Develop Reference

Android child onTouchListener disabling parent onClick

I have a parent, custom RelativeLayout which inflates two ImageViews: one content image, and a close button in the top right corner.
The issue: I cannot have both the gestures/scaling of the content image functioning AND the close button functioning.
The content image is a custom ImageView subclass (a modification of https://github.com/MikeOrtiz/TouchImageView), which has it's own OnTouchListener to allow for pinch-zooming, and responding to usual gestures.
This OnTouchListener contains the code:
private class PrivateOnTouchListener implements OnTouchListener {
#Override
public boolean onTouch(View v, MotionEvent event) {
mScaleDetector.onTouchEvent(event);
mGestureDetector.onTouchEvent(event);
//....
return true;
Now, if that return is true, the scaling/gestures for the content image works, but the close button onClick is never called, whereas if it's false then the scaling/getures don't work and the onClick can be called.
I don't understand why a return function called AFTER the event is passed to the gesture detector affects (?consumes the event) whether or not the gesture detector works.
Is there a simple way of ensuring the functionality of both child ImageViews, where that return function is false but both detectors still work?
What I've tried:
Ensuring all methods in the gestureDetector return false, so that the event isn't consumed. (The scaleDetector isn't custom, so I haven't done the same there; if you think that's where the problem is let me know)
An onInterceptTouch method in the parent RelativeLayout, but I'm not sure if I implemented that correctly
(Reading around event handling to understand how it works)

How Can I Prevent Activation For Some ListView Items When The Selection Mode Is MultiChoiceModal?

I have a customized GridView populated by a customized BaseAdapter. The selection mode of the GridView is MultiChoiceModal. I want to control which items can be activated when long clicked while still ensuring they respond to (short) click events. BaseAdapter has a method called isEnabled, the perfect solution would be if it had a method isActivatable that behaved analogously. The next best solution would be to intercept long clicks and pass them along to the default handler only when acceptable.
Here are some things that don't work:
Overriding isEnabled in the adapter. This is overkill. In that case, the items cease responding to click events.
Calling setLongClickable for the parent view of each item in the adapter's getView method. This is fraught with problems even if it worked. Needless to say it doesn't. Likely a byproduct of the selection mode.
Setting a custom onLongClickListener for the parent view of each item in the adapter's getView method. Android Studio suggests against this when using any AdapterView. It suggests overriding onItemLongClick instead.
Overriding onItemLongClick in the GridView. Evidently, that is also handled for you when in this selection mode.
Setting a custom onItemLongClickListener in the GridView.
While the hive works on this, I am going to try aborting the action mode's creation/blocking activation of prohibited items in the onItemCheckedStateChanged method of my AbsListView.MultiChoiceModeListener. Clearly I'm running low on ideas.

I have found a simple solution:
view.setOnLongClickListener(new View.OnLongClickListener() {
#Override
public boolean onLongClick(View v) {
return true;
}
});
or
view.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
return true;
}
});
where view is the item where you want to prevent a choice mode activation after a long click.

Cancel Touch Eventbutt

I am writing an very simple application with following scenario:
1) Screen A have 3 button to move on other screen's.
2) Now if I hold one button(say Button 1) and perform rapid click on other button then it launch multiple instance of other screen. Which I think should not be happened. How can prevent this.
3) and it's more weird. After move on other screen if I don't release Button 1 which was on Screen A then it still allow to perform click for rest of two button of screen A even I can see second screen.
Here it's clear launch second screen but still first screen button event working.
Any idea how can avoid such scenario.

How you are going to disable other buttons while having 1 enabled, that's an algorhytmic problem. You can try creating a boolean or control variable in your activity (and then pass the final reference of the activity to wherever you need it), or in a static context. But to answer the title of the question - you can "Cancel Touch Event" either by adding an OnTouchListener, or if you're extending class Button, you can override onTouchEvent(MotionEvent ev) method.
Using OnTouchListener will disable any previously defined touch-event behavior. You can call the actual click event from the inside by calling performClick method from your button.
//in order to use button inside OnTouchEvent, its reference must be final
//if it's not, create a new final reference to your button, like this:
final finalButton = button;
button.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouchEvent(MotionEvent ev) {
// ... additional code if necessary
if(canBeClicked) {
finalButton.performClick();
return true;
}
else return false;
}
}
Overriding onTouchEvent in a class extending Button should look something like this.
#Override
public boolean onTouchEvent(MotionEvent ev) {
// ... additional code if necessary
//here we don't really need to call performClick(), although API recommends it
//we just send the touch event to the super-class and let it handle the situation.
if(activity.canBeClicked) return super.onTouchEvent(ev);
else return false;
}

One solution that I found is to disable click listener in onPause() and enable it in onResume() . Can we have better support for this?

Automatic Android Click/Tap tracking

Is there a clever way to "do something" every time a user clicks or taps on the screen? I'd like to know which view they tapped on, and do it without having to replace all my standard views with custom views.
Basically, I want to add click tracking in my app to help with analytics. We already have page tracking (by using a shared superclass for every activity), but in some cases page tracking isn't enough and we actually want to track clicks.
How can I execute a function every time the user clicks on a View on the screen?

In each of your Activities, just add this at the end of onCreate (this is especially easy if all your Activities are subclasses of a custom Activity, because then you only need to write this once):
getWindow().getDecorView().findViewById(android.R.id.content).setOnTouchListener(new View.OnTouchListener() {
public boolean onTouch(View v, MotionEvent e) {
//handle your code here
return false;//don't absorb the touch.
}
});
Edit
The above code does not allow easy recognition of which Views are touched. The below code will. Note that this may break other onTouchListeners if the View in question already has registered an onTouch event. If not, this will work great. It uses the droidQuery library to select all views in the hierarchy and set uses code like above to handle touches without absorbing the event. The best place for this would be at the end of onCreate, in every Activity:
First, select the highest level of the architecture you want. If your layout's root view has an id, that would be the best thing:
$.with(this, R.id.root_id)
If not, either add one, or select the topmost view (above your layout). Note that for analytics this may provide some results you do not need:
$.with(this).selectAll()
Now, on the end of this selection, append the following:
.each(new Function() {
#Override
public void invoke($ d, Object... args) {
d.view(0).setOnTouchListener(new View.OnTouchListener() {
public boolean onTouch(View v, MotionEvent e) {
//do something with the clicked view, such as:
handleTouch(v, e);
return false;//don't absorb the touch.
}
})
}
});
Then have a new method:
private void handleTouch(View v, MotionEvent e) {
//handle the view touch.
}

Android: Is there any way to detect any user input?

on Android! I need to get user input (touch event, keyboard event). is there any way? In java code, It seems there is no way. What about native code?

In java code, It seems there is no way.
=> sorry, there is a way to do detect any action user made and play with application.
Some examples:
KeyboardView.OnKeyboardActionListener
Responding to Touch Events

for touch you can use
mView.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
//show dialog here
return false;
}
});

if your YourActivity implements OnTouchListener you can get the event and where the user touched on the screen:
public class YourActivity extends Activity implements OnTouchListener {
#Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
System.out.println("I touched: "+event.getX()+"-"+event.getY());
}
}

Actually I don't know what you exactly mean. Do you mean text input on an EditText or in General when something is touched?
If you mean text you can use TextWatcher
http://developer.android.com/reference/android/text/TextWatcher.html
If you mean on a View directly you can use OnTouchListener as mentioned above.

https://developer.android.com/reference/android/app/Activity.html#onUserInteraction()
Activity
public void onUserInteraction ()
Added in API level 3 Called whenever a key, touch, or trackball event
is dispatched to the activity. Implement this method if you wish to
know that the user has interacted with the device in some way while
your activity is running. This callback and onUserLeaveHint() are
intended to help activities manage status bar notifications
intelligently; specifically, for helping activities determine the
proper time to cancel a notfication.
All calls to your activity's onUserLeaveHint() callback will be
accompanied by calls to onUserInteraction(). This ensures that your
activity will be told of relevant user activity such as pulling down
the notification pane and touching an item there.
Note that this callback will be invoked for the touch down action that
begins a touch gesture, but may not be invoked for the touch-moved and
touch-up actions that follow.