我想使用Gridview在Android中创建动画。动画将是，当我将列数更改为2〜4使用动画在GridView中更改列数（项目到项目）
我用下面一行以更改列数：我想实现动画这样
If (true)
gridView.setNumColumns(2);
Else
gridView.setNumColumns(4);
：
https://www.youtube.com/watch?v=1NkuChdWA_I
我需要它太，然后我创建了以下类：
/**
* Created by Butzke on 19/05/2017.
*/
public class GridViewAnimated extends GridView {
private int animationDuration = 300, nextColumns;
private boolean animating = false, waitingScroll, shouldWait = true;
private GridViewAnimationListener animationListener;
public GridViewAnimated(Context context) {
super(context);
init();
}
public GridViewAnimated(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public GridViewAnimated(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
@TargetApi(21)
public GridViewAnimated(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
init();
}
@Override
public int computeVerticalScrollOffset() {
return super.computeVerticalScrollOffset();
}
private void init() {
this.setStretchMode(GridView.STRETCH_COLUMN_WIDTH);
}
public void setAnimating(boolean animating) {
this.animating = animating;
}
@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
if (waitingScroll) {
super.onScrollChanged(l, t, oldl, oldt);
if (computeVerticalScrollOffset() == 0) {
setEnabled(true);
waitingScroll = false;
setAnimating(false);
setNumColumns(nextColumns);
}
} else if (!animating) {
super.onScrollChanged(l, t, oldl, oldt);
}
}
public int getAnimationDuration() {
return animationDuration;
}
public void setAnimationDuration(int animationDuration) {
this.animationDuration = animationDuration;
}
public interface GridViewAnimationListener {
void onAnimationStart(Animator animator);
void onAnimationEnd(Animator animator);
void onAnimationCancel(Animator animator);
void onAnimationRepeat(Animator animator);
}
public GridViewAnimationListener getAnimationListener() {
return animationListener;
}
public void setAnimationListener(GridViewAnimationListener animationListener) {this.animationListener = animationListener;}
public void removeAt(int... positions) {
ArrayList<MyInteger> ints = new ArrayList<>();
for (Integer pos : positions) {
ints.add(new MyInteger(pos));
}
Collections.sort(ints);
int lowest = 99999, highest = 0;
for (MyInteger pos : ints) {
lowest = lowest < pos.getValue() ? lowest : pos.getValue();
highest = highest > pos.getValue() ? highest : pos.getValue();
}
if (lowest >= 0 && highest <= getChildCount()) {
ViewsVO originalViews = getOriginalViews();
for (MyInteger pos : ints) {
getAdapter().removeAt(pos.getValue());
}
getAdapter().notifyDataSetChanged();
animateChildViews(originalViews);
}
}
@Override
public void setAdapter(ListAdapter adapter) {
if (adapter instanceof GridViewAnimatedAdapter) {
super.setAdapter(adapter);
} else {
Log.e("GridViewAnimated", "Adapter needs to be instance of GridViewAnimatedAdapter");
Toast.makeText(getContext(), "Adapter needs to be instance of GridViewAnimatedAdapter", Toast.LENGTH_SHORT).show();
}
}
@Override
public GridViewAnimatedAdapter getAdapter() {
return (GridViewAnimatedAdapter) super.getAdapter();
}
@Override
public void setNumColumns(int numColumns) {
if (getAdapter() == null || !getAdapter().hasStableIds() || getChildCount() == 0) {
super.setNumColumns(numColumns);
setAnimating(false);
return;
} else if (animating) {
return;
}
setAnimating(true);
if (computeVerticalScrollOffset() > 0) {
waitingScroll = true;
setEnabled(false);
smoothScrollToPosition(0);
nextColumns = numColumns;
return;
}
ViewsVO originalViews = getOriginalViews();
super.setNumColumns(numColumns);
getAdapter().notifyDataSetChanged();
animateChildViews(originalViews);
}
private ViewsVO getOriginalViews() {
ViewsVO originalViews = new ViewsVO();
for (int i = 0; i < getChildCount(); i++) {
originalViews.addView(getChildAt(i));
}
return originalViews;
}
private void animateChildViews(final ViewsVO originalViews) {
final GridViewAnimated gridView = this;
getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
@Override
public boolean onPreDraw() {
gridView.getViewTreeObserver().removeOnPreDrawListener(this);
ViewsVO newViews = new ViewsVO();
if (Build.VERSION.SDK_INT >= 21) {
for (int i = 0, z = getChildCount() - 1; z >= 0; z--, i++) {
gridView.getChildAt(z).setTranslationZ(i);
}
}
boolean hasFirst = false;
View firstView = null, lastView = null;
float firstHeight = 0, lastHeight = 0;
ViewsVO newViewsFirstTime = new ViewsVO();
for (int i = 0; i < getChildCount(); i++) {
View view = getChildAt(i);
ViewVO nView = newViews.addView(view);
ViewVO oView = originalViews.getView(view.getId());
if (oView != null) {
view.setScaleX(getScaleX(oView, nView));
view.setScaleY(getScaleY(oView, nView));
view.setTranslationX(getTranslateX(oView, nView));
view.setTranslationY(getTranslateY(oView, nView));
if (!hasFirst) {
firstView = view;
firstHeight = oView.getHeight();
hasFirst = true;
}
lastView = view;
lastHeight = oView.getHeight();
animateView(view);
} else {
newViewsFirstTime.addView(nView);
}
}
for (int i = 0; i < newViewsFirstTime.size(); i++) {
try {
View view = newViewsFirstTime.getViews().get(i).getView();
view.getId();
view.setScaleX(view.getId() > firstView.getId() ? firstView.getScaleX() : lastView.getScaleX());
view.setScaleY(view.getId() > firstView.getId() ? firstView.getScaleY() : lastView.getScaleX());
view.setTranslationX(view.getId() > firstView.getId() ? firstView.getTranslationX() : lastView.getTranslationX());
view.setTranslationY(view.getId() > firstView.getId() ? 0 - firstHeight : lastView.getTranslationY() + lastHeight);
animateView(view);
} catch (Exception ex) {
ex.printStackTrace();
}
}
return false;
}
});
}
private void animateView(final View view) {
ViewPropertyAnimator animator = view.animate().setDuration(animationDuration).translationX(0).translationY(0).scaleX(1).scaleY(1).setListener(new Animator.AnimatorListener() {
@Override
public void onAnimationStart(Animator animator) {animationListener.onAnimationStart(animator);}
@Override
public void onAnimationEnd(Animator animator) {
setAnimating(false);
animationListener.onAnimationEnd(animator);
ViewGroup.LayoutParams params = view.getLayoutParams();
params.width = ViewGroup.LayoutParams.MATCH_PARENT;
params.height = ViewGroup.LayoutParams.MATCH_PARENT;
view.setLayoutParams(params);
}
@Override
public void onAnimationCancel(Animator animator) {animationListener.onAnimationCancel(animator);}
@Override
public void onAnimationRepeat(Animator animator) {animationListener.onAnimationRepeat(animator);}
});
if (Build.VERSION.SDK_INT >= 21) {
animator.translationZ(0);
}
}
private float getTranslateX(ViewVO ov, ViewVO nv) {return ov.getPosX() - nv.getPosX() - ((ov.getWidth() < nv.getWidth() ? nv.getWidth() - ov.getWidth() : ov.getWidth() - nv.getWidth()) * (ov.getWidth() < nv.getWidth() ? 0.5f : -0.5f));}
private float getTranslateY(ViewVO ov, ViewVO nv) {return ov.getPosY() - nv.getPosY() - ((ov.getHeight() < nv.getHeight() ? nv.getHeight() - ov.getHeight() : ov.getHeight() - nv.getHeight()) * (ov.getHeight() < nv.getHeight() ? 0.5f : -0.5f));}
private float getScaleY(ViewVO ov, ViewVO nv) {
return ov.getHeight()/nv.getHeight();
}
private float getScaleX(ViewVO ov, ViewVO nv) {
return ov.getWidth()/nv.getWidth();
}
private class ViewsVO {
private ArrayList<ViewVO> views;
private int size() {
return views.size();
}
private ViewsVO() {
views = new ArrayList<>();
}
private ViewVO addView(View view) {
ViewVO v = new ViewVO(view);
addView(v);
return v;
}
private void addView(ViewVO view) {
views.add(view);
}
private ViewVO getView(long id) {
for (ViewVO view : views) {
if (view.getId() == id) {
return view;
}
}
return null;
}
private ArrayList<ViewVO> getViews() {
return views;
}
}
private class ViewVO {
private View view;
private int id;
private float posY;
private float posX;
private float width;
private float height;
private ViewVO(View view) {
this.view = view;
id = view.getId();
posX = view.getLeft();
posY = view.getTop();
width = view.getWidth();
height = view.getHeight();
}
public int getId() {
return id;
}
public View getView() {
return view;
}
private float getWidth() {
return width;
}
private float getHeight() {
return height;
}
private float getPosY() {
return posY;
}
private float getPosX() {
return posX;
}
}
public static class GridViewAnimatedAdapter extends ArrayAdapter {
private List objects;
public GridViewAnimatedAdapter(Context context, int resource, List objects) {
super(context, resource, objects);
this.objects = objects;
}
public void removeAt(int pos) {objects.remove(pos);}
@Override
public boolean hasStableIds() {
return true;
}
public View dealViewToAnimation(View view) {
ViewGroup.LayoutParams params = view.getLayoutParams();
params.width = ViewGroup.LayoutParams.MATCH_PARENT;
params.height = ViewGroup.LayoutParams.MATCH_PARENT;
view.setLayoutParams(params);
return view;
}
}
private class MyInteger implements Comparable<MyInteger> {
private int value;
public MyInteger(int value) {
this.value = value;
}
public int getValue() {
return value;
}
public void setValue(int value) {
this.value = value;
}
@Override
public int compareTo(MyInteger another) {return value > another.getValue() ? -1 : (value == another.getValue() ? 0 : 1);}}
}
一nd使用它很简单， GridView的适配器需要扩展GridViewAnimatedAdapter和： getView（）：为每个视图设置一个ID并在方法getView结束时，需要使用方法dealViewToAnimation完成（视图视图）例如：
@Override
public View getView(int position, View view, ViewGroup parent) {
...
view.setId(images.getId());
...
return dealViewToAnimation(view);
}
您还可以设置一个监听器，动画状态：
gridView.setAnimationListener(new GridViewAnimated.GridViewAnimationListener() {
@Override
public void onAnimationStart(Animator animator) {
mListMenu.setVisible(false);
}
@Override
public void onAnimationEnd(Animator animator) {
mListMenu.setVisible(true);
gridView.setAnimating(false);
}
@Override
public void onAnimationCancel(Animator animator) {}
@Override
public void onAnimationRepeat(Animator animator) {
}
});
有了这个GridView控件能够绘制在列数的变化和动画去除itens的...
列数动画变化：
gridView.setNumColumns(5);
动画效果去除itens的：
gridView.removeAt(2, 7, 4);
gridView.removeAt(2);
当不止一个，无所谓的顺序，该方法将检查订单，并从去除最高到最低，考虑到最高的ID（该图像添加到视图中）是第一个视图...
尽管它没有像GridViewAnimated中的比例动画，但最好使用RecyclerView，GridLayoutManager和DefaultItemAnimator，因为它改变了colu MNS数量和不滚动...
GridLayoutmanager gridLayoutManager = new GridLayoutManager(context, 2);
recyclerView.setLayoutManager(gridLayoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
然后当你需要更改列：
gridLayoutManager.requestSimpleAnimationsInNextLayout();
gridLayoutManager.setSpanCount(newNumberOfColumns);