android - 如何在android滑动标签布局中对齐 Activity 标签中心

Question

我在 android 滑动选项卡布局 + 查看寻呼机中有 12 个项目。从左向右滑动时，所选选项卡应与 Play 商店居中。请帮我怎么做。在我的应用程序中， Activity 选项卡始终位于屏幕左侧。

Answer 1

我的方法与 Shripad Bhat 有点不同解决方案，弹跳幻灯片末尾的选项卡。

这是我的解决方法...

onPageScrolled 方法的更改:

@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
    int tabStripChildCount = mTabStrip.getChildCount();
    if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) {
        return;
    }

    mTabStrip.onViewPagerPageChanged(position, positionOffset);

    View selectedTitle = mTabStrip.getChildAt(position);
    int selectedOffset = (selectedTitle == null) ? 0 : selectedTitle.getWidth();
    int nextTitlePosition = position + 1;
    View nextTitle = mTabStrip.getChildAt(nextTitlePosition);
    int nextOffset = (nextTitle == null) ? 0 : nextTitle.getWidth();
    int extraOffset = (int)(0.5F * (positionOffset * (float)(selectedOffset + nextOffset)));
    scrollToTab(position, extraOffset);

    if (mViewPagerPageChangeListener != null) {
        mViewPagerPageChangeListener.onPageScrolled(position, positionOffset, positionOffsetPixels);
    }
}

scrollToTab 方法的更改:

private int mLastScrollTo;

private void scrollToTab(int tabIndex, int positionOffset) {
    final int tabStripChildCount = mTabStrip.getChildCount();
    if (tabStripChildCount == 0 || tabIndex < 0 || tabIndex >= tabStripChildCount) {
        return;
    }

    View selectedChild = mTabStrip.getChildAt(tabIndex);
    if (selectedChild != null && selectedChild.getMeasuredWidth() != 0) {

        int targetScrollX = ((positionOffset + selectedChild.getLeft()) - getWidth() / 2) + selectedChild.getWidth() / 2;

        if (targetScrollX != mLastScrollTo) {
            scrollTo(targetScrollX, 0);
            mLastScrollTo = targetScrollX;
        }
    }
}