Full project with source code how to create a modal bottom sheet, by subclassing BottomSheetDialogFragment. Our sheet will have a custom layout and it will be able to communicate back to the underlying activity over an interface
dependency
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="vertical"
android:padding="16dp"
tools:context="tech.codingpoint.modalbottomsheetexample.MainActivity">
<Button
android:id="@+id/button_open_bottom_sheet"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Open Modal Bottom Sheet" />
<TextView
android:id="@+id/text_view_button_clicked"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button X clicked"
android:textSize="25sp" />
</LinearLayout>
bottom_sheet_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="vertical"
android:padding="16dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a BottomSheet"
android:textSize="25sp" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button 1" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button 2" />
</LinearLayout>
ExampleBottomSheetDialog.java
package tech.codingpoint.modalbottomsheetexample;
import android.content.Context;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.design.widget.BottomSheetDialogFragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
public class ExampleBottomSheetDialog extends BottomSheetDialogFragment {
private BottomSheetListener mListener;
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.bottom_sheet_layout, container, false);
Button button1 = v.findViewById(R.id.button1);
Button button2 = v.findViewById(R.id.button2);
button1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mListener.onButtonClicked("Button 1 clicked");
dismiss();
}
});
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mListener.onButtonClicked("Button 2 clicked");
dismiss();
}
});
return v;
}
public interface BottomSheetListener {
void onButtonClicked(String text);
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
try {
mListener = (BottomSheetListener) context;
} catch (ClassCastException e) {
throw new ClassCastException(context.toString()
+ " must implement BottomSheetListener");
}
}
}
MainActivity.java
package tech.codingpoint.modalbottomsheetexample;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity implements ExampleBottomSheetDialog.BottomSheetListener{
private TextView mTextView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTextView = findViewById(R.id.text_view_button_clicked);
Button buttonOpenBottomSheet = findViewById(R.id.button_open_bottom_sheet);
buttonOpenBottomSheet.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
ExampleBottomSheetDialog bottomSheet = new ExampleBottomSheetDialog();
bottomSheet.show(getSupportFragmentManager(), "exampleBottomSheet");
}
});
}
@Override
public void onButtonClicked(String text) {
mTextView.setText(text);
}
}