利用Scroller来写一个侧滑布局效果如下:
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1.自定义一个Viewgroup在构造方法初始化参数
mScroller = new Scroller(context);
//滑动临界值
ViewConfiguration viewConfiguration = ViewConfiguration.get(context);
mTouchSlop = ViewConfigurationCompat.getScaledPagingTouchSlop(viewConfiguration);
2.在onMeasure方法中测量子孩子大小
if (!mIsMeasure) {
for (int i = 0; i < getChildCount(); i++) {
View view = getChildAt(i);
measureChild(view, widthMeasureSpec, heightMeasureSpec);
}
mIsMeasure = true;
}
3.在onLayout布局中初始化子孩子的位置里面有三个view分别是文本内容,置顶以及删除
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
for (int i = 0; i < getChildCount(); i++) {
View view = getChildAt(i);
if (i == 0) {
mTextWidth = view.getMeasuredWidth();
view.layout(0, 0, mTextWidth, view.getMeasuredHeight());
} else if (i == 1) {
//置顶文本的宽度
mStickWidth = view.getMeasuredWidth();
view.layout(mTextWidth, 0, mTextWidth + mStickWidth, view.getMeasuredHeight());
} else if (i == 2) {
//删除文本的宽度
mDeleteWidth = view.getMeasuredWidth();
view.layout(mTextWidth + mStickWidth, 0, mTextWidth + mStickWidth + mDeleteWidth, view.getMeasuredHeight());
}
}
}
4.在onInterceptTouchEvent方法中处理滑动事件,如果是横向滑动我们就拦截事件自己去处理事件
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
mDownX = (int) ev.getRawX();
break;
case MotionEvent.ACTION_MOVE:
mMovex = (int) ev.getRawX();
float diff = Math.abs(mMovex - mDownX);
// 当手指拖动值大于TouchSlop值时，认为应该进行滚动，拦截子控件的事件
mLastMove = mMovex;
if (diff > mTouchSlop) {
return true;
}
break;
}
return super.onInterceptTouchEvent(ev);
}
5.在onTouchEvent方法中处理滑动事件,用ScrollBy方法来移动控件,移动过程中对移动范围进行限制
move事件中:
mMovex = (int) event.getX();
scrollBy(mLastMove - mMovex, 0);
if (getScrollX() <= 0) {
scrollTo(0, 0);
return true;
}
if (getScrollX() >= mDeleteWidth + mStickWidth) {
scrollTo(mDeleteWidth + mStickWidth, 0);
return true;
}
mLastMove = mMovex;
当手指抬起的时候根据移动的位置来判断是否是打开还是关闭getScrollX()方法可以得到移动的x值,大于置顶和删除文本宽度一半时就是打开状态否则就是关闭
if (getScrollX() >= mDeleteWidth) {//open
dx = mDeleteWidth + mStickWidth - getScrollX();
if (mOnStateChangeListener != null) {
mOnStateChangeListener.onOpen(this);
}
} else {//close
dx = 0 - getScrollX();
mOnStateChangeListener.onClose(this);
}
mScroller.startScroll(getScrollX(), 0, dx, 0);
invalidate();
6.在配合Recycleview使用的时候要注意的地方:
在onTouchEvent方法中move事件要请求父控件不要拦截否则收不到up事件
//请求父容器不要拦截事件
getParent().requestDisallowInterceptTouchEvent(true);
在侧滑时一个条目时其他条目都要关闭这里利用adapter进行对当前滑动条目的记录和已经打开的条目记录,然后在move的时候进行判断
case MotionEvent.ACTION_MOVE:
if (getAdapter().getOpenView() != null && getAdapter().getOpenView() != this) {
getAdapter().getOpenView().close();
getAdapter().setOpenView(null);
return true;
}
if (getAdapter().getCurrentDeleteView() !=null && getAdapter().getCurrentDeleteView() != this) {
return true;
}
完整代码:
public class DeleteView extends ViewGroup {
private Scroller mScroller;
private int mDownX;
private int mMovex;
private int mTouchSlop;
private boolean mIsMeasure = false;
private int mTextWidth;
private int mStickWidth;
private int mDeleteWidth;
private int mLastMove;
public DeleteView(Context context) {
this(context, null);
}
public DeleteView(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
mScroller = new Scroller(context);
//滑动临界值
ViewConfiguration viewConfiguration = ViewConfiguration.get(context);
mTouchSlop = ViewConfigurationCompat.getScaledPagingTouchSlop(viewConfiguration);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (!mIsMeasure) {
for (int i = 0; i < getChildCount(); i++) {
View view = getChildAt(i);
measureChild(view, widthMeasureSpec, heightMeasureSpec);
}
mIsMeasure = true;
}
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
for (int i = 0; i < getChildCount(); i++) {
View view = getChildAt(i);
if (i == 0) {
mTextWidth = view.getMeasuredWidth();
view.layout(0, 0, mTextWidth, view.getMeasuredHeight());
} else if (i == 1) {
mStickWidth = view.getMeasuredWidth();
view.layout(mTextWidth, 0, mTextWidth + mStickWidth, view.getMeasuredHeight());
} else if (i == 2) {
mDeleteWidth = view.getMeasuredWidth();
view.layout(mTextWidth + mStickWidth, 0, mTextWidth + mStickWidth + mDeleteWidth, view.getMeasuredHeight());
}
}
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
mDownX = (int) ev.getRawX();
break;
case MotionEvent.ACTION_MOVE:
mMovex = (int) ev.getRawX();
float diff = Math.abs(mMovex - mDownX);
// 当手指拖动值大于TouchSlop值时，认为应该进行滚动，拦截子控件的事件
mLastMove = mMovex;
if (diff > mTouchSlop) {
return true;
}
break;
}
return super.onInterceptTouchEvent(ev);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_MOVE:
if (getAdapter().getOpenView() != null && getAdapter().getOpenView() != this) {
getAdapter().getOpenView().close();
getAdapter().setOpenView(null);
return true;
}
if (getAdapter().getCurrentDeleteView() !=null && getAdapter().getCurrentDeleteView() != this) {
return true;
}
getAdapter().setCurrentDeleteView(this);
//请求父容器不要拦截事件
getParent().requestDisallowInterceptTouchEvent(true);
mMovex = (int) event.getX();
scrollBy(mLastMove - mMovex, 0);
if (getScrollX() <= 0) {
scrollTo(0, 0);
return true;
}
if (getScrollX() >= mDeleteWidth + mStickWidth) {
scrollTo(mDeleteWidth + mStickWidth, 0);
return true;
}
mLastMove = mMovex;
break;
case MotionEvent.ACTION_UP:
LogUtils.LogE("up");
int dx = 0;
if (getScrollX() >= mDeleteWidth) {//open
dx = mDeleteWidth + mStickWidth - getScrollX();
if (mOnStateChangeListener != null) {
mOnStateChangeListener.onOpen(this);
}
} else {//close
dx = 0 - getScrollX();
mOnStateChangeListener.onClose(this);
}
mScroller.startScroll(getScrollX(), 0, dx, 0);
invalidate();
getAdapter().setCurrentDeleteView(null);
break;
}
return true;
}
@Override
public void computeScroll() {
if (mScroller.computeScrollOffset()) {
scrollTo(mScroller.getCurrX(), mScroller.getCurrY());
invalidate();
}
}
public interface onStateChangeListener {
void onOpen(DeleteView deleteView);
void onClose(DeleteView deleteView);
}
private onStateChangeListener mOnStateChangeListener;
public void setOnStateChangeListener(onStateChangeListener onStateChangeListener) {
mOnStateChangeListener = onStateChangeListener;
}
public void open() {
scrollTo(mStickWidth + mDeleteWidth, 0);
}
public void close() {
scrollTo(0, 0);
}
/**
* 得到适配器
*
* @return
*/
private DeleteAdapter getAdapter() {
return (DeleteAdapter) ((RecyclerView) getParent()).getAdapter();
}
Adapter代码：
public class DeleteAdapter extends RecyclerView.Adapter {
private List<CartModel> mDatas;
private DeleteView mDeleteView;
private DeleteView mOpenView;
public DeleteAdapter(List<CartModel> list) {
mDatas = list;
}
public void setData(List<CartModel> list) {
mDatas = list;
notifyDataSetChanged();
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_delete, parent, false);
MyHolder holder = new MyHolder(view);
return holder;
}
@Override
public void onBindViewHolder(final RecyclerView.ViewHolder holder, final int position) {
MyHolder myHolder = (MyHolder) holder;
myHolder.setItem(position);
((DeleteView) holder.itemView).setOnStateChangeListener(new DeleteView.onStateChangeListener() {
@Override
public void onOpen(DeleteView deleteView) {
mOpenView = deleteView;
}
@Override
public void onClose(DeleteView deleteView) {
}
});
myHolder.delete.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(v.getContext(),"删除"+position,Toast.LENGTH_SHORT).show();
mDatas.remove(position);
getOpenView().close();
notifyDataSetChanged();
}
});
myHolder.stick.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
CartModel cartModel = mDatas.get(position);
Toast.makeText(v.getContext(),"置顶"+position,Toast.LENGTH_SHORT).show();
mDatas.remove(cartModel);
mDatas.add(0,cartModel);
getOpenView().close();
notifyDataSetChanged();
}
});
}
/**
* 得到当前滑动的view
*
* @return
*/
public DeleteView getCurrentDeleteView() {
return mDeleteView;
}
/**
* 得到当前滑动的view
*
* @return
*/
public void setCurrentDeleteView(DeleteView deleteView) {
this.mDeleteView = deleteView;
}
public DeleteView getOpenView() {
return mOpenView;
}
public void setOpenView(DeleteView openView) {
mOpenView = openView;
}
@Override
public int getItemCount() {//加的一是脚步局
return mDatas.size();
}
class MyHolder extends RecyclerView.ViewHolder {
TextView title;
TextView stick;
TextView delete;
public MyHolder(View itemView) {
super(itemView);
title = itemView.findViewById(R.id.tv_title);
stick = itemView.findViewById(R.id.tv_stick);
delete = itemView.findViewById(R.id.tv_delete);
}
public void setItem(int position) {
CartModel cartModel = mDatas.get(position);
title.setText(cartModel.getName());
}
}
}
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