Question

我正在编程计算器，我目前差不多完成了;编程等于按钮。我希望能够测试是否单击了equals按钮并在此之前单击了另一个按钮，执行一些代码这就是我所拥有的：

package rechee.cool;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class HelloAndroidActivity extends Activity 
{
    /** Called when the activity is first created. */

    double counter1=0;
    double counter2=0;
    String theOperator;
    //Just have two buttons so far, I'm going to have like 10 more

    public EditText display;        

    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        // Associate the button variable with the xml reference

        display = (EditText) findViewById(R.id.editText1);}

        //When button is clicked, display the text. How do I do this for the rest of my variables?

        public void onClick(View v) 
        {
            switch(v.getId())
            {
                case R.id.bOne:
                display.append("1");
                    break;
                case R.id.bTwo:                     
                    display.append("2");
                    break;
                case R.id.bThree:
                    display.append("3");
                    break;
                case R.id.bFour:
                    display.append("4");
                    break;
                case R.id.bFive:
                    display.append("5");
                    break;
                case R.id.bSix:
                    display.append("6");
                    break;

                case R.id.bSeven:
                    display.append("7");
                    break;
                case R.id.bEight:
                    display.append("8");
                    break;
                case R.id.bNine:
                    display.append("9");
                    break;
                case R.id.bZero:
                    display.append("0");
                    break;
                case R.id.bPoint:
                    display.append(".");
                    break;
                case R.id.bClear:
                    display.setText("");
                    break;
                case R.id.bAdd:
                    // to get string of EditText 
                    String display1= display.getText().toString();
                    double displayValue= Double.parseDouble(display1);
                    //to test if display1 is double
                    counter1+= displayValue;
                    String theOperator = "+";
                    break;
                case R.id.bEqual:
                    if (R.id.bAdd=true){

                    }           
            }                       
        } 
    }
}

Answer 1

使用堆栈数据结构存储按下的每个按钮。当您检测到有效序列（即操作数运算符操作数相等，1 + 1 =）时，执行它并从堆栈中删除值。

测试按钮的值是否为真。 Android项目

1 个答案: