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);
}
}
