android中屏蔽其它系统按钮的dialog

public class MyProgressDialog extends ProgressDialog {

	public MyProgressDialog(Context context) {
		super(context);
		this.getWindow().setType(
				WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG);
		// TYPE_KEYGUARD_DIALOG:disable any key,eg:back key,home key etc.
	}

	@Override
	public boolean onSearchRequested() {
		return false;
	}

}