废话不多说，直接代码。该imageview 只能代码里new出来使用。不能xml布局配置。有空再修改成可以配置使用的。
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.util.FloatMath;
import android.view.MotionEvent;
import android.widget.ImageView;
public class TouchImageView extends ImageView {
float x_down = 0;
float y_down = 0;
PointF start = new PointF();
PointF mid = new PointF();
float oldDist = 1f;
float oldRotation = 0;
Matrix matrix = new Matrix();
Matrix matrix1 = new Matrix();
Matrix savedMatrix = new Matrix();
private static final int NONE = 0;
private static final int DRAG = 1;
private static final int ZOOM = 2;
int mode = NONE;
boolean matrixCheck = false;
int widthScreen;
int heightScreen;
//变换类型
private static final int TYPE_WIDTH = 1;//只变宽度
private static final int TYPE_HIGHT = 2;//只变高度
private static final int TYPE_ALL = 3;//宽高都变
private static final int TYPE_NONE = 4;//无变换
Bitmap gintama;
public TouchImageView(Context ctx, Bitmap bmp, int screenWPix, int screenHPix) {
super(ctx);
gintama = bmp;
widthScreen = screenWPix;
heightScreen = screenHPix;
matrix = new Matrix();
initBitmap();
}
@Override
public void setImageBitmap(Bitmap bm) {
// TODO Auto-generated method stub
gintama = bm;
initBitmap();
}
@Override
public void setImageResource(int resId) {
// TODO Auto-generated method stub
gintama = BitmapFactory.decodeResource(getResources(), resId);
initBitmap();
}
protected void onDraw(Canvas canvas) {
if(gintama == null) return;
canvas.save();
canvas.drawBitmap(gintama, matrix, null);
canvas.restore();
}
private void initBitmap()
{
if(gintama == null) return;
float srcWidth = gintama.getWidth();
float srcHight = gintama.getHeight();
matrix.reset();
//偏移屏幕宽度的10%像素
float offset = widthScreen * 0.1f;
float width = widthScreen - offset;
float hight = heightScreen - offset;
//初始化移动距离
float dx = (widthScreen - srcWidth)/2f;
float dy = (heightScreen - srcHight)/2f;
int type = TYPE_NONE;
float scale = 1f;
if(srcWidth > width)
{
scale = width / srcWidth;
type = TYPE_WIDTH;
if(srcHight > hight)
{
float temp = hight / srcHight;
type = TYPE_ALL;
if(scale > temp)
{
scale = temp;
}
}
}else{
if(srcHight > hight)
{
scale = heightScreen / srcHight;
type = TYPE_HIGHT;
}
}
if(scale != 1f){
//缩放
matrix.postScale(scale, scale);
}
//移动
switch(type)
{
case TYPE_ALL:
case TYPE_HIGHT:
case TYPE_WIDTH:
dx = (widthScreen - srcWidth * scale) / 2f;
dy = (heightScreen - srcHight * scale) / 2f;
break;
}
matrix.postTranslate(dx, dy);
invalidate();
}
private long begin,end;
public boolean onTouchEvent(MotionEvent event) {
if(gintama == null) return super.onTouchEvent(event);
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
mode = DRAG;
begin = System.currentTimeMillis();
x_down = event.getX();
y_down = event.getY();
savedMatrix.set(matrix);
break;
case MotionEvent.ACTION_POINTER_DOWN:
mode = ZOOM;
oldDist = spacing(event);
oldRotation = rotation(event);
savedMatrix.set(matrix);
midPoint(mid, event);
break;
case MotionEvent.ACTION_MOVE:
if (mode == ZOOM) {
matrix1.set(savedMatrix);
float rotation = rotation(event) - oldRotation;
float newDist = spacing(event);
float scale = newDist / oldDist;
matrix1.postScale(scale, scale, mid.x, mid.y);// 縮放
matrix1.postRotate(rotation, mid.x, mid.y);// 旋轉
matrixCheck = matrixCheck();
if (matrixCheck == false) {
matrix.set(matrix1);
invalidate();
}
} else if (mode == DRAG) {
matrix1.set(savedMatrix);
matrix1.postTranslate(event.getX() - x_down, event.getY()
- y_down);// 平移
matrixCheck = matrixCheck();
if (matrixCheck == false) {
matrix.set(matrix1);
invalidate();
}
}
break;
case MotionEvent.ACTION_UP:
end = System.currentTimeMillis();
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
break;
}
//点击时间区分是否是关闭
if((end - begin) < 150)
{
return super.onTouchEvent(event);
}else{
return true;
}
}
private boolean matrixCheck() {
float[] f = new float[9];
matrix1.getValues(f);
// 图片4个顶点的坐标
float x1 = f[0] * 0 + f[1] * 0 + f[2];
float y1 = f[3] * 0 + f[4] * 0 + f[5];
float x2 = f[0] * gintama.getWidth() + f[1] * 0 + f[2];
float y2 = f[3] * gintama.getWidth() + f[4] * 0 + f[5];
float x3 = f[0] * 0 + f[1] * gintama.getHeight() + f[2];
float y3 = f[3] * 0 + f[4] * gintama.getHeight() + f[5];
float x4 = f[0] * gintama.getWidth() + f[1] * gintama.getHeight() + f[2];
float y4 = f[3] * gintama.getWidth() + f[4] * gintama.getHeight() + f[5];
// 图片现宽度
double width = Math.sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
// 缩放比率判断
if (width < widthScreen / 3 || width > widthScreen * 3) {
return true;
}
// 出界判断
if ((x1 < widthScreen / 3 && x2 < widthScreen / 3
&& x3 < widthScreen / 3 && x4 < widthScreen / 3)
|| (x1 > widthScreen * 2 / 3 && x2 > widthScreen * 2 / 3
&& x3 > widthScreen * 2 / 3 && x4 > widthScreen * 2 / 3)
|| (y1 < heightScreen / 3 && y2 < heightScreen / 3
&& y3 < heightScreen / 3 && y4 < heightScreen / 3)
|| (y1 > heightScreen * 2 / 3 && y2 > heightScreen * 2 / 3
&& y3 > heightScreen * 2 / 3 && y4 > heightScreen * 2 / 3)) {
return true;
}
return false;
}
// 触碰两点间距离
private float spacing(MotionEvent event) {
float x = event.getX(0) - event.getX(1);
float y = event.getY(0) - event.getY(1);
return FloatMath.sqrt(x * x + y * y);
}
// 取手势中心点
private void midPoint(PointF point, MotionEvent event) {
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2, y / 2);
}
// 取旋转角度
private float rotation(MotionEvent event) {
double delta_x = (event.getX(0) - event.getX(1));
double delta_y = (event.getY(0) - event.getY(1));
double radians = Math.atan2(delta_y, delta_x);
return (float) Math.toDegrees(radians);
}
}
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