Touchscreen keyboard

Operating a touch-screen device includes displaying at least a portion of a keyboard on a touch-screen, detecting a touch on the touch-screen, and detecting movement of the touch on the touch-screen. Operating the touch-screen device also includes moving the displayed keyboard in response to the detected movement of the touch on the touch-screen, detecting a release of the touch from the touch-screen, and assigning a character according to a final location of the touch relative to a location of the displayed keyboard.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Great Britain Patent Application No. 1312184.3, filed 8 Jul. 2013, and all the benefits accruing therefrom under 35 U.S.C. § 119, the contents of which in its entirety are herein incorporated by reference.

BACKGROUND

The present disclosure relates generally to touch-screen technology and, more particularly, to a touch-screen device and method of operation.

In the mobile telephony world, touch sensitive devices enable soft keyboard usage, which keyboard is used for entering textual information, such as when a user is filling in a web form or sending a message. Soft keyboards refer to a software implementation of an otherwise hardware-based keyboard. Soft keyboards can be shown on demand and can be adapted to different locales and participants' preferences. In addition, an on-screen keyboard helps to support hardware size reduction.

Soft keyboards are designed to fit entirely into the screen real estate, and oftentimes a mobile telephone is used in portrait mode. In such a context, where a small portion of the screen is reserved for the keyboard area, a user may experience difficulties in accurately typing a key that is not readily seen, as the user's finger often occupies the space of two or more keyboard letters. This can result in the user depressing the wrong key.

SUMMARY

According to a first aspect of the present invention, there is provided a method of operating a touch-screen device. The method includes displaying at least a portion of a keyboard on a touch-screen of the touch-screen device, detecting a touch on the touch-screen, and detecting movement of the touch on the touch-screen. The method also includes moving the displayed keyboard in response to the detected movement of the touch on the touch-screen, detecting a release of the touch from the touch-screen, and assigning a character according to a final location of the touch relative to a location of the displayed keyboard.

According to a second aspect of the present invention, there is provided a touch-screen device. The touch-screen device includes a touch-screen and a processor connected to the touch-screen. The processor is configured to display at least a portion of a keyboard on the touch-screen, detect a touch on the touch-screen, and detect movement of the touch on the touch-screen. The processor is also configured to move the displayed keyboard in response to the detected movement of the touch on the touch-screen, detect a release of the touch from the touch-screen, and assign a character according to a final location of the touch relative to a location of the displayed keyboard.

According to a third aspect of the present invention, there is provided a computer program product for operating a touch-screen device. The computer program product includes a computer readable storage medium having program instructions embodied therewith, the program instructions readable by a processing circuit to cause the processing circuit to display at least a portion of a keyboard on a touch-screen of the touch-screen device, detect a touch on the touch-screen, and detect movement of the touch on the touch-screen. The product further includes instructions for moving the displayed keyboard in response to the detected movement of the touch on the touch-screen, detecting a release of the touch from the touch-screen, and assigning a character according to a final location of the touch relative to a location of the displayed keyboard.

DETAILED DESCRIPTION

Embodiments of the present disclosure provide an improved on-screen keyboard having relatively large keys and is straightforward to operate. The embodiments provide a means for helping users efficiently use soft keyboards and to minimize the number of incorrect inputs. The improved touch-screen device minimizes the number of input errors when touching soft keyboards for users whose fingers are too large for consistently accurately selecting a key. Since a user's fingers cannot be made smaller, the soft keyboard is enlarged thereby increasing the key size so that users can type without error.

Increasing the touch key size also implies increasing the size of the full keyboard itself, such that the keyboard may no longer fit within the screen real estate, thereby resulting in out-of-screen keys not being directly accessible to the user. The embodiments described herein provide a keyboard that is ‘floatable’ within the screen bounds and moves in such a way that as user's finger moves, the target key is displaced toward the moving finger. In other words, the user's finger and keyboard move in opposite directions so that the finger and target key become closer.

According to some embodiments, a set of two events are used for the target key to be recognized, as compared to a fixed keyboard (which is entirely accessible), in that a single touch down event is sufficient for a key to be selected. In the embodiments described herein, the touch-screen device offers the user two capabilities: the capability to make any key, including off screen keys, reachable by sliding the keyboard in the opposite finger direction; and the capability to select any available key, including accentuated popup characters. Both of these capabilities are handled using different touch events. The first event is implemented by touch drag event recognition, and the second event is implemented using touch up recognition. The touch down event is used only to initialize the starting point of the first drag vector direction. In the case where the key is directly accessible to the user (no drag is involved) the user simply needs to act the same way as for a normal keyboard, the selected key being also recognized with the touch up event.

The touch-screen also offers the user the capability to adjust the full keyboard size by zooming the keyboard. This capability is handled using the recognition of a “pinch” gesture that consists in detecting two finger gestures and calculating a zoom factor using the variation of distance between both the fingers on each drag event. Once the zoom factor is obtained, the touch-screen device checks that the keyboard width is at least as large as the screen width and that the screen height is at least as big as the keyboard height before zooming the keyboard. This ensures that the keyboard remains usable.

When a user needs to select an accentuated character by using a popup sub keyboard containing all of the accentuated derivatives from the selected character, the touch-screen device can track the change of position of the user's finger on a key over time and deduce that while this position does not change and the touch up event does not occur, the touch-screen device can popup an accentuated characters sub keyboard, if available, for the considered key. This allows the user to access accented characters, for example, while still offering the functionality of allowing a larger keyboard to be used.

In an embodiment, the step of moving the displayed keyboard in response to the detected movement of the touch on the touch-screen includes moving the displayed keyboard in the opposite direction to the detected movement of the touch on the touch-screen and moving the displayed keyboard an equal distance to the detected movement of the touch on the touch-screen. As the user touches the touch-screen device with his finger and starts to move his finger across the touch-screen (in any direction), the keyboard displayed on the touch-screen starts to move in an equal and opposite manner to the movement of the user's finger. This effectively scrolls the keyboard across the touch-screen, allowing the user to access those keys of the keyboard that are not currently displayed on the touch-screen. The use of an equal and opposite rate of movement gives the most user friendly and logical movement of the keyboard in response to the user's moving touch and provides the user with an intuitive interaction with the soft keyboard of the touch-screen.

Turning now toFIG. 1, a touch-screen10is provided. The touch-screen device10, here a mobile phone, has a touch-screen12occupying the vast majority of the front of the touch-screen device10. The user interacts with the touch-screen device10primarily by touching the touch-screen12with his finger or with a suitable stylus, depending upon the type of touch-screen12being used in the touch-screen device10. The touch-screen device10is controlled by an internal processor, under the operation of a suitable computer program, which is connected to the touch-screen12and receives the user's inputs on the touch-screen12and controls the output on the touch-screen12accordingly. The user controls the touch-screen device10by interacting with the touch-screen12.

The touch-screen device10is controlled by the processor to display a soft keyboard14on the touch-screen12. The keyboard14is “soft” in the sense that it is not a hardware keyboard such as used with a conventional desktop PC but is a software implementation of the keyboard. Only a portion of the keyboard14is currently visible on the touch-screen12. This allows the individual keys16of the keyboard14to be larger than would otherwise be the case if the entire keyboard14was shown on the touch-screen12. However, by enlarging the keys16, certain keys16are not directly accessible to the user.

The soft keyboard14shown on the touch-screen12of the touch-screen device10is a standard QWERTY keyboard that is very widely used in the Western world. The vast majority of typewriters and computer keyboards in the Western world use this layout of keys, which arranges the keys according to their frequency in the English language, mapping the common keys to the easiest position to find with the fingers of the user's hands. The common user will know that the layout of the keys of the keyboard14imply that the remainder of the keys are (virtually) off the touch-screen12to the right-hand side and cannot be directly accessed.

FIG. 2illustrates how a user accesses a key that is not currently visible on the touch-screen12. In this example, the user wishes to access the key “P”, which is not part of the portion of the keyboard14currently being displayed on the touch-screen12. The letter “P” on a standard QWERTY keyboard is found on the top line of letters at the furthest point to the right-hand side. It is not necessary that the user know the exact location of the key in question, only that he be aware that it is not currently visible. The user touches down on a first letter (here the letter “Q”) and starts dragging his finger to the right.

When the user drags his finger towards the target letter, the keyboard14is moved in the opposite direction to the movement of the finger, thereby showing parts of the keyboard14that were previously hidden. In an embodiment, the movement of the keyboard14is equal and opposite to the movement of the user's touch on the touch-screen12. This provides a simple and intuitive movement of the keyboard14, in response to the detected movement of the user's touch on the touch-screen12. The user is now able to reach those characters that were not previously directly accessible, as they were not part of the portion of the keyboard visible from the starting position.

FIG. 3shows the user continuing to drag his finger towards the target letter “P”. The view shown in this Figure is an intermediate position, the letter “T” is currently highlighted, in order to show the current key16that the user is selecting. The keyboard14has moved to the left in this Figure relative to the position of the keyboard14inFIGS. 1 and 2. As the user continues to drag his touch to the right, then the keyboard14will continue to move to the left in an equal and opposite motion. The processor of the touch-screen device10controls the scrolling of the keyboard14in response to the detection of the user's movement of his finger across the touch-screen12.

Once the user has moved his finger across the touch-screen12to reach the target letter, he can then release his finger in order to select the desired character.FIG. 4shows the user releasing his finger from the target letter “P”, which results in the processor of the touch-screen device10assigning the character “P” according to the final location of the user's touch relative to the location of the displayed keyboard14. As can be seen in this Figure, the letter “P” has now been displayed at the text cursor and the user can continue selecting keys16of the keyboard14to continue typing. If the user needs to select a key16that is not currently visible, then as before, he can drag his finger on the touch-screen12to cause the keyboard14to move in the opposite direction to the drag movement.

FIG. 5shows a flowchart summarizing the method of operating the touch-screen device10. The method includes, at block S5.1, displaying at least a portion of the keyboard14on the touch-screen12. When the user is operating the touch-screen device10in any mode that requires a text input, then the keyboard14is shown in a lower portion of the touch-screen12, as illustrated inFIG. 1. This portion of the keyboard14that is shown is either a predefined start portion or is the last displayed portion, from the user's last interaction with the keyboard14.

At block S5.2, a touch is detected on the touch-screen12. This touch could be with the user's finger or with a stylus; this is not material to the operation of the method. At block S5.3, movement of the touch on the touch-screen12is detected, which indicates that the user is performing a dragging motion of his finger (or stylus). At block S5.4, the displayed keyboard14is moved in response to the detected movement of the touch on the touch-screen12. As discussed above, in an embodiment, this movement is equal and opposite to the detected movement of the touch on the touch-screen12.

At block S5.5, the release of the touch from the touch-screen12is detected, and at block S5.6, a character is assigned according to the final location of the touch relative to the location of the displayed keyboard14. Once the processor of the touch-screen device10detects that the user's touch has been released, then a character is assigned to the touch, according to the position of the last touch relative to the keyboard's position as currently displayed on the touch-screen12. In this way, an improved input method is delivered, which can use relatively larger keys on the keyboard and can still provide the user with easy access to all of the keys of the keyboard.

The processor of the touch-screen device10may operate the following pseudo-code in controlling the operation of the touch-screen12:

1. layout the keyboard

2. adjust the keyboard size so that its height fits the screen height and that the screen width is only a part of the keyboard width (a maximum of two vertically aligned keyboard corners must be visible at the same time)

3. wait for an event (global event loop)

3.1. if a finger touch down appears3.1.1. identify the letter under the finger (if any)3.1.2. if the next event is a one finger drag event3.1.2.1. calculate the finger position difference between this event and the previous one: in other words, calculate the finger displacement3.1.2.2. if the displacement is not zero3.1.2.2.1. check whether any keyboard corner cannot move inside the view as a result of this displacement and eventually modify the displacement values accordingly3.1.2.2.2. move the keyboard in the opposite direction to the finger using the calculation result3.1.2.2.3. identify the current overfly key3.1.2.3. else if the finger is stationary for a sufficient amount of time3.1.2.3.1. process eventual accentuated character if available.3.1.3. else if it is a one finger touch up event3.1.3.1. identify the selected key and send it to the interested component3.1.4. else return in the global event loop step

3.2. else if a screen orientation changes, return to the adjust to screen step (step 2)

In this way, the touch-screen device10provides the improved methodology. Non-standard characters can be delivered by the process, as once the user has scrolled the keyboard14to reach a desired key, if he maintains his touch on the specific character for a short period of time, a sub-keyboard is displayed by the touch-screen12and the user can make a second touch on the sub-keyboard to indicate which character he wishes to select. All other normal functions on the keyboard14may work as usual, such as backspace and return, and the user can access these functions by scrolling the keyboard with finger dragging to reach these function keys in the same manner as described above.