<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="@android:color/black"
    >

    <ImageView
        android:layout_width
 
="match_parent"
        android:layout_height="match_parent"
        android:src="@drawable/aefwfaw"
        android:scaleType="matrix"
       android:id="@+id/img" />

</LinearLayout>

activity中

package com.bwi.test;

import android.os.Bundle;
import android.app.Activity;
import android.graphics.Matrix;
 
import android.graphics.PointF;
import android.util.FloatMath;
import android.util.Log;
import android.view.Menu;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.ImageView;

public class MainActivity extends Activity implements
 
 OnTouchListener {

    private Matrix matrix = new Matrix();  
    private Matrix savedMatrix = new Matrix();  

    private static final int NONE = 0;  
    private static final int DRAG = 1;  
    private static final int ZOOM = 2;  
    private int mode = NONE;  

    // 第一個按下的手指的點   
    private PointF startPoint = new PointF();  
    // 兩個按下的手指的觸控點的中點   
    private PointF midPoint = new PointF();  
    // 初始的兩個手指按下的觸控點的距離   
    private float oriDis = 1f;  


    private ImageView img;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        img = (ImageView) findViewById(R.id.img);
        img.setOnTouchListener(this);
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        ImageView view = (ImageView) v;
         // 進行與操作是為了判斷多點觸控   
        switch (event.getAction() & MotionEvent.ACTION_MASK) {  
        case MotionEvent.ACTION_DOWN:  
            // 第一個手指按下事件   
            matrix.set(view.getImageMatrix());  
            savedMatrix.set(matrix);  
            startPoint.set(event.getX(), event.getY());  
            mode = DRAG;  
            break;  
        case MotionEvent.ACTION_POINTER_DOWN:  
            // 第二個手指按下事件   
            oriDis = distance(event);  
            if (oriDis > 10f) {  
                savedMatrix.set(matrix);  
                midPoint = middle(event);  
                mode = ZOOM;  
            }  
            break;  
        case MotionEvent.ACTION_UP:  
        case MotionEvent.ACTION_POINTER_UP:  
            // 手指放開事件   
            mode = NONE;  
            break;  
        case MotionEvent.ACTION_MOVE:  
            // 手指滑動事件   
            if (mode == DRAG) {  
                // 是一個手指拖動   
                matrix.set(savedMatrix);  
                matrix.postTranslate(event.getX() - startPoint.x, event.getY()  
                        - startPoint.y);  
            } else if (mode == ZOOM) {  
                // 兩個手指滑動   
                float newDist = distance(event);  
                if (newDist > 10f) {  
                    matrix.set(savedMatrix);  
                    float scale = newDist / oriDis;  
                    matrix.postScale(scale, scale, midPoint.x, midPoint.y);  
                }  
            }  
            break;  


        }
        // 設定ImageView的Matrix   
        view.setImageMatrix(matrix);  
        return true;  

    }

    private PointF middle(MotionEvent event) {
         float x = event.getX(0) + event.getX(1);  
            float y = event.getY(0) + event.getY(1);  
            return new PointF(x / 2, y / 2);  

    }

    private float distance(MotionEvent event) {
         float x = event.getX(0) - event.getX(1);  
            float y = event.getY(0) - event.getY(1);  
            return FloatMath.sqrt(x * x + y * y);  

    }

    

}