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package com.electric.chargingpile.view;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ImageView;
import com.electric.chargingpile.R;
public class ImageShowActivity extends Activity {
private ImageView imageShow;
private static String tag = "ResolvePicture";
private String[] imageUrls;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_image_show);
initView();
}
private void initView() {
imageShow = (ImageView) findViewById(R.id.imageShow);
// Bitmap bitmap = BitmapFactory.decodeResource(getResources(),
// R.drawable.yd1_625);
// imageShow.setImageDrawable(resizeImage2("/storage/emulated/0/alterandroidapp.jpg", 200, 100));
imageUrls = getIntent().getStringArrayExtra("url");
// imageShow.setImageDrawable();
imageShow.setOnTouchListener(new TouchListener());
}
//使用BitmapFactory.Options的inSampleSize参数来缩放
public static Drawable resizeImage2(String path,
int width, int height) {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;//不加载bitmap到内存中
BitmapFactory.decodeFile(path, options);
int outWidth = options.outWidth;
int outHeight = options.outHeight;
options.inDither = false;
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
options.inSampleSize = 1;
if (outWidth != 0 && outHeight != 0 && width != 0 && height != 0) {
int sampleSize = (outWidth / width + outHeight / height) / 2;
Log.d(tag, "sampleSize = " + sampleSize);
options.inSampleSize = sampleSize;
}
options.inJustDecodeBounds = false;
return new BitmapDrawable(BitmapFactory.decodeFile(path, options));
}
public static Drawable resizeImage(Bitmap bitmap, int w, int h) {
Bitmap BitmapOrg = bitmap;
int width = BitmapOrg.getWidth();
int height = BitmapOrg.getHeight();
int newWidth = w;
int newHeight = h;
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
// if you want to rotate the Bitmap
// matrix.postRotate(45);
Bitmap resizedBitmap = Bitmap.createBitmap(BitmapOrg, 0, 0, width,
height, matrix, true);
return new BitmapDrawable(resizedBitmap);
}
private final class TouchListener implements View.OnTouchListener {
/**
* 记录是拖拉照片模式还是放大缩小照片模式
*/
private int mode = 0;// 初始状态
/**
* 拖拉照片模式
*/
private static final int MODE_DRAG = 1;
/**
* 放大缩小照片模式
*/
private static final int MODE_ZOOM = 2;
/**
* 用于记录开始时候的坐标位置
*/
private PointF startPoint = new PointF();
/**
* 用于记录拖拉图片移动的坐标位置
*/
private Matrix matrix = new Matrix();
/**
* 用于记录图片要进行拖拉时候的坐标位置
*/
private Matrix currentMatrix = new Matrix();
/**
* 两个手指的开始距离
*/
private float startDis;
/**
* 两个手指的中间点
*/
private PointF midPoint;
@Override
public boolean onTouch(View v, MotionEvent event) {
/** 通过与运算保留最后八位 MotionEvent.ACTION_MASK = 255 */
switch (event.getAction() & MotionEvent.ACTION_MASK) {
// 手指压下屏幕
case MotionEvent.ACTION_DOWN:
mode = MODE_DRAG;
// 记录ImageView当前的移动位置
currentMatrix.set(imageShow.getImageMatrix());
startPoint.set(event.getX(), event.getY());
break;
// 手指在屏幕上移动，改事件会被不断触发
case MotionEvent.ACTION_MOVE:
// 拖拉图片
if (mode == MODE_DRAG) {
float dx = event.getX() - startPoint.x; // 得到x轴的移动距离
float dy = event.getY() - startPoint.y; // 得到x轴的移动距离
// 在没有移动之前的位置上进行移动
matrix.set(currentMatrix);
matrix.postTranslate(dx, dy);
}
// 放大缩小图片
else if (mode == MODE_ZOOM) {
float endDis = distance(event);// 结束距离
if (endDis > 10f) { // 两个手指并拢在一起的时候像素大于10
float scale = endDis / startDis;// 得到缩放倍数
matrix.set(currentMatrix);
matrix.postScale(scale, scale, midPoint.x, midPoint.y);
}
}
break;
// 手指离开屏幕
case MotionEvent.ACTION_UP:
// 当触点离开屏幕，但是屏幕上还有触点(手指)
case MotionEvent.ACTION_POINTER_UP:
mode = 0;
break;
// 当屏幕上已经有触点(手指)，再有一个触点压下屏幕
case MotionEvent.ACTION_POINTER_DOWN:
mode = MODE_ZOOM;
/** 计算两个手指间的距离 */
startDis = distance(event);
/** 计算两个手指间的中间点 */
if (startDis > 10f) { // 两个手指并拢在一起的时候像素大于10
midPoint = mid(event);
//记录当前ImageView的缩放倍数
currentMatrix.set(imageShow.getImageMatrix());
}
break;
}
imageShow.setImageMatrix(matrix);
return true;
}
/**
* 计算两个手指间的距离
*/
private float distance(MotionEvent event) {
float dx = event.getX(1) - event.getX(0);
float dy = event.getY(1) - event.getY(0);
/** 使用勾股定理返回两点之间的距离 */
return (float) Math.sqrt(dx * dx + dy * dy);
}
/**
* 计算两个手指间的中间点
*/
private PointF mid(MotionEvent event) {
float midX = (event.getX(1) + event.getX(0)) / 2;
float midY = (event.getY(1) + event.getY(0)) / 2;
return new PointF(midX, midY);
}
}
}
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