Java How to create a popup window (PopupWindow) in Android

To create a popup window in Android using Java, you can use the PopupWindow class.

Here is an example of how you can create a PopupWindow and display it in an Android activity:

import android.widget.PopupWindow;

public class MainActivity extends Activity {
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Create a PopupWindow
    PopupWindow popupWindow = new PopupWindow(this);

    // Set the content view of the PopupWindow
    popupWindow.setContentView(R.layout.popup_window);

    // Set the width and height of the PopupWindow
    popupWindow.setWidth(600);
    popupWindow.setHeight(400);

    // Show the PopupWindow
    popupWindow.showAtLocation(findViewById(R.id.root), Gravity.CENTER, 0, 0);
  }
}

This code creates a new PopupWindow object called popupWindow and sets its content view to a layout file called popup_window.xml. It then sets the width and height of the PopupWindow using the setWidth and setHeight methods.

Finally, the PopupWindow is displayed using the showAtLocation method, which takes a view to anchor the PopupWindow, and the gravity and x and y offset values. In this example, the PopupWindow is anchored to the root view of the activity and is displayed at the center of the screen.

You can also use the android.support.v7.widget.AppCompatPopupWindow class to create a PopupWindow if you are using the Android Support Library.

import android.support.v7.widget.AppCompatPopupWindow;

public class MainActivity extends Activity {
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Create a PopupWindow
    AppCompatPopupWindow popupWindow = new AppCompatPopupWindow(this);

    // Set the content view of the PopupWindow
    popupWindow.setContentView(R.layout.popup_window);

    // Set the width and height of the PopupWindow
    popupWindow.setWidth(600);
    popupWindow.setHeight(400);

    // Show the PopupWindow
    popupWindow.showAtLocation(findViewById(R.id.root), Gravity.CENTER, 0, 0);
  }
}

This code is similar to the previous example, but it uses the AppCompatPopupWindow class instead of the PopupWindow class. The AppCompatPopupWindow class is a backport of the PopupWindow class for use with the Android Support Library.