由于项目上的需要侧滑条目展示收藏按钮,记得之前代码家有写过一个厉害的开源控件 AndroidSwipeLayout 本来准备直接拿来使用,但是看过 issue 发现现在有不少使用者反应有不少的 bug ,而且代码家现在貌似也不进行维护了.故自己实现了一个所要效果的一个控件.因为只是实现我需要的效果,所以大家也能看到,代码里有不少地方我是写死的.希望对大家有些帮助.而且暂时也不需要 AndroidSwipeLayout 大而全的功能,算是变相给自己做的项目精简代码了.

完整示例代码请看:GitHub 地址

主要源码:

public class SwipeLayout extends FrameLayout { public static final int CLOSE = 0; public static final int OPEN = 1; private int mState = CLOSE; private int mWidth; private int mHeight; private float mDownX; private float mDownY; private SwipeListener mSwipeListener; private View mTopView; private View mBottomView; private ViewDragHelper mViewDragHelper; public SwipeLayout(Context context) { this(context, null); } public SwipeLayout(Context context, AttributeSet attrs) { this(context, attrs, 0); } public SwipeLayout(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); mViewDragHelper = ViewDragHelper.create(this, new ViewDragHelper.Callback() { @Override public boolean tryCaptureView(View child, int pointerId) {//只对mTopView进行处理 return child == mTopView; } @Override public int clampViewPositionHorizontal(View child, int left, int dx) {//设置横向滑动的边界(left的值是mTopView左上角点的x坐标值) int newLeft; if (left <= -mBottomView.getMeasuredWidth()) { newLeft = -mBottomView.getMeasuredWidth(); } else if (left >= 0) { newLeft = 0; } else { newLeft = left; } return newLeft; } @Override public int clampViewPositionVertical(View child, int top, int dy) {//因为不需要上下的滑动直接设置为0(top的值是mTopView左上角点的y坐标值) return 0; } @Override public void onViewReleased(View releasedChild, float xvel, float yvel) {//手指松开时会回调该函数 int right = mWidth - releasedChild.getRight();//mTopView右边界距离屏幕右边的距离 int bottomWidth = mBottomView.getMeasuredWidth(); if (right > bottomWidth * 9 / 10) { scrollToLeftEdge(); return; } if (right <= bottomWidth / 10 && right > 0) { scrollToRightEdge(); return; } if (xvel == 0) {//速度为0时单独处理 if (right >= bottomWidth / 2) { scrollToLeftEdge(); } else if (right < bottomWidth / 2) { scrollToRightEdge(); } return; } if (xvel > 0) {//向右滑动后松手 scrollToRightEdge(); } else {//向左滑动后松手 scrollToLeftEdge(); } } }); } @Override public void computeScroll() { if (mViewDragHelper.continueSettling(true)) { invalidate(); } } @Override public boolean onInterceptTouchEvent(MotionEvent ev) { switch (ev.getAction()) { case MotionEvent.ACTION_DOWN: mDownX = ev.getRawX(); mDownY = ev.getRawY(); if (mState == CLOSE) { return true; } break; case MotionEvent.ACTION_MOVE: float distanceX = ev.getRawX() - mDownX; float distanceY = ev.getRawY() - mDownY; float angle; if (distanceX == 0) { angle = 90; } else { angle = (float) Math.toDegrees(Math.atan(Math.abs(distanceY / distanceX))); } if (angle < 45) { return true;//拦截事件交给自己处理滑动 } break; } return mViewDragHelper.shouldInterceptTouchEvent(ev); } @Override public boolean onTouchEvent(MotionEvent ev) { ViewParent viewParent = getParent(); switch (ev.getAction()) { case MotionEvent.ACTION_DOWN: mDownX = ev.getRawX(); mDownY = ev.getRawY(); break; case MotionEvent.ACTION_MOVE: float distanceX = ev.getRawX() - mDownX; float distanceY = ev.getRawY() - mDownY; float angle; if (distanceX == 0) { angle = 90; } else { angle = (float) Math.toDegrees(Math.atan(Math.abs(distanceY / distanceX))); } if (angle < 45 && viewParent != null) { viewParent.requestDisallowInterceptTouchEvent(true);//让父控件不要处理事件,交给子控件 } break; case MotionEvent.ACTION_CANCEL: case MotionEvent.ACTION_UP: if (viewParent != null) { viewParent.requestDisallowInterceptTouchEvent(false); } break; } mViewDragHelper.processTouchEvent(ev); return true; } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { super.onLayout(changed, l, t, r, b); int measureHeight = mBottomView.getMeasuredHeight(); int measureWidth = mBottomView.getMeasuredWidth(); mBottomView.layout(mWidth - measureWidth, (mHeight - measureHeight) / 2, mWidth, mHeight + measureHeight / 2);//靠右边界垂直居中 if (mState == OPEN) { mTopView.layout(-measureWidth, 0, mTopView.getMeasuredWidth() - measureWidth, mTopView.getMeasuredHeight()); } } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); mWidth = w; mHeight = h; } @Override protected void onFinishInflate() { super.onFinishInflate(); if (getChildCount() != 2) { throw new IllegalStateException("only and should contain two child view"); } View bottomView = getChildAt(0); if (!(bottomView instanceof ViewGroup)) { throw new IllegalStateException("sideslip menu should be contained by a viewgroup"); } mBottomView = bottomView; mTopView = getChildAt(1); } //回滚到左边(只能在onViewReleased里使用该方法) private void scrollToLeftEdge() { mViewDragHelper.settleCapturedViewAt(-mBottomView.getMeasuredWidth(), 0); invalidate(); mState = OPEN; if (mSwipeListener != null) { mSwipeListener.onOpenListener(this); } } //回滚到右边(只能在onViewReleased里使用该方法) private void scrollToRightEdge() { mViewDragHelper.settleCapturedViewAt(0, 0); invalidate(); mState = CLOSE; } public void smoothClose() { mViewDragHelper.smoothSlideViewTo(mTopView, 0, 0); invalidate(); mState = CLOSE; } public int getState() { return mState; } public void setState(int state) { mState = state; invalidate(); } public interface SwipeListener { void onOpenListener(SwipeLayout swipeLayout); } public void setSwipeListener(SwipeListener mSwipeListener) { this.mSwipeListener = mSwipeListener; } }

效果图

以上所述是小编给大家介绍的Android 中 SwipeLayout一个展示条目底层菜单的侧滑控件源码解析，希望对大家有所帮助，如果大家有任何疑问请给我们留言，小编会及时回复大家的。在此也非常感谢大家对查字典教程网的支持！