java - 如何从单独类的对话框中返回值

我想创建一个在屏幕上显示带有2个按钮的对话框的函数，如果用户按OK，则返回1，如果用户按Cancel，则返回0。

public class CDlg {

static int ShowConfirm(String caption, String msg, Context context) {
    int rez;
    AlertDialog.Builder delAllDialog = new AlertDialog.Builder(context);
    delAllDialog.setTitle(caption);

    TextView dialogTxt_id = new TextView(context);
    LayoutParams dialogTxt_idLayoutParams = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
    dialogTxt_id.setLayoutParams(dialogTxt_idLayoutParams);
    dialogTxt_id.setText(msg);
    LinearLayout layout = new LinearLayout(context);
    layout.setOrientation(LinearLayout.VERTICAL);
    layout.addView(dialogTxt_id);
    delAllDialog.setView(layout);

    delAllDialog.setPositiveButton("OK", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface arg0, int arg1) {
            rez = 1;
        }
    });

    delAllDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface arg0, int arg1) {
            rez = 0;
        }
    });

    delAllDialog.show();
    return rez;
}

}

我现在确定自己做对了，因为我不知道如何将结果从较差的类传递给外部的类。有错误讯息

Cannot refer to a non-final variable rez inside an inner class defined in a different method

因此，我想使用该功能，如下所示：

if (CDlg.ShowConfirm("User confirmation","Delete?",this)==1){
        ...
}

最佳答案

你不能那样做。 ShowConfirm仅可以显示对话框。当用户单击“确定”或“取消”按钮时，才可以执行所需的操作：

public class CDlg {
    void ShowConfirm(String caption, String msg) {
        AlertDialog.Builder delAllDialog = new AlertDialog.Builder(this);
        delAllDialog.setTitle(caption);

        TextView dialogTxt_id = new TextView(this);
        LayoutParams dialogTxt_idLayoutParams = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
        dialogTxt_id.setLayoutParams(dialogTxt_idLayoutParams);
        dialogTxt_id.setText(msg);
        LinearLayout layout = new LinearLayout(this);
        layout.setOrientation(LinearLayout.VERTICAL);
        layout.addView(dialogTxt_id);
        delAllDialog.setView(layout);

        delAllDialog.setPositiveButton("OK", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface arg0, int arg1) {
                handleButtonClick(1);
            }
        });

        delAllDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface arg0, int arg1) {
                handleButtonClick(2);
            }
        });

        delAllDialog.show();
    }

    void handleButtonClick(int rez) {
        switch(rez) {
            case 1: ..... break;
            case 2: ..... break;
            .....
        }
    }
}

在这里，if (CDlg.ShowConfirm("User confirmation","Delete?",this)==1)语句在Android中是无用的，因为ShowConfirm不会等到用户按下按钮。

相反，只需调用ShowConfirm("User confirmation","Delete?");在onClick中实现适当的代码即可。