在android中显示大型图像并进行缩放
我使用下面的代码来显示一个大位图(5000x3000),它可以很好地工作,但我不能让我的生活得到挤压和缩放工作 基本上我想从SD卡加载图像显示它,然后放大,这样我就可以看到细节 有人有什么想法吗 标记在android中显示大型图像并进行缩放,android,zooming,pinch,Android,Zooming,Pinch,我使用下面的代码来显示一个大位图(5000x3000),它可以很好地工作,但我不能让我的生活得到挤压和缩放工作 基本上我想从SD卡加载图像显示它,然后放大,这样我就可以看到细节 有人有什么想法吗 标记 导入android.app.Activity; 导入android.graphics.Bitmap; 导入android.graphics.BitmapFactory; 导入android.graphics.Matrix; 导入android.graphics.PointF; 导入android.
导入android.app.Activity;
导入android.graphics.Bitmap;
导入android.graphics.BitmapFactory;
导入android.graphics.Matrix;
导入android.graphics.PointF;
导入android.os.Bundle;
导入android.util.FloatMath;
导入android.util.Log;
导入android.view.MotionEvent;
导入android.view.view;
导入android.view.view.OnTouchListener;
导入android.widget.ImageView;
公共类Touch扩展了活动实现OnTouchListener{
私有静态最终字符串TAG=“Touch”;
//这些矩阵将用于移动和缩放图像
矩阵=新矩阵();
矩阵savedMatrix=新矩阵();
//我们可能处于这三种状态之一
静态最终int NONE=0;
静态最终整数阻力=1;
静态最终整数缩放=2;
int模式=无;
//记住一些关于缩放的事情
PointF start=新的PointF();
PointF mid=新的PointF();
浮动oldDist=1f;
@凌驾
创建时的公共void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ImageView jpgView=(ImageView)findViewById(R.id.jpgView);
字符串myJpgPath=“/sdcard/Datafiles/Images/DSC_3509.JPG”;//使用您自己的JPG文件更新
BitmapFactory.Options=new-BitmapFactory.Options();
options.inSampleSize=2;
位图bm=BitmapFactory.decodeFile(myJpgPath,选项);
jpgView.setImageBitmap(bm);
ImageView=(ImageView)findViewById(R.id.jpgview);
view.setOnTouchListener(这个);
// ...
//对付纸杯蛋糕虫
矩阵.setTranslate(1f,1f);
视图.setImageMatrix(矩阵);
}
公共布尔onTouch(视图v、MotionEvent和rawEvent){
WrapMotionEvent=WrapMotionEvent.wrap(rawEvent);
// ...
ImageView视图=(ImageView)v;
//将触摸事件转储到日志
dumpEvent(事件);
//在这里处理触摸事件。。。
开关(event.getAction()&MotionEvent.ACTION\u掩码){
case MotionEvent.ACTION\u DOWN:
savedMatrix.set(矩阵);
set(event.getX(),event.getY());
Log.d(标记“mode=DRAG”);
模式=拖动;
打破
case MotionEvent.ACTION\u指针\u向下:
oldDist=间距(事件);
Log.d(标记“oldDist=“+oldDist”);
如果(旧区>10f){
savedMatrix.set(矩阵);
中点(中点,事件);
模式=缩放;
Log.d(标记“mode=ZOOM”);
}
打破
case MotionEvent.ACTION\u UP:
case MotionEvent.ACTION\u指针\u向上:
模式=无;
Log.d(标记“mode=NONE”);
打破
case MotionEvent.ACTION\u移动:
如果(模式==拖动){
// ...
矩阵集(savedMatrix);
postTranslate(event.getX()-start.x,
event.getY()-start.y);
}
else if(模式==缩放){
float newDist=间距(事件);
Log.d(标记“newDist=“+newDist”);
如果(新距离>10f){
矩阵集(savedMatrix);
浮动比例=新距离/旧距离;
矩阵。后标度(标度、标度、中x、中y);
}
}
打破
}
视图.setImageMatrix(矩阵);
返回true;//指示事件已处理
}
/**在LogCat视图中显示事件以进行调试*/
私有void dumpEvent(WrapMotionEvent事件){
// ...
字符串名称[]={“向下”、“向上”、“移动”、“取消”、“外部”,
“指针向下”、“指针向上”、“7?”、“8?”、“9?”;
StringBuilder sb=新的StringBuilder();
int action=event.getAction();
int actionCode=action&MotionEvent.action\u掩码;
附加(名称[动作代码]);
如果(actionCode==MotionEvent.ACTION\u指针\u向下
||actionCode==MotionEvent.ACTION(指针向上){
某人追加(“(pid”)。追加(
动作>>MotionEvent.action\u指针\u ID\u移位);
某人加上(“)”;
}
某人加上(“[”);
for(int i=0;i 你有没有考虑使用<代码> WebVIEW/CODE >并使用它内置的缩放功能?我不能说为什么捏不起作用,但是假设这是整个代码,它使用固定的样本大小为2,所以当你放大时,你将看不到图像的细节。我编写了一个库,在放大时加载高分辨率的平铺,这可能会对您有所帮助。
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.os.Bundle;
import android.util.FloatMath;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.ImageView;
public class Touch extends Activity implements OnTouchListener {
private static final String TAG = "Touch";
// These matrices will be used to move and zoom image
Matrix matrix = new Matrix();
Matrix savedMatrix = new Matrix();
// We can be in one of these 3 states
static final int NONE = 0;
static final int DRAG = 1;
static final int ZOOM = 2;
int mode = NONE;
// Remember some things for zooming
PointF start = new PointF();
PointF mid = new PointF();
float oldDist = 1f;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ImageView jpgView = (ImageView)findViewById(R.id.jpgview);
String myJpgPath = "/sdcard/Datafiles/Images/DSC_3509.JPG"; //UPDATE WITH YOUR OWN JPG FILE
BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 2;
Bitmap bm = BitmapFactory.decodeFile(myJpgPath, options);
jpgView.setImageBitmap(bm);
ImageView view = (ImageView) findViewById(R.id.jpgview);
view.setOnTouchListener(this);
// ...
// Work around a Cupcake bug
matrix.setTranslate(1f, 1f);
view.setImageMatrix(matrix);
}
public boolean onTouch(View v, MotionEvent rawEvent) {
WrapMotionEvent event = WrapMotionEvent.wrap(rawEvent);
// ...
ImageView view = (ImageView) v;
// Dump touch event to log
dumpEvent(event);
// Handle touch events here...
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
savedMatrix.set(matrix);
start.set(event.getX(), event.getY());
Log.d(TAG, "mode=DRAG");
mode = DRAG;
break;
case MotionEvent.ACTION_POINTER_DOWN:
oldDist = spacing(event);
Log.d(TAG, "oldDist=" + oldDist);
if (oldDist > 10f) {
savedMatrix.set(matrix);
midPoint(mid, event);
mode = ZOOM;
Log.d(TAG, "mode=ZOOM");
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
Log.d(TAG, "mode=NONE");
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG) {
// ...
matrix.set(savedMatrix);
matrix.postTranslate(event.getX() - start.x,
event.getY() - start.y);
}
else if (mode == ZOOM) {
float newDist = spacing(event);
Log.d(TAG, "newDist=" + newDist);
if (newDist > 10f) {
matrix.set(savedMatrix);
float scale = newDist / oldDist;
matrix.postScale(scale, scale, mid.x, mid.y);
}
}
break;
}
view.setImageMatrix(matrix);
return true; // indicate event was handled
}
/** Show an event in the LogCat view, for debugging */
private void dumpEvent(WrapMotionEvent event) {
// ...
String names[] = { "DOWN", "UP", "MOVE", "CANCEL", "OUTSIDE",
"POINTER_DOWN", "POINTER_UP", "7?", "8?", "9?" };
StringBuilder sb = new StringBuilder();
int action = event.getAction();
int actionCode = action & MotionEvent.ACTION_MASK;
sb.append("event ACTION_").append(names[actionCode]);
if (actionCode == MotionEvent.ACTION_POINTER_DOWN
|| actionCode == MotionEvent.ACTION_POINTER_UP) {
sb.append("(pid ").append(
action >> MotionEvent.ACTION_POINTER_ID_SHIFT);
sb.append(")");
}
sb.append("[");
for (int i = 0; i < event.getPointerCount(); i++) {
sb.append("#").append(i);
sb.append("(pid ").append(event.getPointerId(i));
sb.append(")=").append((int) event.getX(i));
sb.append(",").append((int) event.getY(i));
if (i + 1 < event.getPointerCount())
sb.append(";");
}
sb.append("]");
Log.d(TAG, sb.toString());
}
/** Determine the space between the first two fingers */
private float spacing(WrapMotionEvent event) {
// ...
float x = event.getX(0) - event.getX(1);
float y = event.getY(0) - event.getY(1);
return FloatMath.sqrt(x * x + y * y);
}
/** Calculate the mid point of the first two fingers */
private void midPoint(PointF point, WrapMotionEvent event) {
// ...
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2, y / 2);
}
}