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

packagecom.yuanlp.testp_w_picpath;importandroid.graphics.Bitmap;importandroid.graphics.BitmapFactory;importandroid.graphics.Canvas;importandroid.graphics.Color;importandroid.graphics.Matrix;importandroid.graphics.Paint;importandroid.os.Bundle;importandroid.support.v7.app.AppCompatActivity;importandroid.view.View;importandroid.widget.ImageView;publicclassMainActivityextendsAppCompatActivity{privateImageViewiv;@OverrideprotectedvoidonCreate(BundlesavedInstanceState){super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);iv=(ImageView)findViewById(R.id.iv);}publicvoidturnBig(Viewview){Bitmapbitmap=BitmapFactory.decodeResource(getResources(),R.drawable.meinv);Matrixmatrix=newMatrix();matrix.setScale(2,2);//放大四倍，水平方向2倍，竖直方向2倍//买一张纸Bitmapbitmap1=Bitmap.createBitmap(bitmap.getWidth()*2,bitmap.getHeight()*2,bitmap.getConfig());//买个画板Canvascanvas=newCanvas(bitmap1);//临摹会话Paintpaint=newPaint();paint.setColor(Color.BLACK);canvas.drawBitmap(bitmap,matrix,paint);//传入新纸iv.setImageBitmap(bitmap1);}publicvoidturnSmall(Viewview){Bitmapbitmap=BitmapFactory.decodeResource(getResources(),R.drawable.meinv);Matrixmatrix=newMatrix();matrix.setScale(0.5f,0.5f);//买个纸Bitmapbitmap1=Bitmap.createBitmap(bitmap.getWidth()/2,bitmap.getHeight()/2,bitmap.getConfig());//买个画板Canvascanvas=newCanvas(bitmap1);Paintpaint=newPaint();paint.setColor(Color.BLACK);canvas.drawBitmap(bitmap,matrix,paint);iv.setImageBitmap(bitmap1);}}