Sliding conflicts during mobile touch events can be resolved by the following methods: 1. Listen to touchstart and touchmove events to track user gestures. 2. Use event.preventDefault() to prevent the default behavior from controlling the passing of sliding events. 3. Calculate the sliding distance and speed and dynamically adjust the sliding behavior. 4. Use requestAnimationFrame to smoothly handle sliding events, ensuring animation effects and sliding controls.

Sliding conflicts during mobile touch events (touchstart, touchmove) are a common challenge when developing mobile applications. Let's start by understanding the problem and then dive into how to solve it.

On mobile, sliding conflicts usually occur between two or more slidable views, such as nested ScrollView or ListView. Suppose we have two ScrollViews, one is the parent container and the other is the child container. When the user slides on the child ScrollView, the slide of the parent ScrollView may be triggered, resulting in poor user experience.

To solve this problem, we need to carefully control and manage touch events. Here are some effective methods I personally summarized during the development process:

First, we can track user gestures by listening to touchstart and touchmove events. touchstart event can help us capture the start point of the user's touch, while touchmove event can allow us to track the user's finger movement.

 let startY = 0;
let currentY = 0;

document.addEventListener('touchstart', function(event) {
    startY = event.touches[0].clientY;
});

document.addEventListener('touchmove', function(event) {
    currentY = event.touches[0].clientY;
    const deltaY = currentY - startY;

    // Here you can judge the direction and distance of the sliding based on the value of deltaY if (deltaY > 0) {
        console.log('Swipe up');
    } else {
        console.log('Swipe down');
    }
});

With this simple example, we can see how touch events are used to track user gestures. However, this alone is not enough, we need to further deal with sliding conflicts.

A common method is to block default behavior through event.preventDefault() , thereby controlling the delivery of sliding events. For example, when we detect that the user is sliding on a child ScrollView, we can prevent the parent ScrollView from sliding:

 let isChildScrolling = false;

childScrollView.addEventListener('touchstart', function(event) {
    isChildScrolling = true;
    event.stopPropagation(); // Prevent events from bubbled into the parent ScrollView
});

childScrollView.addEventListener('touchmove', function(event) {
    if (isChildScrolling) {
        event.preventDefault(); // Prevent the parent ScrollView from sliding}
});

childScrollView.addEventListener('touchend', function(event) {
    isChildScrolling = false;
});

Although this method is simple, it should be noted that if event.preventDefault() is abused, other touch events may not work properly. Therefore, it needs to be used with caution in practical applications.

Another way is to determine whether the sliding event should be handled by the child ScrollView by calculating the sliding distance and speed. This method is more refined and can dynamically adjust the sliding behavior according to the user's gestures:

 let startY = 0;
let currentY = 0;
let startTime = 0;
let currentTime = 0;

childScrollView.addEventListener('touchstart', function(event) {
    startY = event.touches[0].clientY;
    startTime = new Date().getTime();
});

childScrollView.addEventListener('touchmove', function(event) {
    currentY = event.touches[0].clientY;
    currentTime = new Date().getTime();

    const deltaY = currentY - startY;
    const deltaTime = currentTime - startTime;

    const speed = Math.abs(deltaY / deltaTime);

    if (speed > 0.5) { // Assume 0.5 is an appropriate speed threshold event.preventDefault(); // Prevent the parent ScrollView from sliding}
});

The advantage of this method is that it can control the sliding behavior more accurately, but the speed threshold and sliding distance need to be adjusted according to the specific application scenario.

In actual development, I found a more flexible approach, which is to use requestAnimationFrame to smoothly handle sliding events. This method allows for better control of animation and sliding effects:

 let startY = 0;
let currentY = 0;
let isScrolling = false;

childScrollView.addEventListener('touchstart', function(event) {
    startY = event.touches[0].clientY;
    isScrolling = true;
});

childScrollView.addEventListener('touchmove', function(event) {
    currentY = event.touches[0].clientY;
    const deltaY = currentY - startY;

    if (isScrolling) {
        event.preventDefault();
        requestAnimationFrame(() => {
            // Here you can smoothly move sub-ScrollView according to deltaY
            childScrollView.scrollTop = deltaY;
        });
    }
});

childScrollView.addEventListener('touchend', function(event) {
    isScrolling = false;
});

Using requestAnimationFrame ensures that the sliding animation is smoother and provides better control over sliding conflicts.

In general, sliding conflicts during mobile touch events need to be considered comprehensively, including user gestures, sliding distance, speed, and nested relationships of views. Through the above methods, we can effectively solve the sliding conflict problem, but we need to choose the most appropriate method according to the specific application scenario.

In actual development, I also recommend that you test different phones and browsers more, because different devices and browsers may handle touch events differently. At the same time, we should also pay attention to the maintainability and readability of the code to ensure that no new problems are introduced while resolving sliding conflicts.

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