How to set click listener to LinearLayout using data binding

Question

I am currently trying to set a click listener to a LinearLayout view in the .xml layout file using data binding.

I have managed to get it to work well on other views like a Button or TextView, but for some reason it is not working with a LinearLayout.

This is the bare bones of my attempts and I still cannot get it to work:

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="72dp"
    android:clickable="true"
    android:focusable="true"
    android:onClick="@{action::linearLayoutClicked}"
    android:orientation="vertical">
</LinearLayout>

Where linearLayoutClicked is my method defined in the action class:

public void linearLayoutClicked(View view) {
    // specific logic
}

I have also tried with child views and those child views with clickable and focusable set to false as well as duplicateParentState set to true and false.

That action is exactly the same action that is being used on other views which is working correctly.

Is this a bug or am I doing this incorrectly? Why is this not working for LinearLayout but works without any problems for other views?

Ignore data binding for the moment. If you remove the `android:onClick()` attribute, and you call `setOnClickListener()` on your `LinearLayout`, do you get the results that you want? — CommonsWare, Mar 30 '18 at 18:15
@CommonsWare Yes, in-code click listener works correctly on the `LinearLayout`. — Shadow, Mar 30 '18 at 18:18
Hmmm... you might consider looking at the code that gets generated by data binding and see what's in there when you have your `android:onClick` attribute in place. What you have should be OK, though the combination that you're trying (event handler registered via data binding on a non-interactive `View`) may not have been thoroughly tested. — CommonsWare, Mar 30 '18 at 18:21
use `android:onClick="linearLayoutClicked"` instead of `android:onClick="@{action::linearLayoutClicked}"` i tried and its working — akhilesh0707, Mar 30 '18 at 18:22
The generated bindings file shows the same structure set for the other working views, there isn't anything different other than the view type. — Shadow, Mar 30 '18 at 18:22
Try adding android:clickable=true to the LinearLayout. A wild guess, have not tried myself — , Mar 30 '18 at 18:23
@Thomas Read my sample, it is already using that attribute with that value. — Shadow, Mar 30 '18 at 18:24
@akhilesh0707 I doubt what you said, I just tried and the app crashes due to `Could not find method linearLayoutClicked` — Shadow, Mar 30 '18 at 18:26
@Shadow you defined `linearLayoutClicked` method inside your activity right? because i tried and its working — akhilesh0707, Mar 30 '18 at 18:28
@akhilesh0707 No, it is a fragment, not an Activity. Now it makes sense why it works for you and not for me. However, thanks to this rubber banding I managed to find what the problem was and fix it. It finally works after 3 days of trying! — Shadow, Mar 30 '18 at 18:30

score 21 · Answer 1 · edited Dec 01 '21 at 09:09

You can handle any view click event like below:

Create interface for handle click event like below:

interface OnClickHandlerInterface {
    void onClick(View view)
}

Implement that click listener in action class as shown below:

class MainActivity implements OnClickHanderInterface{
    @Override
    void OnClick(View view){
    }
}

Now bind this interface in XML file:

<data>
    <variable
        name="clickHandler"
        type=".OnClickHandlerInterface" />
</data>

Now register this interface in action class with use of binding object:
```
mActivityMainBinding.clickHandler = this
```

Now set onClick on any which you want to set click listener. For you it's LinearLayout:

<LinearLayout
    android:id="@+id/linearLayout"
    android:layout_width="match_parent"
    android:layout_height="72dp"
    android:clickable="true"
    android:focusable="true"
    android:onClick="@{(v)-> clickHandler.onClick(v)}"
    android:orientation="vertical">
</LinearLayout>

Now handle click when your linearLayout clicked you can get click on interface which is implemented in action class:

@Override
void OnClick(View view){
    switch(view.getId()){
    case R.id.linearLayout:
        // Handler click and do some actions
        break;
    }
}

As mentioned above you can get layout click by data binding.

score 3 · Accepted Answer · edited Dec 01 '21 at 09:19

So everything was set up correctly and the generated bindings file shows the click listener being set up correctly, but for some very odd reason half the bindings were working and the newer ones weren't. By newer ones meaning the LinearLayout and all the attempts around it.

What solved the problem was a simple cache invalidation and respective restart and voila, the click listener is working perfectly on the LinearLayout. Just remember to set it clickable and focusable and any child views set as not clickable so they don't consume the event before the parent.

Khemraj Sharma · Answer 3 · 2019-03-10T16:18:11.670

0

If Invalidate Cache does not work.

then Rebuild project from Build>Rebuild. Fix errors if any then Rebuild again.

edited Mar 10 '19 at 16:18

answered Aug 07 '18 at 08:04

Khemraj Sharma

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How to set click listener to LinearLayout using data binding

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