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Android: Handle Onclick Listerner in included layout [duplicate]

I have two java class and two layout for both the class.
Each layout is having one button in it.
Both classes are extending Activity.
Now in first layout I used include tag like this
<include
android:id="#+id/clicked"
layout="#layout/activity_main" />
I can now see two buttons but the second button is not working.

First You have to declare and initialise the include view and then decalre and initialise both buttons using view.findViewById() method as follows:
View includeView = (View)findViewById(R.id.clicked);
Button button1 = (Button)includeView.findViewById(R.id.button1ID); //decalre button like this
Button button2 = (Button)includeView.findViewById(R.id.button2ID);
And then set their onClickListeners
button1.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
//code whatever you want to do here
}
});
button2.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
//code whatever you want to do here
}
});
** EDIT **
Fixed the typo. Should be includeView on the findViewById.
Good explanation though!

When to set onClickListener with View and when with Button?

I have just started to learn Android Application Development from thenewboston.com tutorials.
I had a confusion with setting the onClickListener event handler. When setting it for a button in the main activity, they used the Button class.
redButton.setOnClickListener(
new Button.onClickListener(){
public void onClick(View v){
// Do Something
}
}
);
But when setting it for a fragment they used the view class.
redButton.setOnClickListener(
new View.onClickListener(){
public void onClick(View v){
// Do Something
}
}
);
What is the difference between the two ? And when to use them ?
Please Help !!

In Button also, you can use View also as you are using in fragment.
Actually both works identically.It is just the way you want to go for better solution than other.
For more details you could refer:
setOnclickListener vs OnClickListener vs View.OnClickListener
Difference between specifying the view.onclicklistener and just having onclicklistener

Button.onClickListener() could only be used for Button. But View.onClickListener() could be used for any view. So what is the right way of doing it?
Well, what you have currently done is called 'setting an anonymous listener`. That's bad. More info here: https://softwareengineering.stackexchange.com/a/110113
The best way to do is let your Activity or Fragment implement the View.onClickListener() and the override the onClick() method.

Button is derived class of View, so onClickListener of Button is overridden from onClickListener for View.
And there is no difference between two implementations.
In the documentation for button example uses view.onClickListener
final Button button = (Button) findViewById(R.id.button_id);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// Perform action on click
}
});
so that seems the recomanded way.

setting onclicklistener for several buttons [duplicate]

I'm new to android development. I've a doubt.
I know that you can add a button and initialize it like
Button b1=(Button) findViewById(R.id.button1);
and I can also give a unction name in the XML file.
android:onClick="click_event"
My doubt is, which is the best and efficient way?
like it says that its better to use #string resource instead of a hard-coded one.

I think you are confused. The examples you give are two different things.
Adding a Button
This line
Button b1=(Button) findViewById(R.id.button1);
doesn't add a Button. It declares and initializes an instance of Button which refers to a Button in your currently inflated xml which has an id of button1
So in your xml you would have somewhere
<Button
android:id="#+id/button1"
<!-- other properties -->
/>
You can add a Button programmatically with
Button bt1 = new Button(this);
// give it properties
But it is generally easier to do in xml because here you have to programmatically give it parameters, properties, and add it to an inflated layout
OnClick
As far as the onClick() it depends on what you feel is the easiest and best in your situation. I like to declare it in the xml like that often but you can do it several ways. Using this method you just have to be sure that you have a function like this that is public and takes only one parameter and that parameter must be a View
public void clickEvent(View v)
{
// code here
}
I also changed the name so your xml would be like
<Button
android:id="#+id/button1"
<!-- other properties -->
android:onClick="clickEvent"/>
You also can set onClick() in your Java with something like
Button b1=(Button) findViewById(R.id.button1);
b1.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v)
{
// code here
}
});
or
Button b1=(Button) findViewById(R.id.button1);
b1.setOnClickListener(this);
#Override
public void onClick(View v)
{
// code here
}
Note that the last way you will need to add implements OnClickListener in your Activity declaration
public class MyActivity extends Activity implements OnClickListener
{
You can also create your own click Listener by changing it to something like
b1.setOnClickListener(myBtnClick);
then create an instance of it with something like
public OnClickListener myBtnClick = new OnClickListener()
{
#Override
public void onClick(View v)
{
// click code here
}
};
You can use this for multiple Buttons and switch on the id or check the View param to know which Button was clicked or create separate Listeners for different Buttons.

Android: Make several buttons use the same onClickListener object [duplicate]

I'm new to android development. I've a doubt.
I know that you can add a button and initialize it like
Button b1=(Button) findViewById(R.id.button1);
and I can also give a unction name in the XML file.
android:onClick="click_event"
My doubt is, which is the best and efficient way?
like it says that its better to use #string resource instead of a hard-coded one.

I think you are confused. The examples you give are two different things.
Adding a Button
This line
Button b1=(Button) findViewById(R.id.button1);
doesn't add a Button. It declares and initializes an instance of Button which refers to a Button in your currently inflated xml which has an id of button1
So in your xml you would have somewhere
<Button
android:id="#+id/button1"
<!-- other properties -->
/>
You can add a Button programmatically with
Button bt1 = new Button(this);
// give it properties
But it is generally easier to do in xml because here you have to programmatically give it parameters, properties, and add it to an inflated layout
OnClick
As far as the onClick() it depends on what you feel is the easiest and best in your situation. I like to declare it in the xml like that often but you can do it several ways. Using this method you just have to be sure that you have a function like this that is public and takes only one parameter and that parameter must be a View
public void clickEvent(View v)
{
// code here
}
I also changed the name so your xml would be like
<Button
android:id="#+id/button1"
<!-- other properties -->
android:onClick="clickEvent"/>
You also can set onClick() in your Java with something like
Button b1=(Button) findViewById(R.id.button1);
b1.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v)
{
// code here
}
});
or
Button b1=(Button) findViewById(R.id.button1);
b1.setOnClickListener(this);
#Override
public void onClick(View v)
{
// code here
}
Note that the last way you will need to add implements OnClickListener in your Activity declaration
public class MyActivity extends Activity implements OnClickListener
{
You can also create your own click Listener by changing it to something like
b1.setOnClickListener(myBtnClick);
then create an instance of it with something like
public OnClickListener myBtnClick = new OnClickListener()
{
#Override
public void onClick(View v)
{
// click code here
}
};
You can use this for multiple Buttons and switch on the id or check the View param to know which Button was clicked or create separate Listeners for different Buttons.

How can set onClickListner fo buttons..?

I am new to android. I want to set OnclickListner for different buttons which are located in different xml layouts.

You can also use a definition like that directly in the XML-file:
<Button android:onClick="myClickHandler" />
After that you can create the method "myClickHandler" in your Code like that:
class MyActivity extends Activity {
public void myClickHandler(View target) {
// Do stuff
}
}

Something like this:
final Button button = (Button) findViewById(R.id.button_id);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// Perform action on click
}
});
Then all you need to do is reference the different buttons by their different ids set in the XML