content: package amirz.shade.views;
  
  import android.content.Context;
  import android.util.AttributeSet;
  import android.util.TypedValue;
  import android.view.View;
  import android.widget.Checkable;
  import android.widget.LinearLayout;
  
  public class CheckableLinearLayout extends LinearLayout implements Checkable {
      private boolean mChecked;
      private float mDisabledAlpha;
  
      public CheckableLinearLayout(Context context, AttributeSet attrs) {
          super(context, attrs);
          TypedValue alpha = new TypedValue();
          context.getTheme().resolveAttribute(android.R.attr.disabledAlpha, alpha, true);
          mDisabledAlpha = alpha.getFloat();
      }
  
      @Override
      public void setEnabled(boolean enabled) {
          super.setEnabled(enabled);
          final int N = getChildCount();
          for (int i = 0; i < N; i++) {
              getChildAt(i).setAlpha(enabled ? 1 : mDisabledAlpha);
          }
      }
  
      @Override
      public void setChecked(boolean checked) {
          mChecked = checked;
          updateChecked();
      }
  
      @Override
      public boolean isChecked() {
          return mChecked;
      }
  
      @Override
      public void toggle() {
          setChecked(!mChecked);
      }
  
      private void updateChecked() {
          final int N = getChildCount();
          for (int i = 0; i < N; i++) {
              View child = getChildAt(i);
              if (child instanceof Checkable) {
                  ((Checkable) child).setChecked(mChecked);
              }
          }
      }
  }