如何获得透明软键栏和透明状态栏的高度？答案

【问题标题】：How to get heights of a transparent softkeys bar and transparent status bar?如何获得透明软键栏和透明状态栏的高度？
【发布时间】：2017-03-08 19:18:44
【问题描述】：

我有一个包含 RecyclerView 和透明状态栏（包含 wifi 信号等...）和软键栏的活动。当然，RecyclerView 中的项目数量是未定义的，我需要第一个具有标准上边距加上状态栏高度，最后一个具有标准下边距加上软键栏的高度。这是必需的，否则当滚动条分别位于顶部或底部时，我将得到第一个和最后一个项目部分被条覆盖。

这是我如何以编程方式处理边距的示例代码：

DisplayMetrics metrics = new DisplayMetrics();
        activity.getWindowManager().getDefaultDisplay().getMetrics(metrics);

        topSpace = new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
        bottomSpace = new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
        standardSpace = new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);

        topSpace.setMargins(     (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics),
                                 (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8 + 24, metrics),
                                 (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics),
                                 (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics));

        bottomSpace.setMargins(  (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics),
                                 (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics),
                                 (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics),
                                 (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8 + 56, metrics) +
                                         getSoftkeysHeight(activity));

        standardSpace.setMargins((int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics),
                                 (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics),
                                 (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics),
                                 (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8,    metrics));

我正在尝试使用those answers，但它们似乎对我没有帮助，因为屏幕的可绘制表面确实是整个屏幕...

【问题讨论】：

标签： android android-recyclerview android-statusbar

【解决方案1】：

您可以使用RecyclerView.ItemDecoration 修改特定项目的边距。

创建一个扩展 RecyclerView.ItemDecoration 的类：

public static class SimpleItemDecorator extends RecyclerView.ItemDecoration {

private int regularMargin;
private int lastPosition;
private int statusBarHeight;
private int navigationBarHeight;

public SimpleItemDecorator(Activity activity, int recyclerViewItemsCount) {
    // get the regular margin
    regularMargin = activity.getResources().getDimensionPixelSize(R.dimen.regularMargin);

    // determine the last position
    lastPosition = recyclerViewItemsCount - 1;

    // get the height of the status bar
    final Rect rectangle = new Rect();
    final Window window = activity.getWindow();
    window.getDecorView().getWindowVisibleDisplayFrame(rectangle);
    statusBarHeight = rectangle.top;

    // get the height of the navigation bar
    final int redId = resources.getIdentifier("navigation_bar_height", "dimen", "android");
    navigationBarHeight = (redId > 0) ? resources.getDimensionPixelSize(resId) : 0;

}

@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
    // modify the margins
    final int position = parent.getChildAdapterPosition(view);
    if (position == 0) {
        outRect.top = statusBarHeight + regularMargin;
    } else if (position == lastPosition) {
        outRect.bottom = navigationBar + regularMargin;
    }
}

}

将创建的ItemDecorator 添加到 RecyclerView ：

final int recyclerViewItemsCount = 6;
final SimpleItemDecorator itemDecorator = new SimpleItemDecorator(this, recyclerViewItemsCount);
recyclerView.addItemDecorator(itemDecorator);

【讨论】：