Question

我正在尝试扩展ViewPager2类，以便允许左右拖动env->CallObjectMethod(instance, "score", "()Ljava/lang/String;");。

SeekBarPreference

但是我在class ViewPager2Custom(context: Context) : ViewPager2(context) { }的红线上得到了“此类型是最终类型，因此不能继承”。

有什么主意吗？

Answer 1

NestedScrollableHost类完全满足您的需求：https://github.com/android/views-widgets-samples/blob/master/ViewPager2/app/src/main/java/androidx/viewpager2/integration/testapp/NestedScrollableHost.kt

基本思想是，您重写onInterceptTouchEvent并请求NestedScrollableHost的父级（在本例中为ViewPager2）禁止其通过requestDisallowInterceptTouchEvent方法来拦截触摸事件。

// Pseudo-code for NestedScrollableHost

@Override
public boolean onInterceptTouchEvent(MotionEvent event) {
    handleInterceptTouchEvent(event);
    return super.onInterceptTouchEvent(event);
}

private void handleInterceptTouchEvent(MotionEvent event) {
    // Early return if parent viewpager is null or child can't scroll in same direction as parent
    if (getParentViewPager() == null ||
            (!canChildScrollVertically(-1f) && !canChildScrollVertically(1f))) {
        return;
    }

    switch (event.getAction()) {
        // You can tailor your class to handle the event in the way you want to,
        // e.g. do something on down and move events:
        case MotionEvent.ACTION_DOWN:
            // Disallow the parent (and all subsequent parents) to intercept touch events.
            getParent().requestDisallowInterceptTouchEvent(disallow);
        case MotionEvent.ACTION_MOVE:
            // Some other logic.
    }
}

您应将NestedScrollableHost放置在XML中的ViewPager2和SeekBarPreference之间。

“此类型是最终类型，因此无法继承”-ViewPager2

1 个答案: