RecyclerView如何消除底部的分割線

最近遇到一個問題，用RecyclerView顯示數據，縱向列表顯示，添加默認分割線。

 

問題是：底部也會顯示分割線，這很影響美觀。

 

怎么解決這個問題呢？我想了很多辦法，毫無頭緒。。。

 

最后，查看默認分割線的類DividerItemDecoration的源碼：

public class DividerItemDecoration extends ItemDecoration {
    private static final int[] ATTRS = new int[]{16843284};
    public static final int HORIZONTAL_LIST = 0;
    public static final int VERTICAL_LIST = 1;
    private Drawable mDivider;
    private int mOrientation;

    public DividerItemDecoration(Context context, int orientation) {
        TypedArray a = context.obtainStyledAttributes(ATTRS);
        this.mDivider = a.getDrawable(0);
        a.recycle();
        this.setOrientation(orientation);
    }

    public void setOrientation(int orientation) {
        if(orientation != 0 && orientation != 1) {
            throw new IllegalArgumentException("invalid orientation");
        } else {
            this.mOrientation = orientation;
        }
    }

    public void onDraw(Canvas c, RecyclerView parent) {
        if(this.mOrientation == 1) {
            this.drawVertical(c, parent);
        } else {
            this.drawHorizontal(c, parent);
        }

    }

    public void drawVertical(Canvas c, RecyclerView parent) {
        int left = parent.getPaddingLeft();
        int right = parent.getWidth() - parent.getPaddingRight();
        int childCount = parent.getChildCount();

        for(int i = 0; i < childCount; ++i) {
            View child = parent.getChildAt(i);
            LayoutParams params = (LayoutParams)child.getLayoutParams();
            int top = child.getBottom() + params.bottomMargin;
            int bottom = top + this.mDivider.getIntrinsicHeight();
            this.mDivider.setBounds(left, top, right, bottom);
            this.mDivider.draw(c);
        }

    }

    public void drawHorizontal(Canvas c, RecyclerView parent) {
        int top = parent.getPaddingTop();
        int bottom = parent.getHeight() - parent.getPaddingBottom();
        int childCount = parent.getChildCount();

        for(int i = 0; i < childCount; ++i) {
            View child = parent.getChildAt(i);
            LayoutParams params = (LayoutParams)child.getLayoutParams();
            int left = child.getRight() + params.rightMargin;
            int right = left + this.mDivider.getIntrinsicHeight();
            this.mDivider.setBounds(left, top, right, bottom);
            this.mDivider.draw(c);
        }

    }

    public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) {
        if(this.mOrientation == 1) {
            outRect.set(0, 0, 0, this.mDivider.getIntrinsicHeight());
        } else {
            outRect.set(0, 0, this.mDivider.getIntrinsicWidth(), 0);
        }

    }
}

 

因為我用到的是垂直列表，用到的是紅色字體處的代碼：

 public void drawVertical(Canvas c, RecyclerView parent) {
        int left = parent.getPaddingLeft();
        int right = parent.getWidth() - parent.getPaddingRight();
        int childCount = parent.getChildCount();

        for(int i = 0; i < childCount; ++i) {
            View child = parent.getChildAt(i);
            LayoutParams params = (LayoutParams)child.getLayoutParams();
            int top = child.getBottom() + params.bottomMargin;
            int bottom = top + this.mDivider.getIntrinsicHeight();
            this.mDivider.setBounds(left, top, right, bottom);
            this.mDivider.draw(c);
        }

    }

從代碼中很容易看出只要修改for循環中的內容就可去掉底部的分割線：

 public void drawVertical(Canvas c, RecyclerView parent) {
        int left = parent.getPaddingLeft();
        int right = parent.getWidth() - parent.getPaddingRight();
        int childCount = parent.getChildCount();

        for(int i = 0; i < childCount-1; ++i) {
            View child = parent.getChildAt(i);
            LayoutParams params = (LayoutParams)child.getLayoutParams();
            int top = child.getBottom() + params.bottomMargin;
            int bottom = top + this.mDivider.getIntrinsicHeight();
            this.mDivider.setBounds(left, top, right, bottom);
            this.mDivider.draw(c);
        }

    }

因為這個類我們不能直接修改，所以我們可以自定義一個類，修改相應內容，

添加分割線的時候，使用自定義類。

 

大功告成！！！