我在我的项目中使用了Vertical Viewpager。
但是有一些问题，
当网页上有大量的onclick（）事件时，滚动太难了
投掷活动不会更改页面
我尝试使用手势检测器，但是没有转换就更快地更改了页面（没有调用transformPage（））
当我滚动页面时，有时onclick（）事件也会被触发
所以我在use Recyclerview as Viewpager的帮助下决定 PagerSnapHelper 。
工作正常。但问题是，
当项目发生变化时如何进行过渡或动画（就像我一样） 在ViewPager中做过）
例如，Viewpager中的缩小转换或堆栈转换。
我尝试了stackLayoutManager但滚动并尝试了related link需要更多时间。它不起作用。
我研究过两个问题如何降低viewpager的滚动速度和如何在recyclerview中进行动画。我没有得到它的解决方案。
任何人都可以帮助我!!!是否可能或我需要使用任何其他小部件。
我尝试了＃ADM的建议，它运行正常但doesn't support PagerSnapHelper.
我在上面的链接中更改了stacklayout manager，但它不支持scrollToPosition（）和PagerSnapHelper。
代码：
public class StackLayoutManager extends LinearLayoutManager {
private static final String TAG = "StackLayoutManager";
//the space unit for the stacked item
private int mSpace = 0;
/**
* the offset unit,deciding current position(the sum of {@link #mItemWidth} and {@link #mSpace})
*/
private int mUnit;
//item width
private int mItemWidth;
private int mItemHeight;
//the counting variable ,record the total offset including parallex
private int mTotalOffset;
//record the total offset without parallex
private int mRealOffset;
private ObjectAnimator animator;
private int animateValue;
private RecyclerView.Recycler recycler;
private int lastAnimateValue;
private int initialOffset;
private boolean initial;
private int mMinVelocityX;
private VelocityTracker mVelocityTracker = VelocityTracker.obtain();
private int pointerId;
private Method sSetScrollState;
RecyclerView recyclerView;
public StackLayoutManager(Context context) {
super(context, VERTICAL, false);
setAutoMeasureEnabled(true);
}
@Override
public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) {
this.recycler = recycler;
detachAndScrapAttachedViews(recycler);
//got the mUnit basing on the first child,of course we assume that all the item has the same size
View anchorView = recycler.getViewForPosition(0);
measureChildWithMargins(anchorView, View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
mItemWidth = anchorView.getMeasuredWidth();
mItemHeight = getDecoratedMeasuredHeight(anchorView);
mUnit = mItemHeight;
//because this method will be called twice
initialOffset = mUnit;
mMinVelocityX = ViewConfiguration.get(anchorView.getContext()).getScaledMinimumFlingVelocity();
fill(recycler, 0);
}
@Override
public void onLayoutCompleted(RecyclerView.State state) {
super.onLayoutCompleted(state);
if (!initial) {
fill(recycler, initialOffset, false);
initial = true;
}
}
@Override
public void onAdapterChanged(RecyclerView.Adapter oldAdapter, RecyclerView.Adapter newAdapter) {
initial = false;
mTotalOffset = mRealOffset = 0;
}
private int fill(RecyclerView.Recycler recycler, int dy, boolean apply) {
return fillFromTop(recycler, dy);
}
public int fill(RecyclerView.Recycler recycler, int dy) {
return fill(recycler, dy, true);
}
private int fillFromTop(RecyclerView.Recycler recycler, int dy) {
if (mTotalOffset + dy < 0 || (mTotalOffset + dy + 0f) / mUnit > getItemCount() - 1)
return 0;
detachAndScrapAttachedViews(recycler);
mTotalOffset += dy;
int count = getChildCount();
for (int i = 0; i < count; i++) {
View child = getChildAt(i);
if (recycleVertically(child, dy))
removeAndRecycleView(child, recycler);
}
int curPos = mTotalOffset / mUnit;
int leavingSpace = getHeight() - (left(curPos) + mUnit);
int itemCountAfterBaseItem = leavingSpace / mUnit + 2;
int e = curPos + itemCountAfterBaseItem;
int start = curPos - 1 >= 0 ? curPos - 1 : 0;
int end = e >= getItemCount() ? getItemCount() - 1 : e;
int left = getWidth() / 2 - mItemWidth / 2;
//layout views
for (int i = start; i <= end; i++) {
View view = recycler.getViewForPosition(i);
float alpha = alpha(i);
addView(view);
measureChildWithMargins(view, 0, 0);
int top = (left(i) /* - ( 1 - scale ) * view.getMeasuredHeight() */ );
int right = view.getMeasuredWidth() + left;
int bottom = view.getMeasuredHeight() + top;
layoutDecoratedWithMargins(view, left, top, right, bottom);
view.setAlpha(alpha);
view.setScaleY(1);
view.setScaleX(1);
}
return dy;
}
private View.OnTouchListener mTouchListener = new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
mVelocityTracker.addMovement(event);
if (event.getAction() == MotionEvent.ACTION_DOWN) {
if (animator != null && animator.isRunning())
animator.cancel();
pointerId = event.getPointerId(0);
}
if (event.getAction() == MotionEvent.ACTION_UP) {
if (v.isPressed())
v.performClick();
mVelocityTracker.computeCurrentVelocity(1000, 14000);
float xVelocity = mVelocityTracker.getYVelocity(pointerId);
int o = mTotalOffset % mUnit;
int scrollX;
if (Math.abs(xVelocity) < mMinVelocityX && o != 0) {
if (o >= mUnit / 2)
scrollX = mUnit - o;
else
scrollX = -o;
Log.d("scrollx","from scroll");
Log.d("scrollx", "" + scrollX);
brewAndStartAnimator(300, (int) (scrollX));
}
}
return false;
}
};
private RecyclerView.OnFlingListener mOnFlingListener = new RecyclerView.OnFlingListener() {
@Override
public boolean onFling(int velocityX, int velocityY) {
int o = mTotalOffset % mUnit;
int s = mUnit - o;
int scrollX;
int vel = absMax(velocityX, velocityY);
if (vel > 0) {
scrollX = s;
} else
scrollX = -o;
Log.d("scrollx","from fling");
Log.d("scrollx",""+scrollX);
brewAndStartAnimator(100, scrollX);
// setScrollStateIdle();
return true;
}
};
private int absMax(int a, int b) {
if (Math.abs(a) > Math.abs(b))
return a;
else return b;
}
@Override
public void onAttachedToWindow(RecyclerView view) {
super.onAttachedToWindow(view);
this.recyclerView=view;
view.setOnTouchListener(mTouchListener);
view.setOnFlingListener(mOnFlingListener);
}
private void brewAndStartAnimator(int dur, int finalX) {
animator = ObjectAnimator.ofInt(StackLayoutManager.this, "animateValue", 0, finalX);
animator.setDuration(dur);
animator.start();
animator.addListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
lastAnimateValue = 0;
recyclerView.scrollToPosition(findFirstCompletelyVisibleItemPosition());
}
@Override
public void onAnimationCancel(Animator animation) {
lastAnimateValue = 0;
recyclerView.smoothScrollToPosition(findFirstCompletelyVisibleItemPosition());
}
});
}
private float alpha(int position) {
float alpha;
int curPos = mTotalOffset / mUnit;
float n = (mTotalOffset + .0f) / mUnit;
if (position > curPos)
alpha = 1.0f;
else {
alpha = 1 - (n - position) / 1;
}
return alpha <= 0.001f ? 0 : alpha;
}
@Override
public void scrollToPosition(int pos)
{
scrollToPositionWithOffset(pos, 0);
}
private int left(int position) {
int curPos = mTotalOffset / mUnit;
int tail = mTotalOffset % mUnit;
float n = (mTotalOffset + .0f) / mUnit;
float x = n - curPos;
return ltr(position, curPos, tail, x);
}
private int ltr(int position, int curPos, int tail, float x) {
int left;
if (position <= curPos) {
if (position == curPos) {
left = (int) (mSpace * (1 - x));
} else {
left = (int) (mSpace * (1 - x - (curPos - position)));
}
} else {
if (position == curPos + 1)
left = mSpace + mUnit - tail;
else {
int baseStart = (int) (mUnit + mUnit);
left = (int) (baseStart + (position - curPos - 2) * mUnit - (position - curPos - 2) * (mUnit));
if (BuildConfig.DEBUG)
Log.i(TAG, "ltr: curPos " + curPos + " pos:" + position + " left:" + left + " baseStart" + baseStart + " curPos+1:" + left(curPos + 1));
}
left = left <= 0 ? 0 : left;
}
return left;
}
@SuppressWarnings("unused")
public void setAnimateValue(int animateValue) {
this.animateValue = animateValue;
int dy = this.animateValue - lastAnimateValue;
fill(recycler, dy, false);
lastAnimateValue = animateValue;
}
@SuppressWarnings("unused")
public int getAnimateValue() {
return animateValue;
}
private boolean recycleVertically(View view, int dy) {
return view != null && (view.getTop() - dy < 0 || view.getBottom() - dy > getHeight());
}
@Override
public int scrollVerticallyBy(int dy, RecyclerView.Recycler recycler, RecyclerView.State state) {
return fill(recycler, dy);
}
@Override
public boolean canScrollHorizontally() {
return false;
}
@Override
public boolean canScrollVertically() {
return true;
}
@Override
public RecyclerView.LayoutParams generateDefaultLayoutParams() {
return new RecyclerView.LayoutParams(RecyclerView.LayoutParams.MATCH_PARENT, RecyclerView.LayoutParams.MATCH_PARENT);
}
@SuppressWarnings("unused")
public interface CallBack {
float scale(int totalOffset, int position);
float alpha(int totalOffset, int position);
float left(int totalOffset, int position);
}
}
如果使用recyclerview无法实现，请帮我解决使用VerticalViewPager的问题。我试过设置字段值，但它不起作用。
try {
Class cls = this.getClass().getSuperclass();
Field distanceField = cls.getDeclaredField("mFlingDistance");
distanceField.setAccessible(true);
distanceField.setInt(this, distanceField.getInt(this)/2);
}catch (Exception ignored) {
Log.d("error", ignored.toString());
}
try {
Class cls = this.getClass().getSuperclass();
Field minVelocityField = cls.getDeclaredField("mMinimumVelocity");
minVelocityField.setAccessible(true);
minVelocityField.setInt(this, minVelocityField.getInt(this) /2);
} catch (Exception ignored) {
Log.d("error", ignored.toString());
}
try {
Class cls = this.getClass().getSuperclass();
Field maxVelocityField = cls.getDeclaredField("mMaximumVelocity");
maxVelocityField.setAccessible(true);
maxVelocityField.setInt(this, maxVelocityField.getInt(this)/2);
}catch (Exception ignored) {
Log.d("error", ignored.toString());
}
答案 0 :(得分：1)
试试这个
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import java.util.ArrayList;
import android.support.animation.DynamicAnimation;
import android.support.animation.FlingAnimation;
public class MainActivity extends AppCompatActivity {
CustomVerticalViewPager viewPager;
ArrayList<DataModel> arrayList = new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initArray();
viewPager = findViewById(R.id.viewPager);
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
FlingAnimation fling = new FlingAnimation(viewPager, DynamicAnimation.SCROLL_X);
}
@Override
public void onPageSelected(int position) {
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
CustomAdapter adapter = new CustomAdapter(this, arrayList);
viewPager.setAdapter(adapter);
}
private void initArray() {
for (int i = 0; i < 10; i++) {
DataModel dataModel = new DataModel();
dataModel.setTitle("Title item No :- " + i);
dataModel.setContent(" Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras auctor blandit dignissim. Suspendisse id lorem nulla. Proin urna lacus, posuere sed lacus a, dapibus consectetur neque. Donec in metus sagittis, consequat tellus eget, consequat ex. Interdum et malesuada fames ac ante ipsum primis in faucibus. Donec dui nisi, scelerisque eu nunc id, aliquet sagittis leo. Nunc ac ornare diam. Vestibulum sed elit euismod, ornare metus a, convallis ipsum. Nulla aliquam mi enim, porttitor commodo lacus dictum cursus. Phasellus sed eros sagittis, feugiat sapien ac, accumsan odio. In posuere congue lorem, quis pharetra mi tincidunt et. Nam tincidunt erat eu dapibus faucibus.\n" +
"\n");
arrayList.add(dataModel);
}
}
}
<强>布局
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<com.example.nilesh.testapp.CustomVerticalViewPager
android:layout_width="match_parent"
android:id="@+id/viewPager"
android:layout_height="match_parent" />
</LinearLayout>
<强> CustomVerticalViewPager
import android.content.Context;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
public class CustomVerticalViewPager extends ViewPager {
private GestureDetector gestureDetector;
public boolean isScrollEvent;
public CustomVerticalViewPager(Context context) {
super(context);
init();
}
public CustomVerticalViewPager(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
private void init() {
gestureDetector=new GestureDetector(getContext(),new GestureListener());
setPageTransformer(true, new VerticalPageTransformer());
setOverScrollMode(OVER_SCROLL_NEVER);
try {
Field mScroller;
mScroller = ViewPager.class.getDeclaredField("mScroller");
mScroller.setAccessible(true);
FixedSpeedScroller scroller = new FixedSpeedScroller(getContext(), new DecelerateInterpolator());
scroller.setScrollDuration(250);
mScroller.set(this, scroller);
} catch (Exception e) {}
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
return gestureDetector.onTouchEvent((ev));
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
boolean res= gestureDetector.onTouchEvent((ev));
if((ev.getAction() == MotionEvent.ACTION_CANCEL ||ev.getAction()==MotionEvent.ACTION_UP)) {
if(isScrollEvent) {
try {
endFakeDrag();
} catch (Exception e) {}
}
return true;
}
// Log.d("event", "ontouch " + res);
return res;
}
private class FixedSpeedScroller extends Scroller {
private int mDuration = 500;
public FixedSpeedScroller(Context context) {
super(context);
}
public FixedSpeedScroller(Context context, Interpolator interpolator) {
super(context, interpolator);
}
public FixedSpeedScroller(Context context, Interpolator interpolator, boolean flywheel) {
super(context, interpolator, flywheel);
}
public void setScrollDuration(int duration) {
mDuration = duration;
}
@Override
public void startScroll(int startX, int startY, int dx, int dy, int duration) {
super.startScroll(startX, startY, dx, dy, mDuration);
}
@Override
public void startScroll(int startX, int startY, int dx, int dy) {
super.startScroll(startX, startY, dx, dy, mDuration);
}
}
private final class GestureListener extends GestureDetector.SimpleOnGestureListener {
@Override
public boolean onSingleTapUp(MotionEvent e) {
isScrollEvent=false;
// Log.d("touch","singletap");
return false;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
// Log.d("touch","fling");
isScrollEvent=false;
try {
float diffY = e2.getY() - e1.getY();
if (diffY > 20) {
onSwipeDown();
return false;
} else if(diffY<-20){
onSwipeUp();
return false;
}
else
{
endFakeDrag();
}
} catch (Exception exception) {
exception.printStackTrace();
}
return false;
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2,
float distanceX, float distanceY) {
// Log.d("touch", "scroll" + " " + distanceX);
beginFakeDrag();
fakeDragBy(-distanceY);
isScrollEvent=true;
return true;
}
}
public void onSwipeUp() {
setCurrentItem(getCurrentItem() + 1);
}
public void onSwipeDown() {
setCurrentItem(getCurrentItem() - 1);
}
}
<强> CustomAdapter
import android.content.Context;
import android.support.v4.view.PagerAdapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
public class CustomAdapter extends PagerAdapter {
Context context;
ArrayList<DataModel> arrayList = new ArrayList<>();
LayoutInflater mLayoutInflater;
public CustomAdapter(Context context, ArrayList<DataModel> arrayList) {
this.context = context;
this.arrayList = arrayList;
mLayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
@Override
public int getCount() {
return arrayList.size();
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view == ((LinearLayout) object);
}
@Override
public Object instantiateItem(ViewGroup container, final int position) {
View itemView = mLayoutInflater.inflate(R.layout.custom_layout, container, false);
TextView tvTitle = itemView.findViewById(R.id.tvTitle);
TextView tvContent = itemView.findViewById(R.id.tvContent);
tvContent.setText(arrayList.get(position).getContent());
tvTitle.setText(arrayList.get(position).getTitle());
tvTitle.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(context, "clicked position :" + position + " " + arrayList.get(position).getTitle(), Toast.LENGTH_SHORT).show();
}
});
container.addView(itemView);
return itemView;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((LinearLayout) object);
}
}
<强>的DataModel
public class DataModel {
String title, content;
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getContent() {
return content;
}
public void setContent(String content) {
this.content = content;
}
}
<强> custom_layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/tvTitle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="5dp"
android:text="Nilesh"
android:textColor="#000"
android:textSize="20sp"
android:textStyle="bold" />
<TextView
android:id="@+id/tvContent"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
希望这有帮助
使用Move views using a fling animation
基于Fling的动画使用与物体速度成比例的摩擦力。使用它来设置对象属性的动画，并希望逐渐结束动画。它有一个初始动量，主要是从手势速度接收，并逐渐减慢。当动画的速度足够低以至于在设备屏幕上没有任何可见的变化时，动画就会结束。