android旋转动画怎么停止工作原理,如何在不使用动画的情况下在android中来回旋转图像...

import android.app.Activity;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.graphics.Matrix;

import android.graphics.drawable.BitmapDrawable;

import android.os.Bundle;

import android.view.MotionEvent;

import android.view.View;

import android.view.animation.AccelerateInterpolator;

import android.view.animation.Animation;

import android.view.animation.AnimationUtils;

import android.widget.Button;

import android.widget.ImageView;

public class dash1 extends Activity {

ImageView img,img1;

Animation an,an1,an2,an3;Button bt,bt2,bt3,bt4;

/** Called when the activity is first created. */

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

img = (ImageView)findViewById(R.id.ImageView01);

final Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.minute);

final int w= bmp.getWidth();

final int h= bmp.getHeight();

final Matrix mat = new Matrix();

mat.postRotate(180);

Bitmap rtd = Bitmap.createBitmap(bmp, 0, 0, w, h, mat, true);

BitmapDrawable bmd = new BitmapDrawable(rtd);

img.setImageDrawable(bmd);

an = AnimationUtils.loadAnimation(this, R.anim.anim);

an1 = AnimationUtils.loadAnimation(this, R.anim.anim1);

an2 = AnimationUtils.loadAnimation(this, R.anim.anim2);

an3 = AnimationUtils.loadAnimation(this, R.anim.anim3);

bt = (Button)findViewById(R.id.Button01);

bt2 = (Button)findViewById(R.id.Button02);

bt3 = (Button)findViewById(R.id.Button03);

bt4 = (Button)findViewById(R.id.Button04);

bt.setOnTouchListener(new View.OnTouchListener() {

@Override

public boolean onTouch(View v, MotionEvent event) {

// TODO Auto-generated method stub

an.setFillAfter(true);

img.startAnimation(an);

return false;

}

});

bt2.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

// TODO Auto-generated method stub

img.startAnimation(an1);

}

});

bt3.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

// TODO Auto-generated method stub

an2.setFillAfter(true);

img.startAnimation(an2);

}

});

bt4.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

// TODO Auto-generated method stub

an3.setFillAfter(true);

img.startAnimation(an3);

}

});

}

}