我尝试通过展开/捏合手势和相对布局上的拖放功能来实现放大/缩小。
这是我的 OnPinchListener 处理缩放效果的代码。mainView是布局xml文件中定义的RelativeLayout 。
我在fakeview中实现了触摸监听器，它应该在所有视图的前面。触摸事件会根据代码改变主视图。
我想问是否可以在缩放后得到实际的左、上、宽和高？它总是返回 0,0 为左和上，以及缩放后的原始宽度和高度。
非常感谢！
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/linear_layout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<RelativeLayout
android:id="@+id/zoomable_relative_layout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
>
<ImageView
android:id="@+id/imageView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:src="@drawable/background" />
</RelativeLayout>
<RelativeLayout
android:id="@+id/relative_layout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:orientation="vertical" >
</RelativeLayout>
</RelativeLayout>
public class MainActivity extends Activity {
//ZoomableRelativeLayout mainView = null;
RelativeLayout mainView = null;
RelativeLayout rl = null;
public static final String TAG = "ZoomText."
+ MainActivity.class.getSimpleName();
private int offset_x;
private int offset_y;
private boolean dragMutex = false;
RelativeLayout fakeView = null;
float width = 0, height = 0;
private OnTouchListener listener = new OnTouchListener() {
@Override
public boolean onTouch(View arg0, MotionEvent event) {
// Log.e(TAG, event + "");
// Log.e(TAG, "Pointer Count = "+event.getPointerCount());
Log.e(TAG,
event.getX() + "," + event.getY() + "|" + mainView.getX()
+ "(" + mainView.getWidth() + "),"
+ mainView.getY() + "(" + mainView.getHeight()
+ ")");
if (event.getX() >= mainView.getLeft()
&& event.getX() <= mainView.getLeft() + mainView.getWidth()
&& event.getY() >= mainView.getTop()
&& event.getY() <=mainView.getTop() + mainView.getHeight())
if (event.getPointerCount() > 1) {
return scaleGestureDetector.onTouchEvent(event);
} else {
return llListener.onTouch(arg0, event);
}
return false;
}
};
private ScaleGestureDetector scaleGestureDetector;
private OnTouchListener llListener = new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
// Log.d(TAG, event + ",LL");
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
offset_x = (int) event.getX();
offset_y = (int) event.getY();
// Log.e(TAG, offset_x + "," + offset_y);
dragMutex = true;
return true;
case MotionEvent.ACTION_MOVE:
// Log.e(TAG, "Finger down");
int x = (int) event.getX() - offset_x;
int y = (int) event.getY() - offset_y;
Log.e(TAG, event.getX() + "," + event.getY());
float _x = mainView.getX();
float _y = mainView.getY();
mainView.setX(_x + x);
mainView.setY(_y + y);
offset_x = (int) event.getX();
offset_y = (int) event.getY();
return true;
case MotionEvent.ACTION_UP:
dragMutex = false;
return true;
}
return false;
}
};
private OnDragListener dragListener = new View.OnDragListener() {
@Override
public boolean onDrag(View arg0, DragEvent arg1) {
Log.e(TAG, "DRAG Listener = " + arg1);
return false;
}
};
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mainView = (RelativeLayout) findViewById(R.id.zoomable_relative_layout);
// mainView.setOnTouchListener(new OnPinchListener());
// mainView.setOnTouchListener(listener);
scaleGestureDetector = new ScaleGestureDetector(this,
new OnPinchListener());
rl = (RelativeLayout) findViewById(R.id.linear_layout);
mainView.setOnDragListener(dragListener);
// mainView.setOnTouchListener(llListener);
fakeView = (RelativeLayout) findViewById(R.id.relative_layout);
fakeView.setOnTouchListener(listener);
}
class OnPinchListener extends SimpleOnScaleGestureListener {
float startingSpan;
float endSpan;
float startFocusX;
float startFocusY;
public boolean onScaleBegin(ScaleGestureDetector detector) {
startingSpan = detector.getCurrentSpan();
startFocusX = detector.getFocusX();
startFocusY = detector.getFocusY();
return true;
}
public boolean onScale(ScaleGestureDetector detector) {
// mainView.scale(detector.getCurrentSpan() / startingSpan,
// startFocusX, startFocusY);
// if(width==0)
// width = mainView.getWidth();
// if(height==0)
// height = mainView.getHeight();
mainView.setPivotX(startFocusX);
mainView.setPivotY(startFocusY);
mainView.setScaleX(detector.getCurrentSpan() / startingSpan);
mainView.setScaleY(detector.getCurrentSpan() / startingSpan);
// LayoutParams para = mainView.getLayoutParams();
// width*=detector.getCurrentSpan() / startingSpan;
// height*=detector.getCurrentSpan() / startingSpan;
// para.width = (int)width;
// para.height = (int)height;
// mainView.setLayoutParams(para);
return true;
}
public void onScaleEnd(ScaleGestureDetector detector) {
//mainView.restore();
mainView.invalidate();
Log.e(TAG, mainView.getLeft()+","+mainView.getRight());
}
}
}