Android图像变化

暂时不需要研究具体详细的怎么实现过程，直接使用已有的方法即可，代码如下

package com.yuanlp.testp_w_picpath;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Matrix;import android.graphics.Paint;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.view.View;import android.widget.ImageView;public class MainActivity extends AppCompatActivity {    private ImageView iv;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        iv = (ImageView) findViewById(R.id.iv);    }    public void turnBig(View view){        Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.meinv);        Matrix matrix=new Matrix();        matrix.setScale(2,2);  //放大四倍，水平方向2倍，竖直方向2倍        //买一张纸        Bitmap bitmap1 = Bitmap.createBitmap(bitmap.getWidth() * 2, bitmap.getHeight() * 2, bitmap.getConfig());        //买个画板        Canvas canvas = new Canvas(bitmap1);        //临摹会话        Paint paint = new Paint();        paint.setColor(Color.BLACK);        canvas.drawBitmap(bitmap,matrix,paint);        //传入新纸        iv.setImageBitmap(bitmap1);    }    public void turnSmall(View view){        Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.meinv);        Matrix matrix=new Matrix();        matrix.setScale(0.5f,0.5f);        //买个纸        Bitmap bitmap1 = Bitmap.createBitmap(bitmap.getWidth() / 2, bitmap.getHeight() / 2, bitmap.getConfig());        //买个画板        Canvas canvas=new Canvas(bitmap1);        Paint paint=new Paint();        paint.setColor(Color.BLACK);        canvas.drawBitmap(bitmap,matrix,paint);        iv.setImageBitmap(bitmap1);    }}