[转][Android]滑动银屏效果GestureDetector、OnGestureListener、ViewFlipper
[转][Android]滑动屏幕效果GestureDetector、OnGestureListener、ViewFlipper原文：http://blog.csdn.net/fen
[转][Android]滑动屏幕效果GestureDetector、OnGestureListener、ViewFlipper
原文：http://blog.csdn.net/feng88724/article/details/6170694
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屏幕切换指的是在同一个Activity内屏幕见的切换。
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通过GestureDetector、OnGestureListener实现滑屏事件。ViewFlipper是继承至FrameLayout的，所以它是一个Layout里面可以放置多个View。示例中第一页仅放了一个按钮BUTTON，向下滑屏时，每页都只放了一个TEXTVIEW。
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页面：
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<?xml?version="1.0"?encoding="utf-8"?>??<LinearLayout?xmlns:android="http://schemas.android.com/apk/res/android"??????android:orientation="vertical"??????android:layout_width="fill_parent"??????android:layout_height="fill_parent"??????>??????<ViewFlipper?android:id="@+id/ViewFlipper01"??????????android:layout_width="fill_parent"?android:layout_height="fill_parent">??????</ViewFlipper>??</LinearLayout>????
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Activity代码:
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package?com.yfz;??import?android.app.Activity;??import?android.os.Bundle;??import?android.util.Log;??import?android.view.GestureDetector;??import?android.view.MotionEvent;??import?android.view.View;??import?android.view.GestureDetector.OnGestureListener;??import?android.view.ViewGroup.LayoutParams;??import?android.view.animation.AnimationUtils;??import?android.widget.Button;??import?android.widget.ExpandableListView;??import?android.widget.TextView;??import?android.widget.ViewFlipper;??public?class?Flip?extends?Activity?implements?OnGestureListener?{????????????private?GestureDetector?detector;??????private?ViewFlipper?flipper;????????????/**?Called?when?the?activity?is?first?created.?*/??????@Override??????public?void?onCreate(Bundle?savedInstanceState)?{??????????super.onCreate(savedInstanceState);??????????setContentView(R.layout.main);????????????????????flipper?=?(ViewFlipper)?this.findViewById(R.id.ViewFlipper01);????????????????????flipper.addView(addButtonByText("按钮"),new?LayoutParams(LayoutParams.FILL_PARENT,?LayoutParams.WRAP_CONTENT));????????????????????detector?=?new?GestureDetector(this);??????}????????????public?View?addButtonByText(String?text){??????????Button?btn?=?new?Button(this);????????????btn.setText(text);????????????return?btn;????????}????????public?View?addTextByText(String?text){??????????TextView?tv?=?new?TextView(this);????????????tv.setText(text);????????????tv.setGravity(1);????????????return?tv;????????}??????????????@Override??????public?boolean?onTouchEvent(MotionEvent?event)?{??????????Log.i("Fling",?"Activity?onTouchEvent!");??????????return?this.detector.onTouchEvent(event);??????}??????@Override??????public?boolean?onDown(MotionEvent?e)?{??????????//?TODO?Auto-generated?method?stub??????????return?false;??????}????????????/**??????*?监听滑动??????*/??????@Override??????public?boolean?onFling(MotionEvent?e1,?MotionEvent?e2,?float?velocityX,??????????????float?velocityY)?{??????????//?TODO?Auto-generated?method?stub??????????Log.i("Fling",?"Fling?Happened!");??????????if?(e1.getX()?-?e2.getX()?>?120)?{??????????????this.flipper.setInAnimation(AnimationUtils.loadAnimation(this,R.anim.push_left_in));??????????????this.flipper.setOutAnimation(AnimationUtils.loadAnimation(this,R.anim.push_left_out));??????????????this.flipper.addView(addTextByText("文本框"),new?LayoutParams(LayoutParams.FILL_PARENT,?LayoutParams.WRAP_CONTENT));??????????????this.flipper.showNext();??????????????return?true;??????????}?else?if?(e1.getX()?-?e2.getX()?<?-120)?{??????????????this.flipper.setInAnimation(AnimationUtils.loadAnimation(this,R.anim.push_right_in));??????????????this.flipper.setOutAnimation(AnimationUtils.loadAnimation(this,R.anim.push_right_out));??????????????this.flipper.showPrevious();??????????????return?true;??????????}??????????return?true;??????}??????@Override??????public?void?onLongPress(MotionEvent?e)?{??????????//?TODO?Auto-generated?method?stub????????????????}??????@Override??????public?boolean?onScroll(MotionEvent?e1,?MotionEvent?e2,?float?distanceX,??????????????float?distanceY)?{??????????//?TODO?Auto-generated?method?stub??????????return?false;??????}??????@Override??????public?void?onShowPress(MotionEvent?e)?{??????????//?TODO?Auto-generated?method?stub????????????????}??????@Override??????public?boolean?onSingleTapUp(MotionEvent?e)?{??????????//?TODO?Auto-generated?method?stub??????????return?false;??????}??}????
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这里实现的功能是从右往左滑动则切换到上一个View，从左往右滑动则切换到下一个View，并且使用不同的in、out 动画使切换效果看起来统一一些。
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滑屏实现：
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通过android.view.GestureDetector类可以检测各种手势事件，该类有两个回调接口分别用来通知具体的事件：?GestureDetector.OnDoubleTapListener：用来通知DoubleTap事件，类似于鼠标的双击事件，该接口有如下三个回调函数：?1.???onDoubleTap(MotionEvent e)：通知DoubleTap手势，2.???onDoubleTapEvent(MotionEvent e)：通知DoubleTap手势中的事件，包含down、up和move事件（这里指的是在双击之间发生的事件，例如在同一个地方双击会产生DoubleTap手势，而在DoubleTap手势里面还会发生down和up事件，这两个事件由该函数通知）；3.???onSingleTapConfirmed(MotionEvent e)：用来判定该次点击是SingleTap而不是DoubleTap，如果连续点击两次就是DoubleTap手势，如果只点击一次，系统等待一段时间后没有收到第二次点击则判定该次点击为SingleTap而不是DoubleTap，然后触发SingleTapConfirmed事件。GestureDetector.OnGestureListener：用来通知普通的手势事件，该接口有如下六个回调函数：1.???onDown(MotionEvent e)：down事件；2.???onSingleTapUp(MotionEvent e)：一次点击up事件；3.???onShowPress(MotionEvent e)：down事件发生而move或则up还没发生前触发该事件；4.???onLongPress(MotionEvent e)：长按事件；5.???onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY)：滑动手势事件；6.???onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY)：在屏幕上拖动事件。本次仅用到了OnGestureListener类中的onFling方法。 ?其他手势事件各位可以自己回去试验。简单说明：要实现屏幕切换的话，首先需要定义一个GestureDetector：private?GestureDetector mGestureDetector;?并在onCreate函数中初始化：mGestureDetector =?new?GestureDetector(this);?同时Activity要继承OnGestureListener接口，并实现其中的onFling方法。另外Activity的onTouchEvent事件也要实现！！另外本例View切换时还有动画效果。使用Animation类实现，相关的函数：?- setInAnimation：设置View进入屏幕时候使用的动画，该函数有两个版本:一个接受单个参数，类型为android.view.animation.Animation；一个接受两个参数，类型为Context和int，分别为Context对象和定义Animation的resourceID。
