ViewFlipper实现简单手势操作

package com.example.administrator.viewflipper;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ImageView;
import android.widget.ViewFlipper;


public class MainActivity extends ActionBarActivity {
    private ViewFlipper viewFlipper;
    private int[] resId = new int[]{R.drawable.pic1,R.drawable.pic2,R.drawable.pic3,R.drawable.pic4};

    private float startX;
    private enum directions{LEFT,RIGHT,NULL};
    private directions slip_direction;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        viewFlipper = (ViewFlipper)findViewById(R.id.flipper);
        for (int i = 0 ; i < resId.length ; ++i){
            viewFlipper.addView(getImage(resId[i]));
        }

        //自动播放
//        viewFlipper.setInAnimation(this,R.anim.left_in);
//        viewFlipper.setOutAnimation(this, R.anim.left_out);
//        viewFlipper.setFlipInterval(3000);
//        viewFlipper.startFlipping();
    }

    /**
     * 简单的手势操作
     * @param event
     * @return
     */
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        switch (event.getAction()){
            case MotionEvent.ACTION_DOWN:
                startX = event.getX();
                slip_direction = directions.NULL;
                break;
            case MotionEvent.ACTION_MOVE:
                //向右滑
                if(event.getX() - startX > 100){
                    slip_direction = directions.RIGHT;

                }
                //向左滑
                if(startX - event.getX()  > 100){
                    slip_direction = directions.LEFT;
                }
                break;
            case MotionEvent.ACTION_UP:
                switch (slip_direction){
                    case LEFT:
                        if(viewFlipper.isFlipping()){
                            viewFlipper.stopFlipping();
                        }
                        viewFlipper.setInAnimation(this,R.anim.right_in);
                        viewFlipper.setOutAnimation(this, R.anim.right_out);
                        viewFlipper.showPrevious();
                        break;
                    case RIGHT:
                        if(viewFlipper.isFlipping()){
                            viewFlipper.stopFlipping();
                        }
                        viewFlipper.setInAnimation(this, R.anim.left_in);
                        viewFlipper.setOutAnimation(this, R.anim.left_out);
                        viewFlipper.showNext();
                        break;
                    case NULL:
                        break;
                }
                break;
        }
        return super.onTouchEvent(event);
    }

    private ImageView getImage(int resId){
        ImageView img = new ImageView(this);
        img.setImageResource(resId);
        return img;
    }
}