Develop Reference

How to programmatically cancel the OnTouchListener callback even if the user haven't released the touch from a view in Android?

I am working on an Audio Recording App. It works in a way that when the user presses and moves the record button, the button moves along with the finger. I have created a boundary and when the finger crosses that boundary I want the button to perform the hide() animation and get back to it orginal position.
The whole process works fine if the MotionEvent.ACTION_UP or MotionEvent.ACTION_CANCEL event is occurred, but the hide() operation is not occurring even if the touch crosses the boundary. The button plays a back and forth motion sometimes when it is outside the boundary. The touch event is still being called even if I set the visibility of the view to false.
I get the output in the logcat as well (Log.e("MSG","boundary crossed");).
This is the code:
int recordButtonStartX;
microPhoneListner=new View.OnTouchListener() {
#Override
public boolean onTouch(View v, final MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
recordButtonStartX = (int) event.getX();
this.floatingRecordButton.display(event.getX());
}
break;
case MotionEvent.ACTION_CANCEL:
case MotionEvent.ACTION_UP:
this.floatingRecordButton.hide(event.getX());
break;
case MotionEvent.ACTION_MOVE:
int tempX = (int) event.getX();
if ((recordButtonStartX - tempX) > 200) {
Log.e("MSG","boundary crossed");
this.floatingRecordButton.hide(event.getX());
}
else
{
this.floatingRecordButton.moveTo(event.getX());
}
break;
}
recordMsgButton.setOnTouchListener(microPhoneListner);

To release the onTouchListener for any View set the listener to null.
recordMsgButton.setOnTouchListener(null);
or
After your condition satisfied you can set other listener to that View.
Make another listener
public final OnTouchListener mTouchListener = new OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent rawEvent) {
return false;
}
};
When you want to disable the listener then set other listener to that view
v.setOnTouchListener(mTouchListener);

onTouchListener in Android will detect touch on all parent view

I have
RelativeLayout
A---BIG IMAGE
B---MEDIUM IMAGE
C---SMALL IMAGE
The picture is looking like this
I have used below java code
#Override
public boolean onTouch(View v, MotionEvent event) {
switch (v.getId()) {
// LEFT
case R.id.tblLOne:
System.out.println("IMG_L_A");
playBeep(TABLA_L_BIG);
changeLeftDrum();
break;
case R.id.tblLTwo:
System.out.println("IMG_L_B");
playBeep(TABLA_L_MID);
changeLeftDrum();
break;
case R.id.tblLThree:
System.out.println("IMG_L_C");
playBeep(TABLA_L_SMALL);
changeLeftDrum();
break;
return false;
}
return true;
}
Problem is that whenever I click on small (BLACK) Image
I got following output
IMG_L_A
IMG_L_B
IMG_L_C
Whenever I click on Middle Image I got
IMG_L_A
IMG_L_B
On OuterImage big image
IMG_L_A
Why I am getting it's all behind ImageView's OnTouch Method
It is working perfect with onClick but not with OnTouch

It's because the views are stacked on top of each other.
The important point here is to know the importance of the Boolean flag that you return from your onTouchListener. The boolean flag tells android if the event was consumed or not.
Suppose, you touch tblRthree, the case R.id.tblLThree executes, but then since you return false, it appears to android that the event was not consumed and this event bubbles up to the tblRTwo view which is just behind tblRthree view, which executes the same listener for the case R.id.tblLTwo but then again you return false so, it bubbles up to view tblROne and all three cases execute.
You should return true whenever you consume the event, and false when you don't.

onTouch method will be called in multiple events, all you need is to check whether it is MotionEvent.ACTION_DOWN or not.
So, it will look something like this:
#Override
public boolean onTouch(View v, MotionEvent event) {
if(event.getAction()!=MotionEvent.ACTION_DOWN)
{
return false;//we are not going to handle it
}
switch (v.getId()) {
// LEFT
case R.id.tblLOne:
System.out.println("IMG_L_A");
playBeep(TABLA_L_BIG);
changeLeftDrum();
break;
case R.id.tblLTwo:
System.out.println("IMG_L_B");
playBeep(TABLA_L_MID);
changeLeftDrum();
break;
case R.id.tblLThree:
System.out.println("IMG_L_C");
playBeep(TABLA_L_SMALL);
changeLeftDrum();
break;
}
return true;//we have handled it
}

How to get android activity or controls touch count?

I want to get activity or any control element's touch counts.
Like Android 4.2 on nexus Developer options Enable while touching 7 times.
What is the suitable event to handle it ?

You are getting 2 count's because the touch event are called every time a touch event is snet, like tump down and tump up (for example)
#Override
public boolean onTouchEvent(MotionEvent event) {
int action = MotionEventCompat.getActionMasked(event);
switch (action) {
case MotionEvent.ACTION_DOWN:
//add here the counter if you want when screen pressed
break;
case MotionEvent.ACTION_UP:
//add here the counter if you want when touch released
break;
default:
return super.onTouchEvent(event);
}
}

You can use a View.OnTouchListener, overriding the onTouch method :
#Override
public boolean onTouch(final View v, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
// increment counter
break;
}
}

Android onTouch with onClick and onLongClick

I've got a custom view which acts like a button. I want to change the background when user press it, revert the background to original when user moves the finger outside or release it and I also want to handle onClick/onLongClick events. The problem is that onTouch requires me to return true for ACTION_DOWN or it won't send me the ACTION_UP event. But if I return true the onClick listener won't work.
I thought I solved it by returning false in onTouch and registering onClick - it somehow worked, but was kinda against the docs. I've just received a message from an user telling me that he's not able to long-click on the button, so I'm wondering what's wrong here.
Part of the current code:
public boolean onTouch(View v, MotionEvent evt)
{
switch (evt.getAction())
{
case MotionEvent.ACTION_DOWN:
{
setSelection(true); // it just change the background
break;
}
case MotionEvent.ACTION_CANCEL:
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_OUTSIDE:
{
setSelection(false); // it just change the background
break;
}
}
return false;
}
public void onClick(View v)
{
// some other code here
}
public boolean onLongClick(View view)
{
// just showing a Toast here
return false;
}
// somewhere else in code
setOnTouchListener(this);
setOnClickListener(this);
setOnLongClickListener(this);
How do I make them work together correctly?
Thanks in advance

onClick & onLongClick is actually dispatched from View.onTouchEvent.
if you override View.onTouchEvent or set some specific View.OnTouchListener via setOnTouchListener,
you must care for that.
so your code should be something like:
public boolean onTouch(View v, MotionEvent evt)
{
// to dispatch click / long click event,
// you must pass the event to it's default callback View.onTouchEvent
boolean defaultResult = v.onTouchEvent(evt);
switch (evt.getAction())
{
case MotionEvent.ACTION_DOWN:
{
setSelection(true); // just changing the background
break;
}
case MotionEvent.ACTION_CANCEL:
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_OUTSIDE:
{
setSelection(false); // just changing the background
break;
}
default:
return defaultResult;
}
// if you reach here, you have consumed the event
return true;
}

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;
}
});