| Target selection and target dragging are common operation tasks in touch interaction interfaces.When completing target selection and target dragging tasks on a large touch screen,the target often exceeds the user’s reach.Direct Touch requires the user to frequently wave their arms or even be forced to move the body to reach the target position to complete the selection.Direct Drag needs to keep the finger in contact with the screen all the time.The long-distance sliding of the finger not only brings an uncomfortable feeling of friction,but also easily leads to the failure of the target to drag with the drop events,and it is easy to feel fatigued for users,which reduces the interactive experience.According to the different input methods and interactive tasks,two new target selection techniques and 2 target dragging techniques were proposed to improve the performance of interactive tasks on large touch screens.According to different touch input methods,target selection techniques for single-finger input and target dragging techniques for multi-finger input were proposed,including Double-click Ray,Double-click Mapping,Pick-and-Place and Sliding Transfer.The target selection techniques and target dragging techniques were compared with Direct Touch and Direct Drag respectively,and the performance of the new interactive techniques was discussed from quantitative and qualitative analysis.The results showed that for the target selection techniques,Double-click Mapping had the best comprehensive performance and was favored by users.The comprehensive performance of Thin-Ray and Thick-Ray of Double-click Ray and Mapping and Enlarge-Mapping of Double-click Mapping were better than Direct Touch,and the selection time was reduced by 0.43 s,0.58 s,2.11 s and 1.59 s respectively;the selection accuracy was increased 3.52%,2.69%,5.02% and 3.08%respectively.2 new target selection techniques improved the ability to access remote targets with one finger and outperform 2D-Dragger.For the target dragging techniques,the performance of Pick-and-Place and Sliding Transfer were improved.The selection time of the Pick-and-Place and the Sliding Transfer was reduced by 0.624 s and 0.623 s,respectively,and the selection accuracy was increased by 2.07% and 2.64%,respectively.The overall performance was better than that of Direct Drag.Pick-and-Place took the shortest time to complete the target dragging,and Sliding Transfer had the lowest error rate and the highest user evaluation.2 new target dragging techniques reduced the contact between the finger and the screen,avoiding the discomfort of long-distance dragging,and were better than Drag-and-Pop.Finally,according to the characteristics of new target selection and target dragging techniques,strategies for the use of novel interaction techniques for target selection tasks,target dragging tasks and hybrid tasks,respectively,were proposed.Considering practical applications,the application scenarios of target selection techniques and target dragging techniques based on different interaction scenarios,single and multi-person collaboration were designed,which provides a reference for the design of interactive techniques for large touch screens. |
