Android左右滑动实现Activity切换类 (整合代码实例)

先上图吧，下图是左右拖动的过程：

具体代码如下：Fling_Gallery类
[java]
package com.xu81.testflip;
import android.content.Context;
import android.view.GestureDetector;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.view.animation.Interpolator;
import android.view.animation.Transformation;
import android.widget.Adapter;
import android.widget.FrameLayout;
import android.widget.LinearLayout;

// TODO:

// 1. In order to improve performance Cache screen bitmap and use for animation
// 2. Establish superfluous memory allocations and delay or replace with reused objects
//    Probably need to make sure we are not allocating objects (strings, etc.) in loops

public class FlingGallery extends FrameLayout
{
    // Constants

    private final int swipe_min_distance = 120;
    private final int swipe_max_off_path = 250;
    private final int swipe_threshold_veloicty = 400;

    // Properties

    private int mViewPaddingWidth = 0;
    private int mAnimationDuration = 250;
    private float mSnapBorderRatio = 0.5f;
    private boolean mIsGalleryCircular = true;

    // Members

    private int mGalleryWidth = 0;
    private boolean mIsTouched = false;
    private boolean mIsDragging = false;
    private float mCurrentOffset = 0.0f;
    private long mScrollTimestamp = 0;
    private int mFlingDirection = 0;
    private int mCurrentPosition = 0;
    private int mCurrentViewNumber = 0;

    private Context mContext;
    private Adapter mAdapter;
    private FlingGalleryView[] mViews;
    private FlingGalleryAnimation mAnimation;
    private GestureDetector mGestureDetector;
    private Interpolator mDecelerateInterpolater;

    public FlingGallery(Context context)
    {
        super(context);

        mContext = context;
        mAdapter = null;

        mViews = new FlingGalleryView[3];
        mViews[0] = new FlingGalleryView(0, this);
        mViews[1] = new FlingGalleryView(1, this);
        mViews[2] = new FlingGalleryView(2, this);

        mAnimation = new FlingGalleryAnimation();
        mGestureDetector = new GestureDetector(new FlingGestureDetector());
        mDecelerateInterpolater = AnimationUtils.loadInterpolator(mContext, android.R.anim.decelerate_interpolator);
    }

    public void setPaddingWidth(int viewPaddingWidth)
    {
        mViewPaddingWidth = viewPaddingWidth;
    }

    public void setAnimationDuration(int animationDuration)
    {
        mAnimationDuration = animationDuration;
    }

    public void setSnapBorderRatio(float snapBorderRatio)
    {
        mSnapBorderRatio = snapBorderRatio;
    }

    public void setIsGalleryCircular(boolean isGalleryCircular)
    {
        if (mIsGalleryCircular != isGalleryCircular)
        {
            mIsGalleryCircular = isGalleryCircular;

            if (mCurrentPosition == getFirstPosition())
            {
                // We need to reload the view immediately to the left to change it to circular view or blank
                mViews[getPrevViewNumber(mCurrentViewNumber)].recycleView(getPrevPosition(mCurrentPosition));
            }

            if (mCurrentPosition == getLastPosition())
            {
                // We need to reload the view immediately to the right to change it to circular view or blank
                mViews[getNextViewNumber(mCurrentViewNumber)].recycleView(getNextPosition(mCurrentPosition));
            }
        }
    }

    public int getGalleryCount()
    {
        return (mAdapter == null) ? 0 : mAdapter.getCount();
    }

    public int getFirstPosition()
    {
        return 0;
    }

    public int getLastPosition()
    {
        return (getGalleryCount() == 0) ? 0 : getGalleryCount() - 1;
    }

    private int getPrevPosition(int relativePosition)
    {
    &n

补充：移动开发 , Android ,