【发布时间】：2018-06-23 00:49:23
【问题描述】：
我的每一个布局都看起来像嵌入在 Scrollview 中的卡片类型。当我滚动时，如何像弹簧式一样移动卡片然后回到原来的位置。
就像卡片在弹跳一样。在我的布局中，最上面的是ScrollView，下面集成了5到6个布局。
当我滚动时如何将这些添加的布局向上移动一点并到达它的位置？你可以在这里看到一个例子。只看滚动的地方 卡从它的位置移动。只需查看screenshot 注意上下滚动时卡片会像弹簧类型一样移动的滚动，即滚动时卡片之间的间距会减小。如何实现？
在当前应用的CustomScrollView中，它有过度滚动，但我无法实现弹簧式可移动卡片。
这是我应用的代码。
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/coordinatorLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".LaunchActivity">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.mobile.ui.MyImageView
android:id="@+id/backgroundImage_timeline"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/bg_dot_line"
android:scaleType="centerCrop" />
<com.mobile.ui.view.ObservableScrollView
android:id="@+id/scrollView"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".LaunchActivity">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:id="@+id/commonModules"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@id/anotherModule"
android:orientation="vertical">
<com.mobile.ui.FirstModule //this is one layout
android:id="@+id/myFirstModule"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="visible" />
<---second layout-----> and so on..
</RelativeLayout>
</com.mobile.ui.view.ObservableScrollView>
</RelativeLayout>
public class ObservableScrollView extends ScrollView {
private View inner;
private float y;
private Rect normal = new Rect();
private boolean isCount = false;
public interface OnOverScrolledListener {
void onOverScrolled(android.widget.ScrollView scrollView,
int deltaX, int deltaY, boolean clampedX, boolean clampedY);
}
private OnOverScrolledListener mOnOverScrolledListener;
private int mOverScrollByDeltaX;
private int mOverScrollByDeltaY;
@Override protected boolean overScrollBy(int deltaX, int deltaY, int scrollX, int scrollY, int scrollRangeX, int scrollRangeY, int maxOverScrollX, int maxOverScrollY, boolean isTouchEvent) {
this.mOverScrollByDeltaX = deltaX;
this.mOverScrollByDeltaY = deltaY;
final boolean result = super.overScrollBy(deltaX, deltaY, scrollX, scrollY, scrollRangeX, scrollRangeY, maxOverScrollX, maxOverScrollY, isTouchEvent);
return result;
};
@Override
protected void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) {
super.onOverScrolled(scrollX, scrollY, clampedX, clampedY);
if (mOnOverScrolledListener != null && (clampedX || clampedY)) {
mOnOverScrolledListener.onOverScrolled(this, mOverScrollByDeltaX, mOverScrollByDeltaY, clampedX, clampedY);
}
}
public OnOverScrolledListener getOnOverScrolledListener() {
return mOnOverScrolledListener;
}
public void setOnOverScrolledListener(OnOverScrolledListener onOverScrolledListener) {
this.mOnOverScrolledListener = onOverScrolledListener;
}
public ObservableScrollView(Context context, AttributeSet attrs) {
super(context, attrs);
}
@SuppressLint("MissingSuperCall")
@Override
protected void onFinishInflate() {
if (getChildCount() > 0) {
inner = getChildAt(0);
}
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
if (inner != null) {
commOnTouchEvent(ev);
}
return super.onTouchEvent(ev);
}
public void commOnTouchEvent(MotionEvent ev) {
int action = ev.getAction();
switch (action) {
case MotionEvent.ACTION_DOWN:
break;
case MotionEvent.ACTION_UP:
if (isNeedAnimation()) {
animation();
isCount = false;
}
break;
case MotionEvent.ACTION_MOVE:
final float preY = y;
float nowY = ev.getY();
int deltaY = (int) (preY - nowY);
if (!isCount) {
deltaY = 0;
}
y = nowY;
if (isNeedMove()) {
if (normal.isEmpty()) {
normal.set(inner.getLeft(), inner.getTop(),
inner.getRight(), inner.getBottom());
}
inner.layout(inner.getLeft(), inner.getTop() - deltaY / 2,
inner.getRight(), inner.getBottom() - deltaY / 2);
}
isCount = true;
break;
default:
break;
}
}
public void animation() {
TranslateAnimation ta = new TranslateAnimation(0, 0, inner.getTop(),
normal.top);
ta.setDuration(200);
inner.startAnimation(ta);
inner.layout(normal.left, normal.top, normal.right, normal.bottom);
normal.setEmpty();
}
public boolean isNeedAnimation() {
return !normal.isEmpty();
}
public boolean isNeedMove() {
int offset = inner.getMeasuredHeight() - getHeight();
int scrollY = getScrollY();
if (scrollY == 0 || scrollY == offset) {
return true;
}
return false;
}
}
所以我尝试过的替代方案是，
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
scrollView.setOnScrollChangeListener(new View.OnScrollChangeListener() {
@Override
public void onScrollChange(View v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {
View view = (View) scrollView.getChildAt(scrollView.getChildCount() - 1);
int diff = (view.getBottom() - (scrollView.getHeight() + scrollView.getScrollY()));
if(view.getTop()==scrollY){
// reaches the top end
Log.e("scrolled top","scrolling top");
}
// if diff is zero, then the bottom has been reached
if (diff == 0) {
// do stuff L
Log.e("bottom reached","bottom reached");
}
else {
TranslateAnimation animation = new TranslateAnimation(0f, 0f, 0f, -100f); // might need to review the docs
animation.setDuration(500); // set how long you want the animation
animation.setFillAfter(true);
myFirstModule.startAnimation(animation);
mySecondModule.startAnimation(animation);
//till 10..
}
}
});
}
但这在滚动期间没有得到应用。滚动和视图上升后动画有一些延迟，而不是完美的。
【问题讨论】：
标签： android animation android-animation android-scrollview bounce