nullPointerException當我嘗試從響應中將數據設置為文本視圖時，我JSON正在接受改造。我想將總銷售額、總費用和總購買值設置為 textviews：tv_total_purchase_today、tv_total_sale_today、tv_total_expense_today我應該在 setsaleInformations 方法中添加什么？這是我的代碼： API 響應public class DashboardResponse extends CommonResponse {@Expose@SerializedName("graph_data")private ArrayList<Graph> graph_data;@Expose@SerializedName("total_sale")private String total_sale;@Expose@SerializedName("total_purchase")private String total_purchase;@Expose@SerializedName("total_expense")private String total_expense;public ArrayList<Graph> getGraph_data() {    return graph_data;}public void setGraph_data(ArrayList<Graph> graph_data) {    this.graph_data = graph_data;}public String getTotal_sale() {    return total_sale;}public void setTotal_sale(String total_sale) {    this.total_sale = total_sale;}public String getTotal_purchase() {    return total_purchase;}public void setTotal_purchase(String total_purchase) {    this.total_purchase = total_purchase;}public String getTotal_expense() {    return total_expense;}public void setTotal_expense(String total_expense) {    this.total_expense = total_expense;}}