Question

我试图获取存储在我的数组中的值（正确的答案），并将其与用户输入的答案进行比较。

这是我的数组：

String [][] multiArray = {{"4 + 5 = ", "9"},     
        {"20 * 3 - 1 = ","59"},
        {"99 - 9 = ","90"},
        {"50 / 2 + 18 = ","43"},
        {"9 * 8 = ","72"},
        {"4 + 20 - 20 = ","4"},
        {"75 / 5 = ","15"},
        {"99 - 1 * 3 = ","96"},
        {"75 + 25 = ","100"}};

如果答案正确或不正确，这就是解决问题的方法。如果不正确并且选中了提示选项。它应该比较用户输入的答案和数组中的正确答案。但是，如果数组是随机生成的，我将如何从数组中获取值？

public void hash_Clicked(View v){

    // Get the Answer from your EditText
    String answer =  display.getText().toString();
    setAnswer.setText(answer);


    // Using a for loop iterate on the base index
    for(int i = 0; i < multiArray.length ; i++)
    {      
        // if the answer is in position 1 of Array [i] 
        if(answer.equals(multiArray[i][1]))
        {
            // We have found the answer, Congratulate the User 
            displayAnswer.setTextColor(getResources().getColor(R.color.green));
            displayAnswer.setText("CORRECT");
            break;

         }else{
             // Tell them how bad they are since they can't solve simple equations!
             displayAnswer.setTextColor(getResources().getColor(R.color.red));
             displayAnswer.setText("INCORRECT");

             for (int count = 0; count<5; count++){
                 if(Prefs.getHints(this)){
                     if (answer > multiArray[1]){
                         setHints.setText("greater");
                     }
                 }

             }
         }


    }


}

这是生成随机表达式的代码：

public void onClick(View v) {
            Random ranGenerate = new Random ();
            int random = ranGenerate.nextInt(multiArray.length) ;
            // Fetch your random question
            String Rquestion = multiArray[random][0];
            displayExpression.setText(Rquestion);
            displayAnswer.setText("");
            setAnswer.setText("?");

        }

这是我需要帮助的地方：

if (answer > multiArray[i][1]){
                     setHints.setText("greater");
                 }

它说运营商＆gt;未定义参数类型java.lang.String，java.lang.String。那我怎么从数组中获取值？

Answer 1

首先，我认为你可能没有准确地描述你的问题。

正如你所说，

public void onClick(View v)似乎没有“生成”一个数组。它从现有multiArray[][]中选择一个随机问题。

话虽如此，您可以将其中生成的随机值存储为变量，以便您始终知道用户当前正在回答的问题...

修改

看到你的编辑后。

您正在使用字符串，必须将它们转换为数字类型（int，float，double等。）

// (Do some checkings before parsing, as the user may have inputted text...) if (Integer.parseInt(answer) > Integer.parseInt(multiArray[i][1])){ setHints.setText("greater"); }

编辑2：

您可以将当前问题的位置存储在Activity的变量中。每当您选择一个新的随机问题（在onClick(View v)中）时，请记住该变量中所选问题的位置。

然后，当您想要验证用户的答案时，您知道答案在multiArray[random][1]。解析用户答案的值以及从string到 int 等的正确答案。

class MyActivity extends Activity{ int random; // store the current question... String [][] multiArray = {{"4 + 5 = ", "9"}, {"20 * 3 - 1 = ","59"}, {"99 - 9 = ","90"}, {"50 / 2 + 18 = ","43"}, {"9 * 8 = ","72"}, {"4 + 20 - 20 = ","4"}, {"75 / 5 = ","15"}, {"99 - 1 * 3 = ","96"}, {"75 + 25 = ","100"}}; public void onClick(View v) { Random ranGenerate = new Random (); random = ranGenerate.nextInt(multiArray.length); // Fetch your random question String Rquestion = multiArray[random][0]; displayExpression.setText(Rquestion); displayAnswer.setText(""); setAnswer.setText("?"); } public void hash_Clicked(View v) { // 1 - The correct answer for current question is in multiarray[i][1] // 2 - Parse the strings to int/double/float // 3 - Do your checkings... // (careful as i might haven't been initialized) } }

Answer 2

if (answer > multiArray[i][1]){
    setHints.setText("greater");
}

您应该将两个字符串转换为整数以进行比较。

if (Integer.valueOf(answer) > Integer.valueOf(multiArray[i][1])) {
    setHints.setText("greater");
}

或Integer.parseInt()

你如何获取存储在多维数组（Android）中的值？

2 个答案: