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public string Foobar { get { return _foobar; } set { _foobar = value; } } private string _foobar = "xyz";

An exception can be caught and handled using the try...catch statement. (In fact try statements take other forms, as described in other examples about try...catch...finally and try-with-resources.) Try-catch with one catch block The most simple form looks like this: try { doSomething(); } ...

public class SampleAdapter extends RecyclerView.Adapter<SampleAdapter.ViewHolder> { private String[] mDataSet; private OnRVItemClickListener mListener; /** * Provide a reference to the type of views that you are using (custom ViewHolder) */ public static cla...

To use a NavigationView just add the dependency in the build.gradle file as described in the remarks section Then add the NavigationView in the layout <?xml version="1.0" encoding="utf-8"?> <android.support.v4.widget.DrawerLayout xmlns:android="http://schema...

The following example shows the basics of throwing an exception: public void checkNumber(int number) throws IllegalArgumentException { if (number < 0) { throw new IllegalArgumentException("Number must be positive: " + number); } } The exception is thrown on the 3...

This example illustrates sending a String with value as "Some data!" from OriginActivity to DestinationActivity. NOTE: This is the most straightforward way of sending data between two activities. See the example on using the starter pattern for a more robust implementation. OriginActivit...

When we create any View in layout, we can use the android:onClick attribute to reference a method in the associated activity or fragment to handle the click events. XML Layout <Button android:id="@+id/button" ... // onClick should reference the method in your activity or fra...

If your model has private methods, the databinding library still allows you to access them in your view without using the full name of the method. Data model public class Item { private String name; public String getName() { return name; } } Layout XML <?xml versi...

From the documentation: The exception that is thrown when an application attempts to perform a networking operation on its main thread. This is only thrown for applications targeting the Honeycomb SDK or higher. Applications targeting earlier SDK versions are allowed to do networking on their ma...

You can as well access other interface methods from within your default method. public interface Summable { int getA(); int getB(); default int calculateSum() { return getA() + getB(); } } public class Sum implements Summable { @Override public int get...

package com.example; import android.os.Bundle; import android.support.annotation.Nullable; import android.util.Log; import android.view.View; import android.view.ViewTreeObserver; public class ExampleActivity extends Activity { @Override protected void onCreate(@Nullable final ...

If you need to produce a JSON string with a value of null like this: { "name":null } Then you have to use the special constant JSONObject.NULL. Functioning example: jsonObject.put("name", JSONObject.NULL);

int i = 0; while (i < 100) { // condition gets checked BEFORE the loop body executes System.out.println(i); i++; } A while loop runs as long as the condition inside the parentheses is true. This is also called the "pre-test loop" structure because the conditional stateme...

The do...while loop differs from other loops in that it is guaranteed to execute at least once. It is also called the "post-test loop" structure because the conditional statement is performed after the main loop body. int i = 0; do { i++; System.out.println(i); } while (i &l...

public class MyActivity extends Activity { private static final String PREFS_FILE = "NameOfYourPrefrenceFile"; // PREFS_MODE defines which apps can access the file private static final int PREFS_MODE = Context.MODE_PRIVATE; // you can use live template "key"...

The String type provides two methods for converting strings between upper case and lower case: toUpperCase to convert all characters to upper case toLowerCase to convert all characters to lower case These methods both return the converted strings as new String instances: the original String o...

To check whether a particular String a is being contained in a String b or not, we can use the method String.contains() with the following syntax: b.contains(a); // Return true if a is contained in b, false otherwise The String.contains() method can be used to verify if a CharSequence can be fou...

Set up Android Studio Start by setting up Android Studio and then open it. Now, you're ready to make your first Android App! Note: this guide is based on Android Studio 2.2, but the process on other versions is mainly the same. Configure Your Project Basic Configuration You can start a new ...

Let's say you want to define an interface that allows publishing / consuming data to and from different types of channels (e.g. AMQP, JMS, etc), but you want to be able to switch out the implementation details ... Let's define a basic IO interface that can be re-used across multiple implementations...

A Pattern can be compiled with flags, if the regex is used as a literal String, use inline modifiers: Pattern pattern = Pattern.compile("foo.", Pattern.CASE_INSENSITIVE | Pattern.DOTALL); pattern.matcher("FOO\n").matches(); // Is true. /* Had the regex not been compiled case...