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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.
two_finger_double_tap.h
Definition of the double tap gesture.
gesture_two_finger_double_tap_t
The two-finger double tap gesture data type

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This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
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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.
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      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.
      - 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.
        gesture_two_finger_double_tap_t
        The two-finger double tap gesture data type
        two_finger_double_tap_gesture_alloc()
        Allocate and initialize the two-finger double tap gesture structure
        two_finger_double_tap_gesture_default_params()
        Initialize the two-finger double tap parameters
        two_finger_double_tap_params_t
        Two-finger double tap gesture parameters
        two_finger_double_tap_state_e
        States for the two-finger double tap gesture
      - types.h
        Common data types and helper functions.
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    The Input Events library provides the framework necessary for Screen Graphics Subsystem to communicate with your touch driver.
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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.

gesture_two_finger_double_tap_t

QNX SDP8.0Gestures Library ReferenceAPIDeveloperProgramming

The two-finger double tap gesture data type

Synopsis:

#include <gestures/two_finger_double_tap.h>

typedef struct gesture_two_finger_double_tap_t {
    gesture_base_t base;
    two_finger_double_tap_params_t params;
    gesture_coords_t first_touch[2];
    gesture_coords_t first_release[2];
    gesture_coords_t second_touch[2];
    gesture_coords_t second_release[2];
    gesture_coords_t centroid;
    gesture_coords_t last_centroid;
    two_finger_double_tap_state_e dt_state;
    int fail_timer;
    unsigned down_count;
} gesture_two_finger_double_tap_t;

Data:

gesture_base_t base: The gesture base data structure.
two_finger_double_tap_params_t params: The two-finger double tap parameters.
gesture_coords_t first_touch[2]: The coordinates of the first touch.
gesture_coords_t first_release[2]: The coordinates of the first release.
gesture_coords_t second_touch[2]: The coordinates of the second touch.
gesture_coords_t second_release[2]: The coordinates of the second release.
gesture_coords_t centroid: The coordintes of the midpoint between the two touches.
gesture_coords_t last_centroid: The coordintes of the midpoint between the previous two touches.
two_finger_double_tap_state_e dt_state: The intermediate state of the two-finger double tap.
int fail_timer: The ID of the timer for this gesture.
unsigned down_count: The number of fingers that are simultaneously in contact with the touch device.

Library:

libgestures

Description:

This structure carries data about the two-finger double tap gesture.

Page updated: March 05, 2025