图片简单放大
先上效果图：
[img]
[/img]
布局文件：
main.xm
MainActivity:
[img]
[/img]
布局文件：
main.xm
<?xml version="1.0" encoding="utf-8"?> <FrameLayout 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/layout1"> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:id="@+id/rl"> <ScrollView xmlns: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"> <HorizontalScrollView android:layout_height="fill_parent" android:layout_width="fill_parent" android:scrollbars="none" android:layout_gravity="center" android:gravity="center" android:id="@+id/hs"> <LinearLayout android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="fill_parent" android:id="@+id/layoutImage" android:layout_gravity="center" android:gravity="center"> <ImageView android: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> <ZoomControls android:id="@+id/zoomcontrol" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerHorizontal="true" android:layout_alignParentBottom="true" /> </RelativeLayout> </FrameLayout>
MainActivity:
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();
}
@Override
protected Dialog onCreateDialog(int id) {
switch (id) {
case LOADING_IMAGE: {
final ProgressDialog dialog = new ProgressDialog(this);
dialog.setOnKeyListener(new OnKeyListener() {
@Override
public 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() {
@Override
public 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() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
zoom.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);
}
@Override
public 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;
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
// TODO Auto-generated method stub
super.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();
}
}