Android实现轮播图片效果

本文实例为大家分享了Android实现轮播图片效果的具体代码，供大家参考，具体内容如下

首先，将这些要轮播的图片和一些文本分别放置在不同的数据集合中，程序启动的时候默认显示一组图片和文本数据，然后启动一个定时器，每隔一段时间便替换掉显示的图片和文本数据，同时加入一些动画效果，已达到轮播的特效。同时，我们也要实现手指滑动图片达到轮播的效果。

1、程序启动界面MainActivity

public class MainActivity extends AppCompatActivity implements ImageBannerFramLayout.FramLayoutLisenner{  private ImageBannerFramLayout mGroup;  private int[] ids = new int[] { R.drawable.i1,//图片资源1 R.drawable.i2,//图片资源2  };  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    //计算当前手机宽度    DisplayMetrics displayMetrics = new DisplayMetrics();    getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);    int width = displayMetrics.widthPixels;    mGroup = (ImageBannerFramLayout) findViewById(R.id.image_group);    mGroup.setLisenner(this);    List list = new ArrayList<>();    for (int i = 0; i < ids.length; i++) { Bitmap bitmap = BitmapFactory.decodeResource(getResources(),ids[i]); list.add(bitmap);    }    mGroup.addBitmaps(list);  }   @Override  public void chickImageIndex(int pos) {    Toast.makeText(this,"索引值 = " + pos,Toast.LENGTH_SHORT).show();  }}

2、新建包view下面新建两个类

1）新建ImageBarnnerViewGroup类继承自ViewGroup

public class ImageBarnnerViewGroup extends ViewGroup {  private int children;//我们View Group的子视图总个数  private int childwidth;//子视图的宽度  private int childheight;//子视图的高度   private int x;//此时的x的值代表的是第一次按下的位置的横坐标，每一次移动过的过程中 移动之前的位置横坐标  private int index = 0;//代表名为每张图片的索引  private Scroller scroller;     private boolean isClick;//true的时候点击事件，false的时候不是点击事件  private ImageBarnnerLister lister;   private ImageBarnnerViewGroupLisnner barnnerViewGroupLisnner;   public ImageBarnnerLister getLister() {    return lister;  }   public void setLister(ImageBarnnerLister lister) {    this.lister = lister;  }   public ImageBarnnerViewGroupLisnner getBarnnerViewGroupLisnner() {    return barnnerViewGroupLisnner;  }  public void setBarnnerViewGroupLisnner(ImageBarnnerViewGroupLisnner barnnerViewGroupLisnner) {    this.barnnerViewGroupLisnner = barnnerViewGroupLisnner;  }  public interface ImageBarnnerLister {    void chickImageIndex(int pos);//pos代表的是我们当前的图片的具体索引值  }      //自动轮播  private boolean isAuto = true;//默认情况下开启轮播  private Timer timer = new Timer();  private TimerTask timerTask;    @SuppressLint("HandlerLeak")  private android.os.Handler autohandler = new android.os.Handler() {    @Override    public void handleMessage(Message msg) { switch (msg.what) { case 0://我们需要图片的自动轮播   if (++index >= children) {//如果是最后一张图片，从第一张开始index = 0;   }   scrollTo(childwidth * index,0);   barnnerViewGroupLisnner.selectImage(index);   break; default: }    }  };   private void startAuto() {    isAuto = true;   }   private void stopAuto() {    isAuto = false;  }      public ImageBarnnerViewGroup(Context context) {    super(context);    initObj();  }   public ImageBarnnerViewGroup(Context context, AttributeSet attrs) {    super(context, attrs);    initObj();  }   public ImageBarnnerViewGroup(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {    super(context, attrs, defStyleAttr, defStyleRes);    initObj();  }    private void initObj() {    scroller = new Scroller(getContext());     timerTask = new TimerTask() { @Override public void run() { if (isAuto) {//开启轮播图   autohandler.sendEmptyMessage(0); } }    };    timer.schedule(timerTask,100,3000);  }   @Override  public void computeScroll() {    super.computeScroll();    if (scroller.computeScrollOffset()) { scrollTo(scroller.getCurrX(),0); invalidate();//重绘    }  }   @Override  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {    super.onMeasure(widthMeasureSpec, heightMeasureSpec);    //1.求出子视图的个数    children = getChildCount();//我们可以知道自试图的个数    if (0 == children)    { setMeasuredDimension(0,0);    } else { measureChildren(widthMeasureSpec, heightMeasureSpec); //此时我们以第一个子视图=为基准，也就是说我们的View Group View view = getChildAt(0); childwidth = view.getMeasuredWidth(); childheight = view.getMeasuredHeight(); int width = view.getMeasuredWidth() * children; setMeasuredDimension(width,childheight);    }    //2.测量子视图的宽度和高度    //3.根据子视图的狂赌和高度，求出该ViewGroup的宽度和高度  }   @Override  public boolean onInterceptTouchEvent(MotionEvent ev) {    return super.onInterceptTouchEvent(ev);  }     @Override  public boolean onTouchEvent(MotionEvent event) {    switch (event.getAction()) { case MotionEvent.ACTION_DOWN://表示用户按下的一瞬间 stopAuto();//停止图片轮播 if (!scroller.isFinished()) {   scroller.abortAnimation(); } isClick = true; x=(int)event.getX(); break; case MotionEvent.ACTION_MOVE://表示用户按下之后在屏幕上移动的过程 int moveX = (int) event.getX(); int distance = moveX - x; scrollBy(-distance,0); x = moveX; isClick = false; break; case MotionEvent.ACTION_UP://标识的是用户抬起的一瞬间 int scrollX = getScrollX(); index = (scrollX + childwidth / 2) / childwidth; if (index < 0) {  //已经滑动到了最左边   index = 0; } else if (index > children - 1) {//说明已经滑动到了最右边   index = children - 1; }  if (isClick) { //点击事件   lister.chickImageIndex(index); } else {   int dx = index * childwidth - scrollX;   scroller.startScroll(scrollX,0,dx,0);   postInvalidate();   barnnerViewGroupLisnner.selectImage(index); } startAuto();//开启图片轮播 break; default:    }    return true;    //返回true的目的是告诉该View Group容器的父View 我们已经处理好了该事件  }   @Override  protected void onLayout(boolean b, int i, int i1, int i2, int i3) {    if (b) { int lefrMargin = 0; for (int j = 0; j < children; j++) { View view = getChildAt(j); view.layout(lefrMargin,0,lefrMargin + childwidth,childheight); lefrMargin += childwidth; }    }  }   public interface ImageBarnnerViewGroupLisnner{    void selectImage(int index);  }}

2）新建ImageBannerFramLayout类继承自frameLayout实现两个接口

public class ImageBannerFramLayout extends frameLayout implements ImageBarnnerViewGroup.ImageBarnnerViewGroupLisnner,ImageBarnnerViewGroup.ImageBarnnerLister{   private ImageBarnnerViewGroup imageBarnnerViewGroup;  private LinearLayout linearLayout;   private FramLayoutLisenner lisenner;   public FramLayoutLisenner getLisenner() {    return lisenner;  }   public void setLisenner(FramLayoutLisenner lisenner) {    this.lisenner = lisenner;  }   public ImageBannerFramLayout(@NonNull Context context) {    super(context);    initImageBarnnerViewGroup();    initDotLinearlayout();  }     public ImageBannerFramLayout(@NonNull Context context, @Nullable AttributeSet attrs) {    super(context, attrs);    initImageBarnnerViewGroup();    initDotLinearlayout();  }   public ImageBannerFramLayout(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {    super(context, attrs, defStyleAttr);    initImageBarnnerViewGroup();    initDotLinearlayout();  }   public void addBitmaps(List list) {    for (int i = 0; i < list.size(); i++) { Bitmap bitmap = list.get(i); addBitmapToImageBarnnerViewGroup(bitmap); addDotToLinearlayout();    }  }   private void addDotToLinearlayout() {    ImageView iv = new ImageView(getContext());    LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams (LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.MATCH_PARENT);    layoutParams.setMargins(5,5,5,5);    iv.setLayoutParams(layoutParams);    iv.setImageResource(R.drawable.dot_normal);    linearLayout.addView(iv);  }   private void addBitmapToImageBarnnerViewGroup(Bitmap bitmap) {    ImageView imageView = new ImageView(getContext());    imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);    imageView.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,ViewGroup.LayoutParams.WRAP_CONTENT));    imageView.setImageBitmap(bitmap);    imageBarnnerViewGroup.addView(imageView);  }   //初始化自定义图片轮播功能核心类  private void initImageBarnnerViewGroup() {    imageBarnnerViewGroup = new ImageBarnnerViewGroup(getContext());    frameLayout.LayoutParams layoutParams = new frameLayout.LayoutParams (frameLayout.LayoutParams.MATCH_PARENT, frameLayout.LayoutParams.MATCH_PARENT);    imageBarnnerViewGroup.setLayoutParams(layoutParams);    imageBarnnerViewGroup.setBarnnerViewGroupLisnner(this);//将linsnner传递给Framlayout    imageBarnnerViewGroup.setLister(this);    addView(imageBarnnerViewGroup);  }   //初始化底部圆点布局  private void initDotLinearlayout() {    linearLayout = new LinearLayout(getContext());    frameLayout.LayoutParams layoutParams = new frameLayout.LayoutParams (frameLayout.LayoutParams.MATCH_PARENT, 40);    linearLayout.setLayoutParams(layoutParams);    linearLayout.setOrientation(LinearLayout.HORIZONTAL);    linearLayout.setGravity(Gravity.CENTER);     linearLayout.setBackgroundColor(Color.RED);    addView(linearLayout);     frameLayout.LayoutParams layoutParams1 = (LayoutParams) linearLayout.getLayoutParams();    layoutParams.gravity = Gravity.BOTTOM;    linearLayout.setLayoutParams(layoutParams1);    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) { linearLayout.setAlpha(0.5f);    } else { linearLayout.getBackground().setAlpha(100);    }  }    @Override  public void selectImage(int index) {    int count = linearLayout.getChildCount();    for (int i = 0;i < count; i++) { ImageView iv = (ImageView) linearLayout.getChildAt(i); if (i == index) { iv.setImageResource(R.drawable.dot_select); } else { iv.setImageResource(R.drawable.dot_normal); }    }  }   @Override  public void chickImageIndex(int pos) {    lisenner.chickImageIndex(pos);  }   public interface FramLayoutLisenner{    void chickImageIndex(int pos);  }}

3、程序布局页面activity_main

ntext=".MainActivity">    

4、新建两个drawable资源文件dot_normal.xml和dot_select.xml，实现轮播图底部小圆点

不同的是前者颜色为白色后者为黑色

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持好好学习网。