Develop Reference

Android - OnTouchListener not firing if already pressing screen

I have a RelativeLayout with a single ImageView inside of it. The ImageView has an OnTouchListener attached to it which is working perfectly fine if I just press the ImageView. The problem I'm having though is that if I press and hold in the empty space outside of the ImageView and then try to press the ImageView the touch listener doesn't fire. It seems like the layout is absorbing the touch events somehow. Any ideas on how I could fix this?

The action defined by you here is a Multi-touch gesture. Go through this doc to know how to handle this type of actions.
Also take a look at the ACTION_POINTER_DOWN action define in MotionEvent. This is the event that will get called when additional fingers come down.

you mout use this code:
imageView.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()){
case MotionEvent.ACTION_DOWN:
//your code
break;
case MotionEvent.ACTION_UP:
//your code
break;
case MotionEvent.ACTION_MOVE:
//your code
break;
default:
//your code
break;
}
return true;
}
});

Touching the screen while onTouch() is already being called

When I touch the screen and move my finger I do something (pullanimation1 and 2) and when I release the screen I do something else (fireanimation1 and 2). Sometimes, the user might touch the screen while pullAnimation or fireAnimation is running, I get errors as the animation then run several times. I would like to make sure the animations won't run more then once when the user touch again the screen.
NB: pullAnimation1 and 2, fireAnimation 1 and 2 are AnimationDrawable
Here is what I've done :
image2.setOnTouchListener(new OnTouchListener(){
#Override
public boolean onTouch(View arg0, MotionEvent arg1) {
boolean bool=false;
boolean bool2=true;
int action = arg1.getAction() & MotionEvent.ACTION_MASK;
switch (action) {
case MotionEvent.ACTION_DOWN:
if (bool2) {
startAnimation(pullAnimation1,pullAnimation2);
bool=true;
}
break;
case MotionEvent.ACTION_MOVE:
if (bool2==true){
Log.w("GAMEACTIVITY","move");
bool=true;
bool2=false;
}
break;
case MotionEvent.ACTION_UP:
startAnimation(fireAnimation1,fireAnimation2);
bool=false;
doPhotoTask();
bool2=false;
break;
}
return bool;
}
});

I think you should be able to use the hasStarted() and hasEnded() methods to determine if your animation is currently going. See the docs for more
Some if statement like this might work:
if((fireAnimation1.hasStarted() == false) || (fireAnimation1.hasEnded == true()){
startAnimation(fireAnimation1, fireAnimation2);
}
I imagine you may also need to use reset() after it is done playing in order or the methods to return proper values next time touch happens.
EDIT:
AnimationDrawable has an isRunning() method, which makes it even easier than View animations.
if(fireAnimation1.isRunning() == false){
startAnimation(fireAnimation1, fireAnimation2);
}

Android: Long touch on Button while MotionEvent.ACTION_MOVE

Ok... in my app i update the layout on MotionEvent.ACTION_DOWN and then i check the motion event coordinates to locate my buttons. I can show a toast when finger is released on different buttons. The problem is i need a long touch on my buttons to call another action without conflicting with the MotionEvent.ACTION_UP. Implemented a long click handler but since i don't 'click' its not working. Hope you guys understand my problem.
Whats the best way to get my app working as intended?
My class implements OnTouchListener, OnGestureListener
#Override
public boolean onTouch(View v, MotionEvent event) {
switch(event.getAction()){
case MotionEvent.ACTION_DOWN:
// UPDATE LAYOUT
break;
case MotionEvent.ACTION_UP:
// GET BUTTON X Y
if (x and y match the button location){
// DO ACTION
}else{
// DO NOTHING
}
// CHANGE LAYOUT TO INITIAL STATE
break;
case MotionEvent.ACTION_MOVE:
break;
}
return false;
mybutton.setOnLongClickListener(new OnLongClickListener() {
#Override
public boolean onLongClick(View v) {
// DO STUFF
return true;
}
});
}

just try to return false in your onTouch(...) method and use onLongClickListener(...) as usual

how to rotate an image in both directions in android

hi i need to rotate an ImageView in my app on touch
and i am using the following code
public android.view.View.OnTouchListener onTableTouched = new android.view.View.OnTouchListener(){
public boolean onTouch(View v, MotionEvent evt) {
WrapMotionEvent event = WrapMotionEvent.wrap(evt);
ImageView view = (ImageView) v;
// Dump touch event to log
dumpEvent(event);
//
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
break;
case MotionEvent.ACTION_POINTER_DOWN:
mode = NONE;
break;
case MotionEvent.ACTION_UP:
break;
case MotionEvent.ACTION_MOVE:
if(mode == NONE){
updateRotation();
}
break;
}
return true;
}
};
private void updateRotation()
{
matrix.postRotate(10);
Bitmap redrawnBitmap = Bitmap.createBitmap(itembmp, 0, 0,itembmp.getWidth(), itembmp.getHeight(), matrix, true);
itembmp=redrawnBitmap;
image.setImageBitmap(itembmp);
}
but by using this i can rotate the image in clock-direction only.
But i need to rotate the image in both directions .
How to do that.

I would make two functions, one called updateRotationClockwise, one called updateRotationCounterClockWise.
In clockwise, it should stay:
matrix.postRotate(10);
In counterclockwise, it should say:
matrix.postRotate(350);

I am in process of developing this logic.
1. Difference in angle. one needs to also check other boundary conditions for more accuracy.
2. Instead of handling touch actions. I used in build ScaleGestureDetector class for information.
In onScaleBegin assuming I get the event using a setter (called in on touch) in the OnScaleGestureListener.
before=gety/getx;
In on ScaleEnd
after=gety/getx;
thus difference is tan-1(before)-tan-1(after)
if +tive anticlockwise -tive clockwise.
It is not so accurate I am adding conditions but one can try this out.

from the class ClockView you can find the method for rotation for your bitmap image
https://github.com/jselbie/xkcdclock

How to get a continuous Touch Event?

My class extends View and I need to get continuous touch events on it.
If I use:
public boolean onTouchEvent(MotionEvent me) {
if(me.getAction()==MotionEvent.ACTION_DOWN) {
myAction();
}
return true;
}
... the touch event is captured once.
What if I need to get continuous touches without moving the finger?
Please, tell me I don't need to use threads or timers. My app is already too much heavy.
Thanks.

Use if(me.getAction() == MotionEvent.ACTION_MOVE). It's impossible to keep a finger 100% completely still on the screen so Action_Move will get called every time the finger moves, even if it's only a pixel or two.
You could also listen for me.getAction() == MotionEvent.ACTION_UP - until that happens, the user must still have their finger on the screen.

You need to set this properties for the element
android:focusable="true"
android:clickable="true"
if not, just produce the down action.

Her is the simple code snippet which shows that how you can handle the continues touch event. When you touch the device and hold the touch and move your finder, the Touch Move action performed.
#Override
public boolean onTouchEvent(MotionEvent event) {
float x = event.getX();
float y = event.getY();
if(isTsunami){
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
// Write your code to perform an action on down
break;
case MotionEvent.ACTION_MOVE:
// Write your code to perform an action on contineus touch move
break;
case MotionEvent.ACTION_UP:
// Write your code to perform an action on touch up
break;
}
}
return true;
}

Try this. It works to me:
public static OnTouchListener loadContainerOnTouchListener() {
OnTouchListener listener = new OnTouchListener(){
#Override
public boolean onTouch(View v, MotionEvent event) {
LinearLayout layout = (LinearLayout)v;
for(int i =0; i< layout.getChildCount(); i++)
{
View view = layout.getChildAt(i);
Rect outRect = new Rect(view.getLeft(), view.getTop(), view.getRight(), view.getBottom());
if(outRect.contains((int)event.getX(), (int)event.getY()))
{
Log.d(this.getClass().getName(), String.format("Over view.id[%d]", view.getId()));
}
}
}
Remember: the listener you´ll set must be a container layout (Grid, Relative, Linear).
LinearLayout layout = findViewById(R.id.yourlayoutid);
layout.setOnTouchListener(HelperClass.loadContainerOnTouchListener());

This might help,
requestDisallowInterceptTouchEvent(true);
on the parent view, like this -
#Override
public boolean onTouch(View view, MotionEvent motionEvent) {
view.getParent().requestDisallowInterceptTouchEvent(true);
switch(motionEvent.getAction()){
}
return false;
}

I was making a game with a custom view used as a thumb control. . . here is what I did
float x = 0, y = 0;
#Override
public boolean onTouchEvent(MotionEvent event) {
x = event.getX();
y = event.getY();
// handle touch events with
switch( event.getActionMasked() ) {
case MotionEvent.ACTION_DOWN :
if(cont)
{
// remove any previous callbacks
removeCallbacks(contin);
// post new runnable
postDelayed(contin, 10);
}
invalidate();
return true;
case MotionEvent.ACTION_MOVE :
if(!cont && thumbing != null)
{
// do non-continuous operations here
}
invalidate();
return true;
case MotionEvent.ACTION_UP :
// set runnable condition to false
x = 0;
// remove the callbacks to the thread
removeCallbacks(contin);
invalidate();
return true;
default :
return super.onTouchEvent(event);
}
}
public boolean cont = false;
// sets input to continuous
public void set_continuous(boolean b) { cont = b; }
public Runnable contin = new Runnable()
{
#Override
public void run() {
if(x != 0)
{
// do continuous operations here
postDelayed(this, 10);
}
}
};
A quick note however, make sure in your main activity that is calling this view removes the callbacks manually via the onPause method as follows
#Override
protected void onPause() {
if(left.cont) left.removeCallbacks(left.contin);
if(right.cont) right.removeCallbacks(left.contin);
super.onPause();
}
That way if you pause and come back touch events aren't being handled twice and the view is free from it's thread's overhead.
** tested on Samsung Galaxy S3 with hardware acceleration on **

All these answer are partially correct but they do not resolve in the right way the problem.
First of all, for everyone out there that decide to track when the event is ACTION_MOVE. Well that works only guess when? When user move his finger, so could if you decide to implement a custom thumb control is okay but for a normal custom button that's not the case.
Second, using a flag inside ACTION_DOWN and check it in ACTION_UP seems the logic way to do it, but as Clusterfux find out if you implement a while(!up_flag) logic you get stuck into troubles ;)
So the proper way to do it is mentioned here:
Continuous "Action_DOWN" in Android
Just keep in mind that if the logic you're going to write during the continuous press has to modify the UI in some way, you have to do it from the main thread in all the other cases it's better use another thread.

You can use the below code snippet as a reference in which I used the background to detect if the screen is held or not...
Main_Layout.setOnTouchListener(new View.OnTouchListener() {
#SuppressLint("ResourceAsColor")
#Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_MOVE:
Main_Layout.setBackgroundColor(R.color.green);
event.setAction(MotionEvent.ACTION_DOWN);
break;
default:
Main_Layout.setBackgroundColor(R.color.blue);
break;
}
return false;
}
});