android中屏蔽其它系统旋钮的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;	}}