图片简单放大
先上效果图：
[img]
[/img]
布局文件：
main.xm
<?xml version="1.0" encoding="utf-8"?><FrameLayoutxmlns:android="http://schemas.android.com/apk/res/android"android:orientation="vertical"android:layout_width="fill_parent"android:layout_height="fill_parent"android:id="@+id/layout1"><RelativeLayoutxmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="fill_parent"android:layout_height="fill_parent"android:id="@+id/rl"><ScrollViewxmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="fill_parent"android:layout_height="fill_parent"android:layout_weight="19"android:scrollbars="none"android:fadingEdge="vertical"android:layout_gravity="center"android:gravity="center"><HorizontalScrollViewandroid:layout_height="fill_parent"android:layout_width="fill_parent"android:scrollbars="none"android:layout_gravity="center"android:gravity="center"android:id="@+id/hs"><LinearLayoutandroid:orientation="horizontal"android:layout_width="fill_parent"android:layout_height="fill_parent"android:id="@+id/layoutImage"android:layout_gravity="center"android:gravity="center"><ImageViewandroid:layout_gravity="center"android:gravity="center"android:id="@+id/myImageView"android:layout_width="fill_parent"android:layout_height="fill_parent"android:layout_weight="19"android:paddingTop="5dip"android:paddingBottom="5dip" /></LinearLayout></HorizontalScrollView></ScrollView><ZoomControlsandroid:id="@+id/zoomcontrol"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_centerHorizontal="true"android:layout_alignParentBottom="true" /></RelativeLayout></FrameLayout>
package com.magus.img;import android.app.Activity;import android.app.Dialog;import android.app.ProgressDialog;import android.content.DialogInterface;import android.content.DialogInterface.OnKeyListener;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Matrix;import android.os.Bundle;import android.os.Handler;import android.util.DisplayMetrics;import android.util.Log;import android.view.KeyEvent;import android.view.MotionEvent;import android.view.View;import android.view.View.OnClickListener;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.RelativeLayout;import android.widget.ZoomControls;public class MainActivity extends Activity { /** Called when the activity is first created. */private final int LOADING_IMAGE = 1;public static String KEY_IMAGEURI = "ImageUri";private ZoomControls zoom;private ImageView mImageView;private LinearLayout layoutImage;private int displayWidth;private int displayHeight;/**图片资源*/private Bitmap bmp;/**宽的缩放比例*/private float scaleWidth = 1;/**高的缩放比例*/private float scaleHeight = 1;/**用来计数放大+1 缩小-1*/private int zoomNumber=0;/**点击屏幕显示缩放按钮，三秒消失*/private int showTime=3000;RelativeLayout rl;Handler mHandler = new Handler();private Runnable task = new Runnable() {public void run() {zoom.setVisibility(View.INVISIBLE);}}; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main);//showDialog(LOADING_IMAGE);//图片是从网络上获取的话，需要加入滚动条 bmp=BitmapFactory.decodeResource(getResources(), R.drawable.image);//removeDialog(LOADING_IMAGE); initZoom();} @Overrideprotected Dialog onCreateDialog(int id) {switch (id) {case LOADING_IMAGE: {final ProgressDialog dialog = new ProgressDialog(this);dialog.setOnKeyListener(new OnKeyListener() {@Overridepublic boolean onKey(DialogInterface dialog, int keyCode,KeyEvent event) {if (keyCode == KeyEvent.KEYCODE_BACK) {finish();}return false;}});dialog.setMessage("正在加载图片请稍后...");dialog.setIndeterminate(true);dialog.setCancelable(true);return dialog;}}return null;}public void initZoom() {/* 取得屏幕分辨率大小 */DisplayMetrics dm = new DisplayMetrics();getWindowManager().getDefaultDisplay().getMetrics(dm);displayWidth = dm.widthPixels;displayHeight = dm.heightPixels;mImageView = (ImageView) findViewById(R.id.myImageView);mImageView.setImageBitmap(bmp);layoutImage = (LinearLayout) findViewById(R.id.layoutImage);mImageView.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {// TODO Auto-generated method stub /** * 在图片上和整个view上同时添加点击监听捕捉屏幕 * 点击事件，来显示放大缩小按钮 * */zoom.setVisibility(View.VISIBLE);mHandler.removeCallbacks(task);mHandler.postDelayed(task, showTime);}});layoutImage.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {// TODO Auto-generated method stubzoom.setVisibility(View.VISIBLE);mHandler.removeCallbacks(task);mHandler.postDelayed(task, showTime);}});zoom = (ZoomControls) findViewById(R.id.zoomcontrol);zoom.setIsZoomInEnabled(true);zoom.setIsZoomOutEnabled(true);// 图片放大zoom.setOnZoomInClickListener(new OnClickListener() {public void onClick(View v) {big();}});// 图片减小zoom.setOnZoomOutClickListener(new OnClickListener() {public void onClick(View v) {small();}});zoom.setVisibility(View.VISIBLE);mHandler.postDelayed(task, showTime);}@Overridepublic boolean onTouchEvent(MotionEvent event) {// TODO Auto-generated method stub /** * 在图片上和整个view上同时添加点击监听捕捉屏幕 * 点击事件，来显示放大缩小按钮 * */zoom.setVisibility(View.VISIBLE);mHandler.removeCallbacks(task);mHandler.postDelayed(task, showTime);return false;}@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event) {// TODO Auto-generated method stubsuper.onKeyDown(keyCode, event);return true;}/* 图片缩小的method */private void small() {--zoomNumber;int bmpWidth = bmp.getWidth();int bmpHeight = bmp.getHeight();Log.i("","bmpWidth = " + bmpWidth + ", bmpHeight = " + bmpHeight);/* 设置图片缩小的比例 */double scale = 0.8;/* 计算出这次要缩小的比例 */scaleWidth = (float) (scaleWidth * scale);scaleHeight = (float) (scaleHeight * scale);/* 产生reSize后的Bitmap对象 */Matrix matrix = new Matrix();matrix.postScale(scaleWidth, scaleHeight);Bitmap resizeBmp = Bitmap.createBitmap(bmp, 0, 0, bmpWidth, bmpHeight,matrix, true);mImageView.setImageBitmap(resizeBmp);/* 限制缩小尺寸 */if ((scaleWidth * scale * bmpWidth < bmpWidth / 4|| scaleHeight * scale * bmpHeight > bmpWidth /4|| scaleWidth * scale * bmpWidth > displayWidth / 5|| scaleHeight * scale * bmpHeight > displayHeight / 5)&&(zoomNumber==-1) ){zoom.setIsZoomOutEnabled(false);} else {zoom.setIsZoomOutEnabled(true);}zoom.setIsZoomInEnabled(true);System.gc();}/* 图片放大的method */private void big() {++zoomNumber;int bmpWidth = bmp.getWidth();int bmpHeight = bmp.getHeight();/* 设置图片放大的比例 */double scale = 1.25;/* 计算这次要放大的比例 */scaleWidth = (float) (scaleWidth * scale);scaleHeight = (float) (scaleHeight * scale);/* 产生reSize后的Bitmap对象 */Matrix matrix = new Matrix();matrix.postScale(scaleWidth, scaleHeight);Bitmap resizeBmp = Bitmap.createBitmap(bmp, 0, 0, bmpWidth, bmpHeight,matrix, true);mImageView.setImageBitmap(resizeBmp);/* 限制放大尺寸 */if (scaleWidth * scale * bmpWidth > bmpWidth * 4|| scaleHeight * scale * bmpHeight > bmpWidth * 4|| scaleWidth * scale * bmpWidth > displayWidth * 5|| scaleHeight * scale * bmpHeight > displayHeight * 5) {zoom.setIsZoomInEnabled(false);} else {zoom.setIsZoomInEnabled(true);}zoom.setIsZoomOutEnabled(true);System.gc();}}