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public class MyImageView extends ImageView implements View.OnTouchListener{
public interface ImageViewVisiable
{
// 其他控件隱藏域顯示囘調函數
public void visiable(int flag);
}
private ImageViewVisiable mImageViewVisiable;
public void setImageViewVisiable(ImageViewVisiable imageViewVisiable)
{
this.mImageViewVisiable = imageViewVisiable;
}
/**
* 变换图片的矩阵
*/
private Matrix matrix;
/**
* 记录图片矩阵状态
*/
private Matrix saveMatrix;
/**
* 起始触摸点
*/
private PointF start;
/**
* 触摸状态
*/
public int MODE = MODE_INIT;
/**
* 初始状态，点击后隐藏标题、评论等
*/
public static final int MODE_INIT = 1;
/**
* 图片为初始大小的满屏状态，未缩放，点击后显现标题、评论等
*/
public static final int MODE_FULLSCREEN = 2;
/**
* 缩放状态
*/
public static final int MODE_ZOOM = 3;
/**
* 拖拽状态
*/
public static final int MODE_DRAG = 4;
private float oldDistance;
private float newDistance;
private PointF midPoint;
/**
* 这一次手指移动后产生的缩放比例，初始是1
*/
private float scale = 1;
/**
* 之前保存的缩放比例，初始是1
*/
private float savedScale = 1;
/**
* 组件
*/
private int mWidth;
private int mHeight;
private Context context;
float left;
float top;
float right;
float bottom;
/** <默认构造函数>
*/
public MyImageView(Context context) {
super(context);
init(context);
}
/** <默认构造函数>
*/
public MyImageView(Context context,AttributeSet attrs) {
super(context,attrs);
init(context);
}
private void init(Context context)
{
this.mWidth = 400;
this.mHeight = 400;
this.context = context;
matrix = new Matrix();
saveMatrix = new Matrix();
start = new PointF();
midPoint = new PointF();
setOnTouchListener(this);
}
private boolean getImageInfo(ImageView view)
{
Drawable mDrawable = null;
if (view != null)
{
mDrawable = view.getDrawable();
if (mDrawable != null)
{
Rect rect = mDrawable.getBounds();
float[] values = new float[9];
matrix.getValues(values);
left = values[2];
top = values[5];
right = left + rect.width() * values[0];
bottom = top + rect.height() * values[0];
}
}
if (mDrawable == null)
{
LogUtil.d("獲取圖片失敗,請檢查是否因為內存吃緊,圖片被回收");
return false;
}
return true;
}
public void postTranslate(MotionEvent event, ImageView view)
{
getImageInfo(view);
LogUtil.d("Move获取当前图片的left:" + left + "|top:" +top + "|right:" + right + "|bottom:" + bottom);
matrix.set(saveMatrix);
float translateX = (event.getX() - start.x);
float translateY = (event.getY() - start.y);
LogUtil.d("把图片平移至:" + translateX + "x" + translateY);
matrix.postTranslate(translateX,translateY);
}
public void stopOutScreen()
{
float translateX = 0;
float translateY = 0;
if (right > mWidth && left < 0)
{
}
else
{
//往左
if (right < mWidth) //当图片宽度已经大于屏幕
{
translateX = mWidth - right ;
}
else if (left > 0)
{
translateX =0 - left;
}
}
if (top < 0 && bottom > mHeight)
{
}
else
{
//往上滑动
if (top <0)
{
translateY = 0 - top;
}
else if (bottom > mHeight)
{
translateY = mHeight -bottom;
}
}
LogUtil.d("图片还原至:" + translateX + "x" + translateY);
matrix.postTranslate(translateX,translateY);
}
public void setPoint(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);
}
/**
* 获取2个触控点距离
*
* @param event
* @return
*/
public float caculateDistance(MotionEvent event)
{
float x = 0;
float y = 0;
try{
x = event.getX(0) - event.getX(1);
y = event.getY(0) - event.getY(1);
}catch(IllegalArgumentException e){
}
return FloatMath.sqrt(x * x + y * y);
}
public void actionDown(ImageView v, MotionEvent event)
{
LogUtil.d("ACTION_DOWN " + MODE);
matrix.set(v.getImageMatrix());
saveMatrix.set(matrix);
// 得到当前点的位置
start.set(event.getX(), event.getY());
// 拖动
if (savedScale > 1)
{
MODE = MODE_DRAG;
}
getImageInfo(v);
v.setImageMatrix(matrix);
}
public void actionMove(ImageView v, MotionEvent event)
{
// 拖动
if (MODE == MODE_DRAG) {
postTranslate(event, v);
}
// 缩放
else if (MODE == MODE_ZOOM) {
newDistance = caculateDistance(event);
if (newDistance > 5f) {
matrix.set(saveMatrix);
scale = newDistance / oldDistance;
matrix.postScale(scale, scale, midPoint.x, midPoint.y);
}
}
v.setImageMatrix(matrix);
}
public void actionPointerDown(ImageView v, MotionEvent event)
{
LogUtil.d("ACTION_POINTER_DOWN " + MODE);
if (MODE == MODE_FULLSCREEN || MODE == MODE_DRAG)
{
oldDistance = caculateDistance(event);
v.setScaleType(ScaleType.MATRIX);
if (oldDistance > 10f)
{
saveMatrix.set(matrix);
setPoint(midPoint, event);
MODE = MODE_ZOOM;
}
}
v.setImageMatrix(matrix);
}
public void actionPointerUp(ImageView v, MotionEvent event)
{
LogUtil.d("ACTION_POINTER_UP " + MODE);
}
public void actionUp(MotionEvent enent)
{
LogUtil.d("ACTION_UP " + MODE);
// 隐藏标题、评论
if (MODE == MODE_INIT)
{
MODE = MODE_FULLSCREEN;
mImageViewVisiable.visiable(GONE);
}
// 显示标题、评论
else if (MODE == MODE_FULLSCREEN)
{
mImageViewVisiable.visiable(VISIBLE);
MODE = MODE_INIT;
}
// 缩放
else if (MODE == MODE_ZOOM)
{
savedScale *= scale;
if (savedScale > 2)
{
setScaleType(ScaleType.FIT_CENTER);
savedScale = 1;
scale = 1;
MODE = MODE_FULLSCREEN;
} else if (savedScale < 1)
{
setScaleType(ScaleType.FIT_CENTER);
savedScale = 1;
scale = 1;
MODE = MODE_FULLSCREEN;
} else if (savedScale == 1)
{
MODE = MODE_FULLSCREEN;
}
}
else if (MODE == MODE_DRAG)
{
stopOutScreen();
}
setImageMatrix(matrix);
}
@Override
public boolean onTouch(View v, MotionEvent event)
{
ImageView view = (ImageView) v;
switch (event.getAction() & MotionEvent.ACTION_MASK)
{
case MotionEvent.ACTION_DOWN:
actionDown(view, event);
break;
case MotionEvent.ACTION_MOVE:
actionMove(view, event);
break;
case MotionEvent.ACTION_POINTER_DOWN:
actionPointerDown(view, event);
break;
case MotionEvent.ACTION_POINTER_UP:
actionPointerUp(view, event);
break;
case MotionEvent.ACTION_UP:
actionUp(event);
break;
}
return true;
}
}
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