Android RecycleView 网格分割线

已经不记得是从哪里转载的了 RecycleView很好用但是不熟悉 这个分割线写下记录一下

新建一个名称为 RecyclerViewItemDecoration 的类即可

import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.DashPathEffect;import android.graphics.NinePatch;import android.graphics.Paint;import android.graphics.Path;import android.graphics.PathEffect;import android.graphics.Rect;import android.support.annotation.ColorInt;import android.support.v7.widget.GridLayoutManager;import android.support.v7.widget.RecyclerView;import android.view.View;import java.util.regex.Pattern;/** * RecycleView item decoration * Created by Eminem Lu on 24/11/15. * Email [e-mail] */public class RecyclerViewItemDecoration extends RecyclerView.ItemDecoration {    /**     * mode for direction     */    public static final int MODE_HORIZONTAL = 0;    public static final int MODE_VERTICAL = 1;    public static final int MODE_GRID = 2;    /**     * default decoration color     */    private static final String DEFAULT_COLOR = "#cccccc";    /**     * image resource id for R.java     */    private int mDrawableRid = 0;    /**     * decoration color     */    private int mColor = Color.parseColor(DEFAULT_COLOR);    /**     * decoration thickness     */    private int mThickness;    /**     * decoration dash with     */    private int mDashWidth = 0;    /**     * decoration dash gap     */    private int mDashGap = 0;    private boolean mFirstLineVisible;    private boolean mLastLineVisible;    private int mPaddingStart = 0;    private int mPaddingEnd = 0;    /**     * direction mode for decoration     */    private int mMode;    private Paint mPaint;    private Bitmap mBmp;    private NinePatch mNinePatch;    /**     * choose the real thickness for image or thickness     */    private int mCurrentThickness;    /**     * sign for if the resource image is a ninepatch image     */    private Boolean hasNinePatch = false;    public RecyclerViewItemDecoration() {    }    @Deprecated    public RecyclerViewItemDecoration(int recyclerviewMode, Context context, int drawableRid) {        this.mMode = recyclerviewMode;        this.mDrawableRid = drawableRid;        this.mBmp = BitmapFactory.decodeResource(context.getResources(), drawableRid);        if (mBmp.getNinePatchChunk() != null) {            hasNinePatch = true;            mNinePatch = new NinePatch(mBmp, mBmp.getNinePatchChunk(), null);        }        initPaint();    }    @Deprecated    public RecyclerViewItemDecoration(int recyclerviewMode, int color, int thick, int dashWidth, int dashGap) {        this.mMode = recyclerviewMode;        this.mColor = color;        this.mThickness = thick;        this.mDashWidth = dashWidth;        this.mDashGap = dashGap;        initPaint();    }    @Deprecated    public RecyclerViewItemDecoration(int recyclerviewMode, String color, int thick, int dashWidth, int dashGap) {        this.mMode = recyclerviewMode;        if (isColorString(color)) {            this.mColor = Color.parseColor(color);        } else {            this.mColor = Color.parseColor(DEFAULT_COLOR);        }        this.mThickness = thick;        this.mDashWidth = dashWidth;        this.mDashGap = dashGap;        initPaint();    }    public void setParams(Context context, Param params) {        this.mMode = params.mode;        this.mDrawableRid = params.drawableRid;        this.mColor = params.color;        this.mThickness = params.thickness;        this.mDashGap = params.dashGap;        this.mDashWidth = params.dashWidth;        this.mPaddingStart = params.paddingStart;        this.mPaddingEnd = params.paddingEnd;        this.mFirstLineVisible = params.firstLineVisible;        this.mLastLineVisible = params.lastLineVisible;        this.mBmp = BitmapFactory.decodeResource(context.getResources(), mDrawableRid);        if (mBmp != null) {            if (mBmp.getNinePatchChunk() != null) {                hasNinePatch = true;                mNinePatch = new NinePatch(mBmp, mBmp.getNinePatchChunk(), null);            }            if (mMode == MODE_HORIZONTAL)                mCurrentThickness = mThickness == 0 ? mBmp.getHeight() : mThickness;            if (mMode == MODE_VERTICAL)                mCurrentThickness = mThickness == 0 ? mBmp.getWidth() : mThickness;        }        initPaint();    }    private void initPaint() {        mPaint = new Paint();        mPaint.setColor(mColor);        mPaint.setStyle(Paint.Style.STROKE);        mPaint.setStrokeWidth(mThickness);    }    @Override    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {        mPaint.setColor(mColor);        if (mMode == MODE_HORIZONTAL) {            drawHorinzonal(c, parent);        } else if (mMode == MODE_VERTICAL) {            drawVertical(c, parent);        } else if (mMode == MODE_GRID) {            drawGrid(c, parent);        }    }    @Override    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {        if (mMode == MODE_HORIZONTAL) {            if (!(!mLastLineVisible &&                    parent.getChildLayoutPosition(view) == parent.getAdapter().getItemCount() - 1)) {                if (mDrawableRid != 0) {                    outRect.set(0, 0, 0, mCurrentThickness);                } else {                    outRect.set(0, 0, 0, mThickness);                }            }            if (mFirstLineVisible && parent.getChildLayoutPosition(view) == 0) {                if (mDrawableRid != 0) {                    outRect.set(0, mCurrentThickness, 0, mCurrentThickness);                } else {                    outRect.set(0, mThickness, 0, mThickness);                }            }        } else if (mMode == MODE_VERTICAL) {            if (!(!mLastLineVisible &&                    parent.getChildLayoutPosition(view) == parent.getAdapter().getItemCount() - 1)) {                if (mDrawableRid != 0) {                    outRect.set(0, 0, mCurrentThickness, 0);                } else {                    outRect.set(0, 0, mThickness, 0);                }            }            if (mFirstLineVisible && parent.getChildLayoutPosition(view) == 0) {                if (mDrawableRid != 0) {                    outRect.set(mCurrentThickness, 0, mCurrentThickness, 0);                } else {                    outRect.set(mThickness, 0, mThickness, 0);                }            }        } else if (mMode == MODE_GRID) {            int columnSize = ((GridLayoutManager) parent.getLayoutManager()).getSpanCount();            int itemSzie = parent.getAdapter().getItemCount();            if (mDrawableRid != 0) {                if (isLastRowGrid(parent.getChildLayoutPosition(view), itemSzie, columnSize)                        && isLastGridColumn(parent.getChildLayoutPosition(view), columnSize)) {                    outRect.set(0, 0, 0, 0);                } else if (isLastRowGrid(parent.getChildLayoutPosition(view), itemSzie, columnSize)) {                    outRect.set(0, 0, mBmp.getWidth(), 0);                } else if ((parent.getChildLayoutPosition(view) + 1) % columnSize != 0) {                    outRect.set(0, 0, mBmp.getWidth(), mBmp.getHeight());                } else {                    outRect.set(0, 0, 0, mBmp.getHeight());                }            } else {                if (isLastRowGrid(parent.getChildLayoutPosition(view), itemSzie, columnSize)                        && isLastGridColumn(parent.getChildLayoutPosition(view), columnSize)) {                    outRect.set(0, 0, 0, 0);                } else if (isLastRowGrid(parent.getChildLayoutPosition(view), itemSzie, columnSize)) {                    outRect.set(0, 0, mThickness, 0);                } else if ((parent.getChildLayoutPosition(view) + 1) % columnSize != 0) {                    outRect.set(0, 0, mThickness, mThickness);                } else {                    outRect.set(0, 0, 0, mThickness);                }            }        }    }    /**     * judge is a color string like #xxxxxx or #xxxxxxxx     *     * @param colorStr     * @return     */    public static boolean isColorString(String colorStr) {        return Pattern.matches("^#([0-9a-fA-F]{6}||[0-9a-fA-F]{8})$", colorStr);    }    private boolean isPureLine() {        if (mDashGap == 0 && mDashWidth == 0)            return true;        return false;    }    /**     * draw horizonal decoration     *     * @param c     * @param parent     */    private void drawHorinzonal(Canvas c, RecyclerView parent) {        int childrentCount = parent.getChildCount();        if (mDrawableRid != 0) {            if (mFirstLineVisible) {                View childView = parent.getChildAt(0);                int myY = childView.getTop();                if (hasNinePatch) {                    Rect rect = new Rect(mPaddingStart, myY - mCurrentThickness, parent.getWidth() - mPaddingEnd, myY);                    mNinePatch.draw(c, rect);                } else {                    c.drawBitmap(mBmp, mPaddingStart, myY - mCurrentThickness, mPaint);                }            }            for (int i = 0; i < childrentCount; i++) {                if (!mLastLineVisible && i == childrentCount - 1)                    break;                View childView = parent.getChildAt(i);                int myY = childView.getBottom();                if (hasNinePatch) {                    Rect rect = new Rect(mPaddingStart, myY, parent.getWidth() - mPaddingEnd, myY + mCurrentThickness);                    mNinePatch.draw(c, rect);                } else {                    c.drawBitmap(mBmp, mPaddingStart, myY, mPaint);                }            }        } else {            boolean isPureLine = isPureLine();            if (!isPureLine) {                PathEffect effects = new DashPathEffect(new float[]{0, 0, mDashWidth, mThickness}, mDashGap);                mPaint.setPathEffect(effects);            }            if (mFirstLineVisible) {                View childView = parent.getChildAt(0);                int myY = childView.getTop() - mThickness/ 2 ;                if (isPureLine) {                    c.drawLine(mPaddingStart, myY, parent.getWidth() - mPaddingEnd, myY, mPaint);                } else {                    Path path = new Path();                    path.moveTo(mPaddingStart, myY);                    path.lineTo(parent.getWidth() - mPaddingEnd, myY);                    c.drawPath(path, mPaint);                }            }            for (int i = 0; i < childrentCount; i++) {                if (!mLastLineVisible && i == childrentCount - 1)                    break;                View childView = parent.getChildAt(i);                int myY = childView.getBottom() + mThickness / 2;                if (isPureLine) {                    c.drawLine(mPaddingStart, myY, parent.getWidth() - mPaddingEnd, myY, mPaint);                } else {                    Path path = new Path();                    path.moveTo(mPaddingStart, myY);                    path.lineTo(parent.getWidth() - mPaddingEnd, myY);                    c.drawPath(path, mPaint);                }            }        }    }    /**     * draw vertival decoration     *     * @param c     * @param parent     */    private void drawVertical(Canvas c, RecyclerView parent) {        int childrentCount = parent.getChildCount();        if (mDrawableRid != 0) {            if (mFirstLineVisible) {                View childView = parent.getChildAt(0);                int myX = childView.getLeft();                if (hasNinePatch) {                    Rect rect = new Rect(myX - mCurrentThickness, mPaddingStart, myX, parent.getHeight() - mPaddingEnd);                    mNinePatch.draw(c, rect);                } else {                    c.drawBitmap(mBmp, myX - mCurrentThickness, mPaddingStart, mPaint);                }            }            for (int i = 0; i < childrentCount; i++) {                if (!mLastLineVisible && i == childrentCount - 1)                    break;                View childView = parent.getChildAt(i);                int myX = childView.getRight();                if (hasNinePatch) {                    Rect rect = new Rect(myX, mPaddingStart, myX + mCurrentThickness, parent.getHeight() - mPaddingEnd);                    mNinePatch.draw(c, rect);                } else {                    c.drawBitmap(mBmp, myX, mPaddingStart, mPaint);                }            }        } else {            boolean isPureLine = isPureLine();            if (!isPureLine) {                PathEffect effects = new DashPathEffect(new float[]{0, 0, mDashWidth, mThickness}, mDashGap);                mPaint.setPathEffect(effects);            }            if (mFirstLineVisible) {                View childView = parent.getChildAt(0);                int myX = childView.getLeft() - mThickness / 2;                if (isPureLine) {                    c.drawLine(myX, mPaddingStart, myX, parent.getHeight() - mPaddingEnd, mPaint);                } else {                    Path path = new Path();                    path.moveTo(myX, mPaddingStart);                    path.lineTo(myX, parent.getHeight() - mPaddingEnd);                    c.drawPath(path, mPaint);                }            }            for (int i = 0; i < childrentCount; i++) {                if (!mLastLineVisible && i == childrentCount - 1)                    break;                View childView = parent.getChildAt(i);                int myX = childView.getRight() + mThickness / 2;                if (isPureLine) {                    c.drawLine(myX, mPaddingStart, myX, parent.getHeight() - mPaddingEnd, mPaint);                } else {                    Path path = new Path();                    path.moveTo(myX, mPaddingStart);                    path.lineTo(myX, parent.getHeight() - mPaddingEnd);                    c.drawPath(path, mPaint);                }            }        }    }    /**     * draw grid decoration     *     * @param c     * @param parent     */    private void drawGrid(Canvas c, RecyclerView parent) {        int childrentCount = parent.getChildCount();        int columnSize = ((GridLayoutManager) parent.getLayoutManager()).getSpanCount();        int adapterChildrenCount = parent.getAdapter().getItemCount();        if (mDrawableRid != 0) {            if (hasNinePatch) {                for (int i = 0; i < childrentCount; i++) {                    View childView = parent.getChildAt(i);                    int myX = childView.getRight();                    int myY = childView.getBottom();                    //horizonal                    if (!isLastRowGrid(i, adapterChildrenCount, columnSize)) {                        Rect rect = new Rect(0, myY, myX, myY + mBmp.getHeight());                        mNinePatch.draw(c, rect);                    }                    //vertical                    if (isLastRowGrid(i, adapterChildrenCount, columnSize)                            && !isLastGridColumn(i, columnSize)) {                        Rect rect = new Rect(myX, childView.getTop(), myX + mBmp.getWidth(), myY);                        mNinePatch.draw(c, rect);                    } else if (!isLastGridColumn(i, columnSize)) {                        Rect rect = new Rect(myX, childView.getTop(), myX + mBmp.getWidth(), myY + mBmp.getHeight());                        mNinePatch.draw(c, rect);                    }                }            } else {                for (int i = 0; i < childrentCount; i++) {                    View childView = parent.getChildAt(i);                    int myX = childView.getRight();                    int myY = childView.getBottom();                    //horizonal                    if (!isLastRowGrid(i, adapterChildrenCount, columnSize)) {                        c.drawBitmap(mBmp, childView.getLeft(), myY, mPaint);                    }                    //vertical                    if (!isLastGridColumn(i, columnSize)) {                        c.drawBitmap(mBmp, myX, childView.getTop(), mPaint);                    }                }            }        } else if (mDashWidth == 0 && mDashGap == 0) {            for (int i = 0; i < childrentCount; i++) {                View childView = parent.getChildAt(i);                int myX = childView.getRight() + mThickness / 2;                int myY = childView.getBottom() + mThickness / 2;                //horizonal                if (!isLastRowGrid(i, adapterChildrenCount, columnSize)) {                    c.drawLine(childView.getLeft(), myY, childView.getRight() + mThickness, myY, mPaint);                }                //vertical                if (isLastRowGrid(i, adapterChildrenCount, columnSize)                        && !isLastGridColumn(i, columnSize)) {                    c.drawLine(myX, childView.getTop(), myX, childView.getBottom(), mPaint);                } else if (!isLastGridColumn(i, columnSize)) {                    c.drawLine(myX, childView.getTop(), myX, myY, mPaint);                }            }        } else {            PathEffect effects = new DashPathEffect(new float[]{0, 0, mDashWidth, mThickness}, mDashGap);            mPaint.setPathEffect(effects);            for (int i = 0; i < childrentCount; i++) {                View childView = parent.getChildAt(i);                int myX = childView.getRight() + mThickness / 2;                int myY = childView.getBottom() + mThickness / 2;                //horizonal                if (!isLastRowGrid(i, adapterChildrenCount, columnSize)) {                    Path path = new Path();                    path.moveTo(0, myY);                    path.lineTo(myX, myY);                    c.drawPath(path, mPaint);                }                //vertical                if (isLastRowGrid(i, adapterChildrenCount, columnSize)                        && !isLastGridColumn(i, columnSize)) {                    Path path = new Path();                    path.moveTo(myX, childView.getTop());                    path.lineTo(myX, childView.getBottom());                    c.drawPath(path, mPaint);                } else if (!isLastGridColumn(i, columnSize)) {                    Path path = new Path();                    path.moveTo(myX, childView.getTop());                    path.lineTo(myX, childView.getBottom());                    c.drawPath(path, mPaint);                }            }        }    }    /**     * check if is one of the last columns     *     * @param position     * @param columnSize     * @return     */    private boolean isLastGridColumn(int position, int columnSize) {        boolean isLast = false;        if ((position + 1) % columnSize == 0) {            isLast = true;        }        return isLast;    }    /**     * check if is the last row of the grid     *     * @param position     * @param itemSize     * @param columnSize     * @return     */    private boolean isLastRowGrid(int position, int itemSize, int columnSize) {        return position / columnSize == (itemSize - 1) / columnSize;    }    public static class Builder {        private Param params;        private Context context;        public Builder(Context context) {            params = new Param();            this.context = context;        }        public RecyclerViewItemDecoration create() {            RecyclerViewItemDecoration recyclerViewItemDecoration = new RecyclerViewItemDecoration();            recyclerViewItemDecoration.setParams(context, params);            return recyclerViewItemDecoration;        }        public Builder mode(int mode) {            params.mode = mode;            return this;        }        public Builder drawableID(int drawableID) {            params.drawableRid = drawableID;            return this;        }        public Builder color(@ColorInt int color) {            params.color = color;            return this;        }        public Builder color(String color) {            if (isColorString(color)) {                params.color = Color.parseColor(color);            }            return this;        }        public Builder thickness(int thickness) {            params.thickness = thickness;            return this;        }        public Builder dashWidth(int dashWidth) {            params.dashWidth = dashWidth;            return this;        }        public Builder dashGap(int dashGap) {            params.dashGap = dashGap;            return this;        }        public Builder lastLineVisible(boolean visible) {            params.lastLineVisible = visible;            return this;        }        public Builder firstLineVisible(boolean visible) {            params.firstLineVisible = visible;            return this;        }        public Builder paddingStart(int padding) {            params.paddingStart = padding;            return this;        }        public Builder paddingEnd(int padding) {            params.paddingEnd = padding;            return this;        }    }    private static class Param {        public int mode = MODE_HORIZONTAL;        public int drawableRid = 0;        public int color = Color.parseColor(DEFAULT_COLOR);        public int thickness;        public int dashWidth = 0;        public int dashGap = 0;        public boolean lastLineVisible;        public boolean firstLineVisible;        public int paddingStart;        public int paddingEnd;    }}

这里不强调怎么使用RecycleView 下面是调用方法

recyclerView. addItemDecoration(new RecyclerViewItemDecoration.Builder(getActivity())        .mode(RecyclerViewItemDecoration.MODE_GRID)        // .dashWidth(8)        //  .dashGap(5)        .thickness(1)        //.drawableID(R.color.line3)        .create());

OK完毕 更多功能自己去挖掘 下面是截图