Add new UnreadMessageButton class

briar-android/src/main/java/org/briarproject/briar/android/view/UnreadMessageButton.java

@@ -0,0 +1,76 @@
+package org.briarproject.briar.android.view;
+
+import android.content.Context;
+import android.content.res.TypedArray;
+import android.support.annotation.Nullable;
+import android.support.annotation.UiThread;
+import android.support.design.widget.FloatingActionButton;
+import android.util.AttributeSet;
+import android.view.LayoutInflater;
+import android.widget.FrameLayout;
+import android.widget.TextView;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.briar.R;
+
+@UiThread
+@NotNullByDefault
+public class UnreadMessageButton extends FrameLayout {
+
+	private final static int UP = 0, DOWN = 1;
+
+	private final FloatingActionButton fab;
+	private final TextView unread;
+
+	public UnreadMessageButton(Context context) {
+		this(context, null);
+	}
+
+	public UnreadMessageButton(Context context, @Nullable AttributeSet attrs) {
+		this(context, attrs, 0);
+	}
+
+	public UnreadMessageButton(Context context, @Nullable AttributeSet attrs,
+			int defStyleAttr) {
+		super(context, attrs, defStyleAttr);
+
+		LayoutInflater inflater = (LayoutInflater) context
+				.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
+		inflater
+				.inflate(R.layout.unread_message_button, this, true);
+
+		fab = (FloatingActionButton) findViewById(R.id.fab);
+		unread = (TextView) findViewById(R.id.unreadCountView);
+
+		TypedArray attributes = context.obtainStyledAttributes(attrs,
+				R.styleable.UnreadMessageButton);
+		int direction = attributes
+				.getInteger(R.styleable.UnreadMessageButton_direction, DOWN);
+		setDirection(direction);
+		attributes.recycle();
+
+		setUnreadCount(0);
+	}
+
+	private void setDirection(int direction) {
+		if (direction == UP) {
+			fab.setImageResource(R.drawable.chevron_up_white);
+		} else if (direction == DOWN) {
+			fab.setImageResource(R.drawable.chevron_down_white);
+		} else {
+			throw new IllegalArgumentException();
+		}
+	}
+
+	public void setUnreadCount(int count) {
+		if (count == 0) {
+			unread.setVisibility(INVISIBLE);
+			fab.hide();
+		} else {
+			unread.setVisibility(VISIBLE);
+			unread.setText(String.valueOf(count));
+			if (!fab.isShown()) fab.show();
+		}
+	}
+
+}