If you're looking for a method like ImageView.setOnGestureListener, there is none. You can go look at the Android source code. Your best option is to handle it in onTouch() of the View object.
This is the simplest GestureDetector I can make.
I have a class called GenesMotionDetector.java. Here's the code for it:
package gene.com.motioneventssample;
import android.app.Activity;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
public class GenesMotionDetector extends Activity implements GestureDetector.OnGestureListener {
private GestureDetector gestureScanner;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.nothing);
gestureScanner= new GestureDetector(getBaseContext(),this);
}
@Override
public boolean onTouchEvent(MotionEvent me) {
System.out.println("Inside onTouchEvent() of GenesMotionDetector.java");
return gestureScanner.onTouchEvent(me);
}
@Override
public boolean onDown(MotionEvent e) {
System.out.println("Inside onDown() of GenesMotionDetector.java");
return true;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
System.out.println("Inside onFling() of GenesMotionDetector.java");
return true;
}
@Override
public void onLongPress(MotionEvent e) {
System.out.println("Inside onLongPress() of GenesMotionDetector.java");
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
System.out.println("Inside onScroll() of GenesMotionDetector.java");
return true;
}
@Override
public void onShowPress(MotionEvent e) {
System.out.println("Inside onShowPress() of GenesMotionDetector.java");
}
@Override
public boolean onSingleTapUp(MotionEvent e) {
System.out.println("Inside onSingleTapUp() of GenesMotionDetector.java");
return true;
}
}
The corresponding XML layout file for that class is nothing.xml. Here's the code for it:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/screen"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/text"
android:background="#17528c"
android:text="testing"
android:layout_width="100dp"
android:layout_height="200dp" />
<ImageView
android:id="@+id/image"
android:background="#f8af20"
android:layout_width="100dp"
android:layout_height="200dp" />
</LinearLayout>
Now, taking the simplest GestureDetector I can make (from above) and modifying it for what you want, I get this:
package gene.com.motioneventssample;
import android.app.Activity;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.widget.ImageView;
public class GenesMotionDetector3 extends Activity implements GestureDetector.OnGestureListener {
private GestureDetector gestureScanner;
ImageView mView3;
View.OnTouchListener gestureListener;
MotionEvent initialME, finalME;
private VelocityTracker mVelocityTracker = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.nothing);
mView3 = (ImageView) findViewById(R.id.image);
// Gesture detection
gestureScanner = new GestureDetector(getBaseContext(), this);
gestureListener = new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
switch(event.getAction()){
case MotionEvent.ACTION_DOWN:
initialME= event;
if(mVelocityTracker == null) {
// Retrieve a new VelocityTracker object to watch the velocity of a motion.
mVelocityTracker = VelocityTracker.obtain();
}
else {
// Reset the velocity tracker back to its initial state.
mVelocityTracker.clear();
}
// Add a user's movement to the tracker.
mVelocityTracker.addMovement(event);
break;
case MotionEvent.ACTION_MOVE:
mVelocityTracker.addMovement(event);
// When you want to determine the velocity, call
// computeCurrentVelocity(). Then call getXVelocity()
// and getYVelocity() to retrieve the velocity for each pointer ID.
mVelocityTracker.computeCurrentVelocity(1000);
break;
case MotionEvent.ACTION_UP:
finalME=event;
break;
case MotionEvent.ACTION_CANCEL:
// Return a VelocityTracker object back to be re-used by others.
mVelocityTracker.recycle();
break;
}
return onFling(initialME, finalME, mVelocityTracker.getXVelocity(), mVelocityTracker.getYVelocity());
//return false;
}
};
mView3.setOnTouchListener(gestureListener);
}
@Override
public boolean onTouchEvent(MotionEvent me) {
System.out.println("Inside onTouchEvent() of GenesMotionDetector.java");
return gestureScanner.onTouchEvent(me);
}
@Override
public boolean onDown(MotionEvent e) {
System.out.println("Inside onDown() of GenesMotionDetector.java");
return true;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
System.out.println("Inside onFling() of GenesMotionDetector.java");
System.out.println("e1= "+ e1);
System.out.println("e2= "+ e2);
System.out.println("velocityX= "+ velocityX);
System.out.println("velocityY= "+ velocityY);
return true;
}
@Override
public void onLongPress(MotionEvent e) {
System.out.println("Inside onLongPress() of GenesMotionDetector.java");
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
System.out.println("Inside onScroll() of GenesMotionDetector.java");
return true;
}
@Override
public void onShowPress(MotionEvent e) {
System.out.println("Inside onShowPress() of GenesMotionDetector.java");
}
@Override
public boolean onSingleTapUp(MotionEvent e) {
System.out.println("Inside onSingleTapUp() of GenesMotionDetector.java");
return true;
}
}
You might as well just handle everything in onTouch(). I'm basically getting the gestures in onTouch and passing it to onFling().
