package example.com.myapplication;import android.app.Activity;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Matrix;import android.os.Bundle;import android.util.DisplayMetrics;import android.view.View;import android.view.View.OnClickListener;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.ZoomControls;public class MainActivity extends Activity {  private LinearLayout llLayout;  private ZoomControls zoomcontrols;  private ImageView img;  private int id=0;  private int displayWidth;  private int displayHeight;  private float scaleWidth = 1;  private float scaleHeight = 1;  private Bitmap bitmap;  @Override  public void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    llLayout =(LinearLayout)findViewById(R.id.layout);    //取得屏幕分辨率大小    DisplayMetrics dm = new DisplayMetrics();    getWindowManager().getDefaultDisplay().getMetrics(dm);    displayWidth = dm.widthPixels;    //屏幕高度減去zoomControls的高度    displayHeight = dm.heightPixels;    bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.c);    img =(ImageView)findViewById(R.id.image);    //zoom.hide();隱藏zoomControls    //zoom.show();顯示zoomCOntrols    zoomcontrols =(ZoomControls)findViewById(R.id.zoomcontrol);    img =(ImageView)findViewById(R.id.image);    zoomcontrols.setIsZoomInEnabled(true);    zoomcontrols.setIsZoomOutEnabled(true);    //圖片放大    zoomcontrols.setOnZoomInClickListener(new OnClickListener()    {      public void onClick(View v)      {        int bmpWidth = bitmap.getWidth();        int bmpHeight = bitmap.getHeight();        //設置圖片放大但比例        double scale = 1.25;        //計算這次要放大的比例        scaleWidth =(float)(scaleWidth*scale);        scaleHeight =(float)(scaleHeight*scale);        //產生新的大小但Bitmap對象        Matrix matrix = new Matrix();        matrix.postScale(scaleWidth, scaleHeight);        Bitmap resizeBmp = Bitmap.createBitmap(bitmap,0,0,bmpWidth,bmpHeight,matrix,true);        img.setImageBitmap(resizeBmp);      }    });    //圖片減小    zoomcontrols.setOnZoomOutClickListener(new OnClickListener()    {      public void onClick(View v) {        int bmpWidth = bitmap.getWidth();        int bmpHeight = bitmap.getHeight();        //設置圖片放大但比例        double scale = 0.8;        //計算這次要放大的比例        scaleWidth =(float)(scaleWidth*scale);        scaleHeight =(float)(scaleHeight*scale);        //產生新的大小但Bitmap對象        Matrix matrix = new Matrix();        matrix.postScale(scaleWidth, scaleHeight);        Bitmap resizeBmp = Bitmap.createBitmap(bitmap,0,0,bmpWidth,bmpHeight,matrix,true);        img.setImageBitmap(resizeBmp);      }    });  }}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  android:orientation="vertical"  android:layout_width="fill_parent"  android:layout_height="fill_parent"  android:id="@+id/layout"  >  <ImageView    android:id="@+id/image"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:src="@drawable/c"    />  <ZoomControls    android:id="@+id/zoomcontrol"    android:layout_gravity="bottom"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    />  </LinearLayout>