
Modifier and Type	Field and Description
`float`	`AXIS_MAX`
`float`	`AXIS_MIN`
`SDL_JoystickID`	`instanceID` This is a unique ID for a joystick for the time it is connected to the system, and is never reused for the lifetime of the application.
`long`	`ptr`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`close()` Close a joystick previously opened with SDL_JoystickOpen().
`int`	`currentPowerLevel()` Return the battery level of this joystick SDL_JOYSTICK_POWER_UNKNOWN = -1, SDL_JOYSTICK_POWER_EMPTY = 0, SDL_JOYSTICK_POWER_LOW =1, SDL_JOYSTICK_POWER_MEDIUM =2, SDL_JOYSTICK_POWER_FULL =3, SDL_JOYSTICK_POWER_WIRED =4, SDL_JOYSTICK_POWER_MAX =5;
`boolean`	`equals(java.lang.Object o)`
`static boolean`	`eventStateEnable()`
`static boolean`	`eventStateIgnore()`
`static boolean`	`eventStateQuery()`
`boolean`	`getAttached()` Returns SDL_TRUE if the joystick has been opened and currently connected, or SDL_FALSE if it has not.
`float`	`getAxis(int axis)` Get the current state of an axis control on a joystick.
`boolean`	`getButton(int button)` Get the current state of a button on a joystick.
`int`	`getHat(int hat)` Get the current state of a POV hat on a joystick.
`java.lang.String`	`GUID()`
`int`	`hashCode()`
`SDL_JoystickID`	`instanceID()`
`static SDL_Joystick`	`joystickFromInstanceID(SDL_JoystickID joyid)`
`static java.lang.String`	`joystickNameForIndex(int device_index)` Get the implementation dependent name of a joystick.
`static SDL_Joystick`	`JoystickOpen(int i)`
`static void`	`joystickUpdate()` Update the current state of the open joysticks.
`java.lang.String`	`name()`
`int`	`numAxes()` Get the number of general axis controls on a joystick.
`int`	`numBalls()` Get the number of trackballs on a joystick.
`int`	`numButtons()` Get the number of buttons on a joystick.
`int`	`numHats()` Get the number of POV hats on a joystick.
`static int`	`numJoysticks()` Count the number of joysticks attached to the system right now
`static int`	`productVersion(int device_index)`
`boolean`	`rumble(float leftMagnitude, float rightMagnitude, int duration_ms)` Trigger a rumble effect Each call to this function cancels any previous rumble effect, and calling it with 0 intensity stops any rumbling.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ptr
```
public long ptr
```
  - AXIS_MIN
```
public final float AXIS_MIN
```
  - AXIS_MAX
```
public final float AXIS_MAX
```
  - instanceID
```
public final SDL_JoystickID instanceID
```
    This is a unique ID for a joystick for the time it is connected to the system, and is never reused for the lifetime of the application. If the joystick is disconnected and reconnected, it will get a new ID. The ID value starts at 0 and increments from there. The value -1 is an invalid ID.
- Method Detail
  - eventStateQuery
```
public static boolean eventStateQuery()
                               throws SDL_Error
```
    Throws:
    
    SDL_Error
  - eventStateIgnore
```
public static boolean eventStateIgnore()
                                throws SDL_Error
```
    Throws:
    
    SDL_Error
  - eventStateEnable
```
public static boolean eventStateEnable()
                                throws SDL_Error
```
    Throws:
    
    SDL_Error
  - joystickFromInstanceID
```
public static SDL_Joystick joystickFromInstanceID(SDL_JoystickID joyid)
```
  - joystickNameForIndex
```
public static java.lang.String joystickNameForIndex(int device_index)
```
    Get the implementation dependent name of a joystick. This can be called before any joysticks are opened. If no name can be found, this function returns NULL.
  - JoystickOpen
```
public static SDL_Joystick JoystickOpen(int i)
```
  - joystickUpdate
```
public static void joystickUpdate()
```
    Update the current state of the open joysticks. This is called automatically by the event loop if any joystick events are enabled.
  - numJoysticks
```
public static int numJoysticks()
                        throws SDL_Error
```
    Count the number of joysticks attached to the system right now
    
    Throws:
    
    SDL_Error
  - getAttached
```
public boolean getAttached()
```
    Returns SDL_TRUE if the joystick has been opened and currently connected, or SDL_FALSE if it has not.
  - getAxis
```
public float getAxis(int axis)
```
    Get the current state of an axis control on a joystick. The state is a value ranging from -1 to 1. The axis indices start at index 0.
  - getButton
```
public boolean getButton(int button)
```
    Get the current state of a button on a joystick. The button indices start at index 0.
  - currentPowerLevel
```
public int currentPowerLevel()
```
    Return the battery level of this joystick SDL_JOYSTICK_POWER_UNKNOWN = -1, SDL_JOYSTICK_POWER_EMPTY = 0, SDL_JOYSTICK_POWER_LOW =1, SDL_JOYSTICK_POWER_MEDIUM =2, SDL_JOYSTICK_POWER_FULL =3, SDL_JOYSTICK_POWER_WIRED =4, SDL_JOYSTICK_POWER_MAX =5;
  - getHat
```
public int getHat(int hat)
```
    Get the current state of a POV hat on a joystick. The hat indices start at index 0. \return The return value is one of the following positions: - ::SDL_HAT_CENTERED - ::SDL_HAT_UP - ::SDL_HAT_RIGHT - ::SDL_HAT_DOWN - ::SDL_HAT_LEFT - ::SDL_HAT_RIGHTUP - ::SDL_HAT_RIGHTDOWN - ::SDL_HAT_LEFTUP - ::SDL_HAT_LEFTDOWN
  - instanceID
```
public SDL_JoystickID instanceID()
```
  - name
```
public java.lang.String name()
```
  - numAxes
```
public int numAxes()
            throws SDL_Error
```
    Get the number of general axis controls on a joystick.
    
    Throws:
    
    SDL_Error
  - numButtons
```
public int numButtons()
               throws SDL_Error
```
    Get the number of buttons on a joystick.
    
    Throws:
    
    SDL_Error
  - numBalls
```
public int numBalls()
             throws SDL_Error
```
    Get the number of trackballs on a joystick. Joystick trackballs have only relative motion events associated with them and their state cannot be polled.
    
    Throws:
    
    SDL_Error
  - numHats
```
public int numHats()
            throws SDL_Error
```
    Get the number of POV hats on a joystick.
    
    Throws:
    
    SDL_Error
  - close
```
public void close()
```
    Close a joystick previously opened with SDL_JoystickOpen().
  - GUID
```
public java.lang.String GUID()
```
  - productVersion
```
public static int productVersion(int device_index)
```
  - rumble
```
public boolean rumble(float leftMagnitude,
                      float rightMagnitude,
                      int duration_ms)
```
    Trigger a rumble effect Each call to this function cancels any previous rumble effect, and calling it with 0 intensity stops any rumbling. \param joystick The joystick to vibrate \param low_frequency_rumble The intensity of the low frequency (left) rumble motor, from 0 to 1 \param high_frequency_rumble The intensity of the high frequency (right) rumble motor, from 0 to 1 \param duration_ms The duration of the rumble effect, in milliseconds \return 0, or -1 if rumble isn't supported on this joystick
  - equals
```
public boolean equals(java.lang.Object o)
```
    Overrides:
    
    equals in class java.lang.Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class java.lang.Object

Class SDL_Joystick

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ptr

AXIS_MIN

AXIS_MAX

instanceID

Method Detail

eventStateQuery

eventStateIgnore

eventStateEnable

joystickFromInstanceID

joystickNameForIndex

JoystickOpen

joystickUpdate

numJoysticks

getAttached

getAxis

getButton

currentPowerLevel

getHat

instanceID

name

numAxes

numButtons

numBalls

numHats

close

GUID

productVersion

rumble

equals

hashCode