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QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
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Gestures Library Reference
The Gestures library provides gesture recognizers to detect gestures through touch events that occur when you place one or more fingers on a touch screen.
Gestures Library Reference
The Gestures library primarily provides gesture recognizers to detect gestures through mtouch events that occur when you place one or more fingers on a touch screen.
double_tap.h
Definition of the double tap gesture.
double_tap_params_t
Double tap gesture parameters

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
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  - Gestures Library Reference
    The Gestures library provides gesture recognizers to detect gestures through touch events that occur when you place one or more fingers on a touch screen.
    - Gestures Library Overview
      The Gestures library provides gesture recognizers to detect gestures through touch events that occur when you place one or more fingers on a touch screen.
    - Gesture Recognition
      Gesture recognition is performed by gesture recognizers that detect gestures through touch events.
    - Custom Gestures
      You can define gesture recognizers to detect gestures that are not already supported by the Gestures library (custom gestures). Gesture recognizers that are used to detect custom gestures can be compiled with the application code and added to a gesture set in the same way that system gesture recognizers are added to a gesture set.
    - Gesture Tutorials
      Gestures tutorials aim to help you understand how to use the Gestures library in your own applications by providing step-by-step guides.
    - Gestures Library Reference
      The Gestures library primarily provides gesture recognizers to detect gestures through mtouch events that occur when you place one or more fingers on a touch screen.
      - bucket.h
        Data types and functions for gesture buckets.
      - defaults.h
        Global settings for gesture timings.
      - double_tap.h
        Definition of the double tap gesture.
        double_tap_gesture_alloc()
        Allocate and initialize the double tap gesture structure
        double_tap_gesture_default_params()
        Initialize the double tap parameters
        double_tap_params_t
        Double tap gesture parameters
        double_tap_state_e
        States for the double tap gesture
        gesture_double_tap_t
        The double tap gesture data type
      - event_list.h
        Data types and functions for event lists.
      - long_press.h
        Definition of the long press gesture.
      - pinch.h
        Definition of the pinch gesture.
      - press_and_tap.h
        Definition of the press and tap gesture.
      - rotate.h
        Definition of the rotate gesture.
      - set.h
        Data types and functions for gesture sets.
      - swipe.h
        Definition of the swipe gesture.
      - tap.h
        Definition of the tap gesture.
      - timer.h
        Functions and datatypes for gestures timers.
      - triple_tap.h
        Definition of the triple tap gesture.
      - two_finger_pan.h
        Definition of the two finger pan gesture.
      - two_finger_tap.h
        Definition of the two finger tap gesture.
      - two_finger_double_tap.h
        Definition of the double tap gesture.
      - types.h
        Common data types and helper functions.
  - Image Library Reference
  - Input Events Library Reference
    The Input Events library provides the framework necessary for Screen Graphics Subsystem to communicate with your touch driver.
  - OpenWF Configuration Developer's Guide
    If you are integrating a new display, you must configure and provide the parameters of your display based on its specifications via the OpenWF Display Configuration API (Wfdcfg Library).
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    The OpenWF Display Server (wfd-server) is a resource manager that provides applications the ability to show image buffers directly to the display controller via the OpenWF Display API.
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    QNX Screen Graphics Subsystem is a graphics framework that provides all the functionality necessary to develop interactive user experiences.
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    The video capture framework provides applications the ability to capture frames from a video input source. These frames can be passed to a graphics component such as Screen for display.
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Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

double_tap_params_t

QNX SDP8.0Gestures Library ReferenceAPIDeveloperProgramming

Double tap gesture parameters

Synopsis:

#include <gestures/>

typedef struct double_tap_params_t {
    unsigned max_displacement;
    unsigned max_hold_ms;
    unsigned max_delay_ms;
} double_tap_params_t;

Data:

unsigned max_displacement: The maximum distance the finger can move before the double tap gesture fails.
unsigned max_hold_ms: The maximum time the finger can remain touching the screen before the double tap gesture fails.
unsigned max_delay_ms: The time between the first release and the second touch.

Library:

libgestures

Description:

This stucture represents the parameters for the double tap gesture.

Page updated: March 05, 2025