android 图片的切换实现代码

package com.homer.viewflipper; import android.app.Activity; import android.os.Bundle; import android.view.GestureDetector; import android.view.MotionEvent; import android.view.ViewGroup.LayoutParams; import android.view.animation.Animation; import android.view.animation.AnimationUtils; import android.widget.ImageView; import android.widget.ViewFlipper; public class ViewFlipperActivity extends Activity implements android.view.GestureDetector.OnGestureListener { private int[] imgs = { R.drawable.img1, R.drawable.img2, R.drawable.img3, R.drawable.img4, R.drawable.img5 }; private GestureDetector gestureDetector = null; private ViewFlipper viewFlipper = null; private Activity mActivity = null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mActivity = this; viewFlipper = (ViewFlipper) findViewById(R.id.viewflipper); gestureDetector = new GestureDetector(this); // 声明检测手势事件 for (int i = 0; i < imgs.length; i++) { // 添加图片源 ImageView iv = new ImageView(this); iv.setImageResource(imgs[i]); iv.setScaleType(ImageView.ScaleType.FIT_XY); viewFlipper.addView(iv, new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT)); } viewFlipper.setAutoStart(true); // 设置自动播放功能（点击事件，前自动播放） viewFlipper.setFlipInterval(3000); if(viewFlipper.isAutoStart() && !viewFlipper.isFlipping()){ viewFlipper.startFlipping(); } } @Override public boolean onTouchEvent(MotionEvent event) { viewFlipper.stopFlipping(); // 点击事件后，停止自动播放 viewFlipper.setAutoStart(false); return gestureDetector.onTouchEvent(event); // 注册手势事件 } @Override public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) { if (e2.getX() - e1.getX() > 120) { // 从左向右滑动（左进右出） Animation rInAnim = AnimationUtils.loadAnimation(mActivity, R.anim.push_right_in); // 向右滑动左侧进入的渐变效果（alpha 0.1 -> 1.0） Animation rOutAnim = AnimationUtils.loadAnimation(mActivity, R.anim.push_right_out); // 向右滑动右侧滑出的渐变效果（alpha 1.0 -> 0.1） viewFlipper.setInAnimation(rInAnim); viewFlipper.setOutAnimation(rOutAnim); viewFlipper.showPrevious(); return true; } else if (e2.getX() - e1.getX() < -120) { // 从右向左滑动（右进左出） Animation lInAnim = AnimationUtils.loadAnimation(mActivity, R.anim.push_left_in); // 向左滑动左侧进入的渐变效果（alpha 0.1 -> 1.0） Animation lOutAnim = AnimationUtils.loadAnimation(mActivity, R.anim.push_left_out); // 向左滑动右侧滑出的渐变效果（alpha 1.0 -> 0.1） viewFlipper.setInAnimation(lInAnim); viewFlipper.setOutAnimation(lOutAnim); viewFlipper.showNext(); return true; } return true; } @Override public boolean onDown(MotionEvent e) { return false; } @Override public void onLongPress(MotionEvent e) { } @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { return false; } @Override public void onShowPress(MotionEvent e) { } @Override public boolean onSingleTapUp(MotionEvent e) { return false; } }