android手势识别ViewFlipper触摸动画
今天给大家介绍一下如何实现androd主页面的左右拖动效果。实现起来很简单，就是使用ViewFlipper来将您要来回拖动的View装在一起，然 后与GestureDetector手势识别类来联动，确定要显示哪个View，加上一点点动画效果即可。比如当手指向左快速滑动时跳转到上一个 View，手指向右快速滑动时跳转到下一个View，本例中使用图片作为各个View的页面，实现左右快速滑动显示不同的图片。
转自 http://www.ideasandroid.com/archives/414
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layout<linearlayout android:layout_height="fill_parent" android:layout_width="fill_parent" android:orientation="vertical" xmlns:android="http://schemas.android.com/apk/res/android"><viewflipper android:id="@+id/flipper" android:layout_below="@+id/CockpitLayout" android:layout_height="fill_parent" android:layout_width="fill_parent"><include android:id="@+id/firstlayout" layout="@layout/first"></include><include android:id="@+id/secondlayout" layout="@layout/second"></include><include android:id="@+id/thirdlayout" layout="@layout/third"></include><include android:id="@+id/fourthlayout" layout="@layout/fourth"></include> </viewflipper></linearlayout>
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ViewFlipper<linearlayout android:gravity="center_vertical" android:layout_height="fill_parent" android:layout_width="fill_parent" xmlns:android="http://schemas.android.com/apk/res/android"> <imageview android:layout_height="wrap_content" android:layout_width="wrap_content" android:src="@drawable/v1"> </imageview></linearlayout>
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我们的Activity需要实现两个接口OnGestureListener,OnTouchListener。package com.ideasandroid.demo;import android.app.Activity;import android.os.Bundle;import android.view.GestureDetector;import android.view.MotionEvent;import android.view.View;import android.view.GestureDetector.OnGestureListener;import android.view.View.OnTouchListener;import android.view.animation.AccelerateInterpolator;import android.view.animation.Animation;import android.view.animation.TranslateAnimation;import android.widget.ViewFlipper;public class ViewFlipperDemo extends Activity implements OnGestureListener,OnTouchListener{private ViewFlipper mFlipper;GestureDetector mGestureDetector;private int mCurrentLayoutState;private static final int FLING_MIN_DISTANCE = 100;private static final int FLING_MIN_VELOCITY = 200;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);mFlipper = (ViewFlipper) findViewById(R.id.flipper);//注册一个用于手势识别的类mGestureDetector = new GestureDetector(this);//给mFlipper设置一个listenermFlipper.setOnTouchListener(this);mCurrentLayoutState = 0;//允许长按住ViewFlipper,这样才能识别拖动等手势mFlipper.setLongClickable(true);}/** * 此方法在本例中未用到，可以指定跳转到某个页面 * @param switchTo */public void switchLayoutStateTo(int switchTo) {while (mCurrentLayoutState != switchTo) {if (mCurrentLayoutState > switchTo) {mCurrentLayoutState--;mFlipper.setInAnimation(inFromLeftAnimation());mFlipper.setOutAnimation(outToRightAnimation());mFlipper.showPrevious();} else {mCurrentLayoutState++;mFlipper.setInAnimation(inFromRightAnimation());mFlipper.setOutAnimation(outToLeftAnimation());mFlipper.showNext();}};}/** * 定义从右侧进入的动画效果 * @return */protected Animation inFromRightAnimation() {Animation inFromRight = new TranslateAnimation(Animation.RELATIVE_TO_PARENT, +1.0f,Animation.RELATIVE_TO_PARENT, 0.0f,Animation.RELATIVE_TO_PARENT, 0.0f,Animation.RELATIVE_TO_PARENT, 0.0f);inFromRight.setDuration(500);inFromRight.setInterpolator(new AccelerateInterpolator());return inFromRight;}/** * 定义从左侧退出的动画效果 * @return */protected Animation outToLeftAnimation() {Animation outtoLeft = new TranslateAnimation(Animation.RELATIVE_TO_PARENT, 0.0f,Animation.RELATIVE_TO_PARENT, -1.0f,Animation.RELATIVE_TO_PARENT, 0.0f,Animation.RELATIVE_TO_PARENT, 0.0f);outtoLeft.setDuration(500);outtoLeft.setInterpolator(new AccelerateInterpolator());return outtoLeft;}/** * 定义从左侧进入的动画效果 * @return */protected Animation inFromLeftAnimation() {Animation inFromLeft = new TranslateAnimation(Animation.RELATIVE_TO_PARENT, -1.0f,Animation.RELATIVE_TO_PARENT, 0.0f,Animation.RELATIVE_TO_PARENT, 0.0f,Animation.RELATIVE_TO_PARENT, 0.0f);inFromLeft.setDuration(500);inFromLeft.setInterpolator(new AccelerateInterpolator());return inFromLeft;}/** * 定义从右侧退出时的动画效果 * @return */protected Animation outToRightAnimation() {Animation outtoRight = new TranslateAnimation(Animation.RELATIVE_TO_PARENT, 0.0f,Animation.RELATIVE_TO_PARENT, +1.0f,Animation.RELATIVE_TO_PARENT, 0.0f,Animation.RELATIVE_TO_PARENT, 0.0f);outtoRight.setDuration(500);outtoRight.setInterpolator(new AccelerateInterpolator());return outtoRight;}public boolean onDown(MotionEvent e) {// TODO Auto-generated method stubreturn false;}/* * 用户按下触摸屏、快速移动后松开即触发这个事件 * e1：第1个ACTION_DOWN MotionEvent * e2：最后一个ACTION_MOVE MotionEvent * velocityX：X轴上的移动速度，像素/秒 * velocityY：Y轴上的移动速度，像素/秒 * 触发条件 ： * X轴的坐标位移大于FLING_MIN_DISTANCE，且移动速度大于FLING_MIN_VELOCITY个像素/秒 */public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,float velocityY) {if (e1.getX() - e2.getX() > FLING_MIN_DISTANCE && Math.abs(velocityX) > FLING_MIN_VELOCITY) { // 当像左侧滑动的时候//设置View进入屏幕时候使用的动画mFlipper.setInAnimation(inFromRightAnimation());//设置View退出屏幕时候使用的动画mFlipper.setOutAnimation(outToLeftAnimation());mFlipper.showNext(); } else if (e2.getX() - e1.getX() > FLING_MIN_DISTANCE && Math.abs(velocityX) > FLING_MIN_VELOCITY) { // 当像右侧滑动的时候mFlipper.setInAnimation(inFromLeftAnimation());mFlipper.setOutAnimation(outToRightAnimation());mFlipper.showPrevious(); }return false;}public void onLongPress(MotionEvent e) {// TODO Auto-generated method stub}public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,float distanceY) {return false;}public void onShowPress(MotionEvent e) {// TODO Auto-generated method stub}public boolean onSingleTapUp(MotionEvent e) {// TODO Auto-generated method stubreturn false;}public boolean onTouch(View v, MotionEvent event) {// 一定要将触屏事件交给手势识别类去处理（自己处理会很麻烦的）return mGestureDetector.onTouchEvent(event);}}??
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