想要实现无限轮播,一直向左滑动,当到最后一个view时,会滑动到第一个,无限…
可以自己写ViewPager然后加handler先实现自动滚动,当然这里我为了项目的进度直接使用了Trinea的Android-auto-scroll-view-pager库,网址:点击进入github 引用库compile('cn.trinea.android.view.autoscrollviewpager:android-auto-scroll-view-pager:1.1.2') {
exclude module: 'support-v4'之后
1布局为
2 构建PagerAdapter
继承自RecyclingPagerAdapter (后面会贴出来源码)
`public class Indicator1Adapter extends RecyclingPagerAdapter {
private List imageIdList;
Context context;
//是否循环(创造构造方法,在activity里设置是否)
//集合大小
private int size;
public Indicator1Adapter(List mData, Context context) {
this.imageIdList = mData;
this.context = context;
this.size = mData.size();
isInfiniteLoop = false;
}
@Override
public int getCount() {
//是:最大(让集合的长度无限,从而模拟无限循环) 否,集合长度
return isInfiniteLoop ? Integer.MAX_VALUE : imageIdList.size();
}
public boolean isInfiniteLoop() {
return isInfiniteLoop;
}
public Indicator1Adapter setInfiniteLoop(boolean isInfiniteLoop) {
this.isInfiniteLoop = isInfiniteLoop;
return this;
}
private int getPosition(int position) {
return isInfiniteLoop ? position % size : position;
}
@Override
public View getView(int position, View view, ViewGroup container) {
ViewHolder holder;
if (view == null) {
holder = new ViewHolder();
view = holder.imageView = new ImageView(context);
view.setTag(holder);
} else {
holder = (ViewHolder)view.getTag();
}
holder.imageView.setImageResource(imageIdList.get(getPosition(position)));
holder.imageView.setScaleType(ImageView.ScaleType.FIT_XY);
return view;
}
private static class ViewHolder {
ImageView imageView;
}
}
3 在activity里或者fragment里就可以设置ViewPager
定义的成员变量:
//viewpager1 @BindView(R.id.viewpager1) AutoScrollViewPager mPager1; //承载小点点的控件容器(布局里有) @BindView(R.id.ll_dot1) LinearLayout mLlDot1;
Indicator1Adapter adapter1 = new Indicator1Adapter( mData,act).setInfiniteLoop(true);//开启无限循环 mPager1.setAdapter(adapter1); mPager1.setInterval(PLAY_TIME);//轮播时间间隔 mPager1.startAutoScroll();//开启自动轮播 mPager1.setCurrentItem(Integer.MAX_VALUE / 2 - Integer.MAX_VALUE / 2 % mData.size());
然后你嫌弃官方的换图间隔时间太短,一闪而过,可以通过反射 设置
//通过反射让滚动速度为自己的喜好的(这里设为1.2s)
try {
Field field = ViewPager.class.getDeclaredField("mScroller");
field.setAccessible(true);
FixedSpeedScroller scroller = new FixedSpeedScroller(mPager1.getContext(),
new AccelerateInterpolator());
field.set(mPager1, scroller);
scroller.setmDuration(1200);
} catch (Exception e) {
Log.e(TAG, "Exception", e);
}
4 然后我们的小点点还没有使用呢
这里我写了方法:
private void setOvalLayout1() {
for (int i = 0; i < mData.size(); i++) {
mLlDot1.addView(inflater.inflate(R.layout.dot, null));
}
// 默认显示第一页
mLlDot1.getChildAt(0).findViewById(R.id.v_dot)
.setBackgroundResource(R.drawable.dot_selected);
mPager1.addonPageChangeListener(new ViewPager.onPageChangeListener() {
public void onPageSelected(int position) {
//遍历图片数组
// Toast.makeText(act, "position"+position, Toast.LENGTH_SHORT).show();
for (int i = 0; i < mData.size(); i++) {
if(i==position%mData.size()){
// 圆点选中
mLlDot1.getChildAt(position%mData.size())
.findViewById(R.id.v_dot)
.setBackgroundResource(R.drawable.dot_selected);
}else{
// 取消圆点选中
mLlDot1.getChildAt(curIndex1%mData.size())
.findViewById(R.id.v_dot)
.setBackgroundResource(R.drawable.dot_normal);
}
}
curIndex1 = position;
}
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
public void onPageScrollStateChanged(int arg0) {
}
});
}
别忘了重写
@Override
public void onPause() {
super.onPause();
// stop auto scroll when onPause
mPager1.stopAutoScroll();
}
@Override
public void onResume() {
super.onResume();
// start auto scroll when onResume
mPager1.startAutoScroll();
}
好了,无限循环自动轮播,完成了.
5点点布局:
6 点点的background
dot_normal.xml
dot_selected.xml
RecyclingPagerAdapter的源码依赖RecycleBin类,一并贴出来
public class RecycleBin {
private View[] activeViews = new View[0];
private int[] activeViewTypes = new int[0];
private SparseArray[] scrapViews;
private int viewTypeCount;
private SparseArray currentScrapViews;
public void setViewTypeCount(int viewTypeCount) {
if (viewTypeCount < 1) {
throw new IllegalArgumentException("Can't have a viewTypeCount < 1");
}
//noinspection unchecked
SparseArray[] scrapViews = new SparseArray[viewTypeCount];
for (int i = 0; i < viewTypeCount; i++) {
scrapViews[i] = new SparseArray();
}
this.viewTypeCount = viewTypeCount;
currentScrapViews = scrapViews[0];
this.scrapViews = scrapViews;
}
protected boolean shouldRecycleViewType(int viewType) {
return viewType >= 0;
}
View getScrapView(int position, int viewType) {
if (viewTypeCount == 1) {
return retrieveFromScrap(currentScrapViews, position);
} else if (viewType >= 0 && viewType < scrapViews.length) {
return retrieveFromScrap(scrapViews[viewType], position);
}
return null;
}
void addScrapView(View scrap, int position, int viewType) {
if (viewTypeCount == 1) {
currentScrapViews.put(position, scrap);
} else {
scrapViews[viewType].put(position, scrap);
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
scrap.setAccessibilityDelegate(null);
}
}
void scrapActiveViews() {
final View[] activeViews = this.activeViews;
final int[] activeViewTypes = this.activeViewTypes;
final boolean multipleScraps = viewTypeCount > 1;
SparseArray scrapViews = currentScrapViews;
final int count = activeViews.length;
for (int i = count - 1; i >= 0; i--) {
final View victim = activeViews[i];
if (victim != null) {
int whichScrap = activeViewTypes[i];
activeViews[i] = null;
activeViewTypes[i] = -1;
if (!shouldRecycleViewType(whichScrap)) {
continue;
}
if (multipleScraps) {
scrapViews = this.scrapViews[whichScrap];
}
scrapViews.put(i, victim);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
victim.setAccessibilityDelegate(null);
}
}
}
pruneScrapViews();
}
private void pruneScrapViews() {
final int maxViews = activeViews.length;
final int viewTypeCount = this.viewTypeCount;
final SparseArray[] scrapViews = this.scrapViews;
for (int i = 0; i < viewTypeCount; ++i) {
final SparseArray scrapPile = scrapViews[i];
int size = scrapPile.size();
final int extras = size - maxViews;
size--;
for (int j = 0; j < extras; j++) {
scrapPile.remove(scrapPile.keyAt(size--));
}
}
}
static View retrieveFromScrap(SparseArray scrapViews, int position) {
int size = scrapViews.size();
if (size > 0) {
// See if we still have a view for this position.
for (int i = 0; i < size; i++) {
int fromPosition = scrapViews.keyAt(i);
View view = scrapViews.get(fromPosition);
if (fromPosition == position) {
scrapViews.remove(fromPosition);
return view;
}
}
int index = size - 1;
View r = scrapViews.valueAt(index);
scrapViews.remove(scrapViews.keyAt(index));
return r;
} else {
return null;
}
}
}
RecyclingPagerAdapter
public abstract class RecyclingPagerAdapter extends PagerAdapter {
static final int IGNORE_ITEM_VIEW_TYPE = AdapterView.ITEM_VIEW_TYPE_IGNORE;
private final RecycleBin recycleBin;
public RecyclingPagerAdapter() {
this(new RecycleBin());
}
RecyclingPagerAdapter(RecycleBin recycleBin) {
this.recycleBin = recycleBin;
recycleBin.setViewTypeCount(getViewTypeCount());
}
@Override public void notifyDataSetChanged() {
recycleBin.scrapActiveViews();
super.notifyDataSetChanged();
}
@Override public final Object instantiateItem(ViewGroup container, int position) {
int viewType = getItemViewType(position);
View view = null;
if (viewType != IGNORE_ITEM_VIEW_TYPE) {
view = recycleBin.getScrapView(position, viewType);
}
view = getView(position, view, container);
container.addView(view);
return view;
}
@Override public final void destroyItem(ViewGroup container, int position, Object object) {
View view = (View) object;
container.removeView(view);
int viewType = getItemViewType(position);
if (viewType != IGNORE_ITEM_VIEW_TYPE) {
recycleBin.addScrapView(view, position, viewType);
}
}
@Override public final boolean isViewFromObject(View view, Object object) {
return view == object;
}
public int getViewTypeCount() {
return 1;
}
@SuppressWarnings("UnusedParameters") // Argument potentially used by subclasses.
public int getItemViewType(int position) {
return 0;
}
public abstract View getView(int position, View convertView, ViewGroup container);
}
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