Android用zoom放大缩小图片

用zoom 放大缩小图片 import android.app.Activity; import android.os.Bundle; public class zooming extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle icicle) { super.onCreate(icicle); setContentView(new Zoom(this)); } }

import android.content.Context; import android.graphics.Canvas; import android.graphics.drawable.Drawable; import android.view.KeyEvent; import android.view.View; public class Zoom extends View { private Drawable image; private int zoomControler=20; public Zoom(Context context) { super(context); image=context.getResources().getDrawable(R.drawable.icon); setFocusable(true); } @Override protected void onDraw(Canvas canvas) { // TODO Auto-generated method stub super.onDraw(canvas); //here u can control the width and height of the images........ this line is very important image.setBounds((getWidth()/2)-zoomControler, (getHeight()/2)-zoomControler, (getWidth()/2)+zoomControler, (getHeight()/2)+zoomControler); image.draw(canvas); } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { if(keyCode==KeyEvent.KEYCODE_DPAD_UP)// zoom in zoomControler+=10; if(keyCode==KeyEvent.KEYCODE_DPAD_DOWN) // zoom out zoomControler-=10; if(zoomControler<10) zoomControler=10; invalidate(); return true; } } package com.min.Test_Gallery; import android.app.Activity; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Color; import android.graphics.Matrix; import android.os.Bundle; import android.util.DisplayMetrics; import android.util.Log; import android.view.GestureDetector; import android.view.KeyEvent; import android.view.MotionEvent; import android.view.View; import android.view.GestureDetector.OnGestureListener; import android.view.View.OnTouchListener; import android.widget.Butto...