隐藏状态栏后，如何让PopupWindow显示在屏幕最顶部？

问题原因 #

当Activity隐藏状态栏后，PopupWindow的默认布局逻辑仍会预留状态栏高度的空间，即便调用showAtLocation(view, Gravity.NO_GRAVITY, 0, 0)，也会出现顶部间隙。

解决方案 #

可以通过以下方式修复：

核心方案：设置PopupWindow忽略状态栏占位

在创建PopupWindow后，添加配置让它不受系统状态栏的影响，这是最直接的修复方式：

// 允许PopupWindow超出屏幕范围，避免被状态栏区域裁剪
popupWindow.setClippingEnabled(false);
// 给PopupWindow的内容视图设置全屏布局flag
WindowManager.LayoutParams params = (WindowManager.LayoutParams) contentView.getLayoutParams();
if (params == null) {
    params = new WindowManager.LayoutParams();
}
params.flags |= WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS;
contentView.setLayoutParams(params);

修改后的完整代码示例 #

Handler handler = new Handler(Looper.getMainLooper());
handler.postDelayed(() -> {
    View contentView = LayoutInflater.from(this).inflate(R.layout.popup_window_content, null, false);
    PopupWindow popupWindow = new PopupWindow(this);
    popupWindow.setContentView(contentView);
    popupWindow.setHeight(ViewUtil.dp2px(getResources().getDimension(R.dimen.dp_79)));
    popupWindow.setWidth(ViewUtil.dp2px(getResources().getDimension(R.dimen.screen_width)));
    
    // 添加修复配置
    popupWindow.setClippingEnabled(false);
    WindowManager.LayoutParams params = (WindowManager.LayoutParams) contentView.getLayoutParams();
    if (params == null) {
        params = new WindowManager.LayoutParams();
    }
    params.flags |= WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS;
    contentView.setLayoutParams(params);
    
    View view = mBinding.bg;
    Log.d("debug", "pos: "+view.getX()+" "+view.getY());
    popupWindow.showAtLocation(view, Gravity.NO_GRAVITY, 0, 0);

}, 1000);

内容的提问来源于stack exchange，提问作者ei zao