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Simple RecyclerView example with filter option in Android

Hi Guys, Maybe you all are expert in terms of using RecyclerView in android. This blog is simple example for using filter option with RecyclerView adapter. As for now you will instantiate RecyclerView and set the adapter to RecyclerView as following way. RecyclerView list = (RecyclerView) findViewById(R.id.list); list.setLayoutManager(new LinearLayoutManager(this)); list.setHasFixedSize(true); ArrayList&ltNumber&gt numbers = new ArrayList&lt&gt(); String ONEs[] = {"ZERO", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE", "TEN"}; String TENs[] = {"ZERO", "TEN", "TWENTY", "THIRTY", "FOURTY", "FIFTY", "SIXTY", "SEVENTY", "EIGHTY", "NINETY", "HUNDRED"}; String HUNDREDS[] = {"ZERO", "HUNDRED", "TWO HUND...
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Using Button in Kotlin | Android

Though Kotlin has lot massive features to speedup the development time, here is the simple way of using Button in Android. 
import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import android.widget.Toast
import android.widget.Toast.LENGTH_LONG
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {

    private var count: Int = 0
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        myButton.setOnClickListener({
            count = count.inc()
            Toast.makeText(this, "Clicked Count " + count, LENGTH_LONG).show()
            myButton.setText("Click again")
        })
    }
}

Did you noticed, Here we used colon(:) instead of extends keyword, but here we used parentheses at end of the AppCompatActivity.
And we initialized count as Int var, where Int is one of the data type in Kotlin used to declare int variable from Java, and var defines count as variable, means, can be reinitialized at run time.
And we never declare myButton nor initialized, instead we directly accessed it from activity_main.
And inside setOnClickListener method, we didn't implement `OnClickListener` interface.

So, in simple accessing of button itself, we omitted near 10 lines of code. So imagine about full length project, near 40% of time is saved right?
So, If you think this is the right time to start with Kotlin, then start alongside with your current project. Yes, you can use Java and Kotlin in same project. If your current Activity is java, don't worry, you can create your next Activity in kotlin. Or you can convert your current Activity also to Kotlin and then continue learning Kotlin in same Activity.

Here is the full video tutorial

Interesting right?


If you are really interested in this code, then share this post with your friends.


Getting Started on Kotlin


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