我的布局中有两个图像。我需要放大我触摸的那个图像。我们知道 Frame 一次只能显示一个视图。那么如何分别对每个图像视图执行缩放？我的 xml 文件：
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<ImageView
android:id="@+id/imageView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center"
android:src="@drawable/image1" />
<ImageView
android:id="@+id/imageView2"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center" android:src="@drawable/image2"
/>
</FrameLayout>
活动文件：
public class MyActivity extends Activity implements OnTouchListener
{
private static final String TAG = "Touch";
// These matrices will be used to scale points of the image
Matrix matrix = new Matrix();
Matrix savedMatrix = new Matrix();
// The 3 states (events) which the user is trying to perform
static final int NONE = 0;
static final int DRAG = 1;
static final int ZOOM = 2;
int mode = NONE;
// these PointF objects are used to record the point(s) the user is touching
PointF start = new PointF();
PointF mid = new PointF();
float oldDist = 1f;
private ImageView iv1;
private ImageView iv2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
iv1 = ((ImageView)findViewById(R.id.imageView1));
iv1.setOnTouchListener(this);
iv2 = ((ImageView)findViewById(R.id.imageView2));
iv2.setOnTouchListener(this);
}
@Override
public boolean onTouch(View v, MotionEvent event) {
switch (v.getId()) {
case R.id.imageView1:
zoomImageView(v, event);
break;
case R.id.imageView2:
zoomImageView(v, event);
break;
default:
break;
}
return true;
}
private boolean zoomImageView(View v, MotionEvent event) {
ImageView view = (ImageView) v;
view.setScaleType(ImageView.ScaleType.MATRIX);
float scale;
switch (event.getAction() & 255)
{
case MotionEvent.ACTION_DOWN: // first finger down only
savedMatrix.set(matrix);
start.set(event.getX(), event.getY());
Log.d(TAG, "mode=DRAG"); // write to LogCat
mode = DRAG;
break;
case MotionEvent.ACTION_UP: // first finger lifted
case 6: // second finger lifted
mode = NONE;
Log.d(TAG, "mode=NONE");
break;
case 5: // first and second finger down
oldDist = spacing(event);
Log.d(TAG, "oldDist=" + oldDist);
if (oldDist > 5f) {
savedMatrix.set(matrix);
midPoint(mid, event);
mode = ZOOM;
Log.d(TAG, "mode=ZOOM");
}
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG)
{
matrix.set(savedMatrix);
matrix.postTranslate(event.getX() - start.x, event.getY() - start.y); // create the transformation in the matrix of points
}
else if (mode == ZOOM)
{
// pinch zooming
float newDist = spacing(event);
Log.d(TAG, "newDist=" + newDist);
if (newDist > 5f)
{
matrix.set(savedMatrix);
scale = newDist / oldDist; // setting the scaling of the
// matrix...if scale > 1 means
// zoom in...if scale < 1 means
// zoom out
matrix.postScale(scale, scale, mid.x, mid.y);
}
}
break;
}
view.setImageMatrix(matrix); // display the transformation on screen
return true; // indicate event was handled
}
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);
}
/*
* --------------------------------------------------------------------------
* Method: midPoint Parameters: PointF object, MotionEvent Returns: void
* Description: calculates the midpoint between the two fingers
* ------------------------------------------------------------
*/
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);
}
}
现在我只能缩放顶部的 image1。如何在触摸 image2 时获得底部图像的缩放功能？我应该能够缩放我触摸的图像。请帮我。