注意 最新的TabLayout 下劃線 mTabStrip 改為slidingTabIndicator

public static void setIndicator(TabLayout tabs, int leftDip, int rightDip) { Class<?> tabLayout = tabs.getClass(); Field tabStrip = null; try { tabStrip = tabLayout.getDeclaredField(“slidingTabIndicator”); } catch (NoSuchFieldException e) { e.printStackTrace(); }

    tabStrip.setAccessible(true);
    LinearLayout llTab = null;
    try {
        llTab = (LinearLayout) tabStrip.get(tabs);
    } catch (IllegalAccessException e) {
        e.printStackTrace();
    }

    int left = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, leftDip, Resources.getSystem().getDisplayMetrics());
    int right = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, rightDip, Resources.getSystem().getDisplayMetrics());

    for (int i = 0; i < llTab.getChildCount(); i++) {
        View child = llTab.getChildAt(i);
        child.setPadding(0, 0, 0, 0);
        LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.MATCH_PARENT, 1);
        params.leftMargin = left;
        params.rightMargin = right;
        child.setLayoutParams(params);
        child.invalidate();
    }
}
 

tabLayout.post(new Runnable() { @Override public void run() { setIndicator(tabLayout, 50, 50); } });