1.导入Glide依赖
compile 'com.github.bumptech.glide:glide:3.7.0'
2.BannerView类
public class BannerView extends FrameLayout implements ViewPager.OnPageChangeListener {
private boolean isLoop=false;
private ViewPager viewPager;
private BannerAdapter adapter;
private Handler handler;
private LinearLayout points;
private List<ImageView> tips;
private ArrayList<?> dataList; //数据源
private int pointsFocused;
private int pointsUnFocused;
private int defaultPic;
private BannerOnClickListener bannerOnClickListener;
private boolean isPositive = true; //是否正向循环
private Runnable runnable;
public BannerView(Context context) {
super(context);
init(context);
}
public BannerView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
public BannerView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(context);
}
private void init(Context context){
LayoutParams params = new LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
viewPager = new ViewPager(context);
viewPager.setLayoutParams(params);
viewPager.addOnPageChangeListener(this);
addView(viewPager);
handler = new Handler();
points = new LinearLayout(context);
//设置points的LayoutParams
LinearLayout.LayoutParams pLayoutParams = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
points.setLayoutParams(pLayoutParams);
points.setOrientation(LinearLayout.HORIZONTAL);
//这里很重要 设置 layout_gravity 相对于父布局的位置
FrameLayout.LayoutParams layoutParams = new FrameLayout.LayoutParams(points.getLayoutParams());
layoutParams.gravity= (Gravity.BOTTOM|Gravity.CENTER); //设置轮播点靠右下角展示
layoutParams.bottomMargin=dip2px(context,5);
layoutParams.rightMargin=dip2px(context,10);
points.setLayoutParams(layoutParams);
addView(points);
}
/**
* 设置轮播点
* @param number
*/
private void setPoint(int number){
for(int i=0; i<number; i++){
ImageView imageView = new ImageView(getContext());
imageView.setLayoutParams(new ViewGroup.LayoutParams(dip2px(getContext(),10),dip2px(getContext(),10)));
tips.add(imageView);
if(i == 0){
tips.get(i).setBackgroundResource(pointsFocused);
}else{
tips.get(i).setBackgroundResource(pointsUnFocused);
}
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(new ViewGroup.LayoutParams(30,
30));
layoutParams.leftMargin = dip2px(getContext(),2);//轮播点左右间距
layoutParams.rightMargin = dip2px(getContext(),2);//轮播点左右间距
points.addView(imageView, layoutParams);
}
}
/**
* 初始化数据
* @param list 传入的图片数据，本地图片id，网络图片地址都可以
* @param defaultPic 默认的图片，在加载失败或者图片尚未加载完全时显示默认图片
* @param needPoint 是否需要指示点
* @param pointsUnFocused 指示点的未选中状态图片，不需要指示点设为0即可
* @param pointsFocused 指示点的选中状态图片，不需要指示点设为0即可
* @param isLoop 图片是否可以无限循环滑动
*/
public void init(ArrayList<?> list,int defaultPic ,boolean needPoint,int pointsUnFocused,int pointsFocused,boolean isLoop){
if(list==null)return;
dataList =list;
this.defaultPic=defaultPic;//默认图片
this.isLoop=isLoop;//是否轮询
adapter = new BannerAdapter(list);
viewPager.setAdapter(adapter);
//设置指示点
if(list.size()<=1)needPoint=false;//如果只有一张图片就不显示指示点
tips = new ArrayList<>();
if(needPoint){
this.pointsUnFocused=pointsUnFocused;
this.pointsFocused=pointsFocused;
setPoint(list.size());
}
}
/**
* 设置自动循环时间，不设置就不会自动循环
* @param loopTime
*/
public void setAutoLoop(int loopTime){
autoLoop(loopTime);
}
//设置banner点击监听
public void setBannerOnClickListener(BannerOnClickListener bannerOnClickListener){
this.bannerOnClickListener=bannerOnClickListener;
}
//设置banner点击监听
public interface BannerOnClickListener{
void onClick(int position);
}
private void autoLoop(final int time) {
runnable = new Runnable() {
@Override
public void run() {
int item = viewPager.getCurrentItem();
if (item >= adapter.getCount() - 1) {
//判断循环到哪里了
isPositive = false;
} else if (item <= 0) {
isPositive = true;
}
if (isPositive) {
item++;
} else if (!isPositive) {
item--;
}
viewPager.setCurrentItem(item);
handler.postDelayed(this, time);
}
};
handler.postDelayed(runnable,time);
}
/**
* 移除掉handler
*/
public void removeHandler(){
handler.removeCallbacks(runnable);
handler=null;
}
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
position=position%dataList.size();
for(int i=0; i<tips.size(); i++){
if(i == position){
tips.get(i).setBackgroundResource(pointsFocused);
}else{
tips.get(i).setBackgroundResource(pointsUnFocused);
}
}
}
@Override
public void onPageScrollStateChanged(int state) {
}
class BannerAdapter extends PagerAdapter {
private ArrayList<?> list;
public BannerAdapter(ArrayList<?> url) {
list=url;
}
@Override
public int getCount() {
if(!isLoop)return list.size();//不循环
if(list.size()==1){
//循环
return 1;
}else {
return 500*list.size();
}
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view==object;
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
position=position%dataList.size();
ImageView imageView = new ImageView(getContext());
imageView.setBackground(getResources().getDrawable(defaultPic));
imageView.setLayoutParams(new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
//此处用Glide加载图片，如果用的其他的，可以再这里更换
Glide.with(getContext()).load(list.get(position)).error(defaultPic).centerCrop().into(imageView);//Glide加载图片
container.addView(imageView);
final int finalPosition = position;
imageView.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
bannerOnClickListener.onClick(finalPosition);//点击事件的回调
}
});
imageView.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if(event.getAction()==MotionEvent.ACTION_DOWN){
handler.removeCallbacks(runnable); //手指触碰banner条后，停止循环
}
if(event.getAction()==MotionEvent.ACTION_UP){
handler.removeCallbacks(runnable);
handler.postDelayed(runnable,2000); //手指抬起后2秒后继续循环
}
if(event.getAction()==MotionEvent.ACTION_MOVE){
handler.removeCallbacks(runnable);
handler.postDelayed(runnable,2000); //手指抬起后2秒后继续循环
}
return false;
}
});
return imageView;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((View) object);
}
}
private int dip2px(Context context, float dipValue){
final float scale = context.getResources().getDisplayMetrics().density;
return (int)(dipValue * scale + 0.5f);
}
private int px2dip(Context context, float pxValue){
final float scale = context.getResources().getDisplayMetrics().density;
return (int)(pxValue / scale + 0.5f);
}
}
3.Activity
public class MainActivity extends AppCompatActivity {
private BannerView bannerViewView;
private ArrayList<Integer> images = new ArrayList<>(); //设置数据源
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//找到控件
bannerViewView = (BannerView) findViewById(R.id.bannerView);
images.add(R.mipmap.a1);
images.add(R.mipmap.a2);
images.add(R.mipmap.a3);
//设置点击事件监听
bannerViewView.setBannerOnClickListener(new BannerView.BannerOnClickListener() {
@Override
public void onClick(int position) {
}
});
/**
* 初始化数据
* @param list 传入的图片数据，本地图片id，网络图片地址都可以
* @param defaultPic 默认的图片，在加载失败或者图片尚未加载完全时显示默认图片
* @param needPoint 是否需要指示点
* @param pointsUnFocused 指示点的未选中状态图片，不需要指示点设为0即可
* @param pointsFocused 指示点的选中状态图片，不需要指示点设为0即可
* @param isLoop 图片是否可以无限循环滑动
*/
bannerViewView.init(images,R.mipmap.a1,true,R.mipmap.y,R.mipmap.y2,false);
//设置循环播放的间隔时间，不设置就不会循环播放
bannerViewView.setAutoLoop(2000);
}
@Override
protected void onDestroy() {
super.onDestroy();
bannerViewView.removeHandler();//移除掉handler的Callbacks
}
}
4.布局文件xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<com.hnucm18jr.myapplication.BannerView
android:id="@+id/bannerView"
android:layout_width="0dp"
android:layout_height="150dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
运行
