Java 如何使用按钮将文本打印到光标闪烁的编辑文本？

我在android studio中创建了两个EditText对象和10个编号为0到9的按钮对象。我希望我的按钮只为已选择的EditText对象输入相应的编号，即在光标闪烁的EditText中。 让我们假设EditText对象的id-s为input1和input2，以及一、二、三。。。按钮。

---

如果您能为我演示一个功能，即仅用于其中一个按钮的功能，我将不胜感激。

您可以设置两个

EditText

对象

onfocuschangelister

对于您的0-9按钮，您可以如下所示：

...
Button btn0, btn1, btn2, btn3, btn4, btn5, btn6, btn7, btn8, btn9;
EditText focusedView;
EditText etInput1, etInput2;
...

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // finding the EditTexts and Buttons with findViewById(), I am skipping that portion

    etInput1.setOnFocusChangeListener(focusListener);
    etInput2.setOnFocusChangeListener(focusListener);

    btn1.setOnClickListener(onClickListener);
    btn2.setOnClickListener(onClickListener);
    btn3.setOnClickListener(onClickListener);
    btn4.setOnClickListener(onClickListener);
    btn5.setOnClickListener(onClickListener);
    btn6.setOnClickListener(onClickListener);
    btn7.setOnClickListener(onClickListener);
    btn8.setOnClickListener(onClickListener);
    btn9.setOnClickListener(onClickListener);
    btn0.setOnClickListener(onClickListener);

}

public View.OnClickListener onClickListener = new View.OnClickListener(){
    public void onClick(View view){
        focusedView.append((Button)view).getText());
    }
}

private OnFocusChangeListener focusListener = new OnFocusChangeListener() {
    public void onFocusChange(View v, boolean hasFocus) {
        if (hasFocus){
             focusedView = (EditText)v;
        } else {
             focusedView  = null;
        }
    }
}

---

以下代码将很容易帮助您解决问题

public class Calc extends Activity implements View.OnClickListener{

    Button one, two, three, four, five, six, seven, eight, nine, zero, add, sub, mul, div, cancel, equal;
    EditText disp;
    int op1;
    int op2;
    String optr;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_home);

        one = (Button) findViewById(R.id.one);
        two = (Button) findViewById(R.id.two);
        three = (Button) findViewById(R.id.three);
        four = (Button) findViewById(R.id.four);
        five = (Button) findViewById(R.id.five);
        six = (Button) findViewById(R.id.six);
        seven = (Button) findViewById(R.id.seven);
        eight = (Button) findViewById(R.id.eight);
        nine = (Button) findViewById(R.id.nine);
        zero = (Button) findViewById(R.id.zero);
        add = (Button) findViewById(R.id.add);
        sub = (Button) findViewById(R.id.sub);
        mul = (Button) findViewById(R.id.mul);
        div = (Button) findViewById(R.id.div);
        cancel = (Button) findViewById(R.id.cancel);
        equal = (Button) findViewById(R.id.equal);

        disp = (EditText) findViewById(R.id.display);

        try{
            one.setOnClickListener(this);

            two.setOnClickListener(this);

            three.setOnClickListener(this);

            four.setOnClickListener(this);

            five.setOnClickListener(this);

            six.setOnClickListener(this);

            seven.setOnClickListener(this);

            eight.setOnClickListener(this);

            nine.setOnClickListener(this);

            zero.setOnClickListener(this);

            cancel.setOnClickListener(this);

            add.setOnClickListener(this);

            sub.setOnClickListener(this);

            mul.setOnClickListener(this);

            div.setOnClickListener(this);

            equal.setOnClickListener(this);
        }
        catch(Exception e){

        }
    }
    public void operation(){
        if(optr.equals("+")){
            op2 = Integer.parseInt(disp.getText().toString());
            disp.setText("");
            op1 = op1 + op2;
            disp.setText("Result : " + Integer.toString(op1));
        }
        else if(optr.equals("-")){
            op2 = Integer.parseInt(disp.getText().toString());
            disp.setText("");
            op1 = op1 - op2;
            disp.setText("Result : " + Integer.toString(op1));
        }
        else if(optr.equals("*")){
            op2 = Integer.parseInt(disp.getText().toString());
            disp.setText("");
            op1 = op1 * op2;
            disp.setText("Result : " + Integer.toString(op1));
        }
        else if(optr.equals("/")){
            op2 = Integer.parseInt(disp.getText().toString());
            disp.setText("");
            op1 = op1 / op2;
            disp.setText("Result : " + Integer.toString(op1));
        }
    }
    @Override
    public void onClick(View arg0) {
        Editable str =  disp.getText();
        switch(arg0.getId()){
            case R.id.one:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(two.getText());
                disp.setText(str);
            break;
            case R.id.two:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(two.getText());
                disp.setText(str);
            break;
            case R.id.three:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(three.getText());
                disp.setText(str);
            break;
            case R.id.four:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(four.getText());
                disp.setText(str);
            break;
            case R.id.five:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(five.getText());
                disp.setText(str);
            break;
            case R.id.six:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(six.getText());
                disp.setText(str);
            break;
            case R.id.seven:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(eight.getText());
                disp.setText(str);
            break;
            case R.id.eight:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(nine.getText());
                disp.setText(str);

            break;
            case R.id.nine:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(zero.getText());
                disp.setText(str);

            break;
            case R.id.cancel:
                op1 = 0;
                op2 = 0;
                disp.setText("");
                disp.setHint("Perform Operation :)");

            break;
            case R.id.add:
                optr = "+";
                if(op1 == 0){
                    op1 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                }
                else if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                else{
                    op2 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                    op1 = op1 + op2;
                    disp.setText("Result : " + Integer.toString(op1));
                }
            break;
            case R.id.sub:
                optr = "-";
                if(op1 == 0){
                    op1 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                }
                else if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                else{
                    op2 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                    op1 = op1 - op2;
                    disp.setText("Result : " + Integer.toString(op1));
                }
            break;
            case R.id.mul:
                optr = "*";
                if(op1 == 0){
                    op1 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                }
                else if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                else{
                    op2 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                    op1 = op1 * op2;
                    disp.setText("Result : " + Integer.toString(op1));
                }
            break;
            case R.id.div:
                optr = "/";
                if(op1 == 0){
                    op1 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                }
                else if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                else{
                    op2 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                    op1 = op1 / op2;
                    disp.setText("Result : " + Integer.toString(op1));
                }
            break;
            case R.id.equal:
                if(!optr.equals(null)){
                    if(op2 != 0){
                        if(optr.equals("+")){
                            disp.setText("");
                            /*op1 = op1 + op2;*/
                            disp.setText("Result : " + Integer.toString(op1));
                        }
                        else if(optr.equals("-")){
                            disp.setText("");/*
                            op1 = op1 - op2;*/
                            disp.setText("Result : " + Integer.toString(op1));
                        }
                        else if(optr.equals("*")){
                            disp.setText("");/*
                            op1 = op1 * op2;*/
                            disp.setText("Result : " + Integer.toString(op1));
                        }
                        else if(optr.equals("/")){
                            disp.setText("");/*
                            op1 = op1 / op2;*/
                            disp.setText("Result : " + Integer.toString(op1));
                        }
                    }
                    else{
                        operation();
                    }
                }
            break;
        }
    }
} e here

据我所知，你想在Android上制作一个计算器应用程序。如果是这样的话，那么给予的肯定会帮助你

public class Calc extends Activity implements View.OnClickListener{

    Button one, two, three, four, five, six, seven, eight, nine, zero, add, sub, mul, div, cancel, equal;
    EditText disp;
    int op1;
    int op2;
    String optr;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_home);

        one = (Button) findViewById(R.id.one);
        two = (Button) findViewById(R.id.two);
        three = (Button) findViewById(R.id.three);
        four = (Button) findViewById(R.id.four);
        five = (Button) findViewById(R.id.five);
        six = (Button) findViewById(R.id.six);
        seven = (Button) findViewById(R.id.seven);
        eight = (Button) findViewById(R.id.eight);
        nine = (Button) findViewById(R.id.nine);
        zero = (Button) findViewById(R.id.zero);
        add = (Button) findViewById(R.id.add);
        sub = (Button) findViewById(R.id.sub);
        mul = (Button) findViewById(R.id.mul);
        div = (Button) findViewById(R.id.div);
        cancel = (Button) findViewById(R.id.cancel);
        equal = (Button) findViewById(R.id.equal);

        disp = (EditText) findViewById(R.id.display);

        try{
            one.setOnClickListener(this);

            two.setOnClickListener(this);

            three.setOnClickListener(this);

            four.setOnClickListener(this);

            five.setOnClickListener(this);

            six.setOnClickListener(this);

            seven.setOnClickListener(this);

            eight.setOnClickListener(this);

            nine.setOnClickListener(this);

            zero.setOnClickListener(this);

            cancel.setOnClickListener(this);

            add.setOnClickListener(this);

            sub.setOnClickListener(this);

            mul.setOnClickListener(this);

            div.setOnClickListener(this);

            equal.setOnClickListener(this);
        }
        catch(Exception e){

        }
    }
    public void operation(){
        if(optr.equals("+")){
            op2 = Integer.parseInt(disp.getText().toString());
            disp.setText("");
            op1 = op1 + op2;
            disp.setText("Result : " + Integer.toString(op1));
        }
        else if(optr.equals("-")){
            op2 = Integer.parseInt(disp.getText().toString());
            disp.setText("");
            op1 = op1 - op2;
            disp.setText("Result : " + Integer.toString(op1));
        }
        else if(optr.equals("*")){
            op2 = Integer.parseInt(disp.getText().toString());
            disp.setText("");
            op1 = op1 * op2;
            disp.setText("Result : " + Integer.toString(op1));
        }
        else if(optr.equals("/")){
            op2 = Integer.parseInt(disp.getText().toString());
            disp.setText("");
            op1 = op1 / op2;
            disp.setText("Result : " + Integer.toString(op1));
        }
    }
    @Override
    public void onClick(View arg0) {
        Editable str =  disp.getText();
        switch(arg0.getId()){
            case R.id.one:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(two.getText());
                disp.setText(str);
            break;
            case R.id.two:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(two.getText());
                disp.setText(str);
            break;
            case R.id.three:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(three.getText());
                disp.setText(str);
            break;
            case R.id.four:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(four.getText());
                disp.setText(str);
            break;
            case R.id.five:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(five.getText());
                disp.setText(str);
            break;
            case R.id.six:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(six.getText());
                disp.setText(str);
            break;
            case R.id.seven:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(eight.getText());
                disp.setText(str);
            break;
            case R.id.eight:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(nine.getText());
                disp.setText(str);

            break;
            case R.id.nine:
                if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                str = str.append(zero.getText());
                disp.setText(str);

            break;
            case R.id.cancel:
                op1 = 0;
                op2 = 0;
                disp.setText("");
                disp.setHint("Perform Operation :)");

            break;
            case R.id.add:
                optr = "+";
                if(op1 == 0){
                    op1 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                }
                else if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                else{
                    op2 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                    op1 = op1 + op2;
                    disp.setText("Result : " + Integer.toString(op1));
                }
            break;
            case R.id.sub:
                optr = "-";
                if(op1 == 0){
                    op1 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                }
                else if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                else{
                    op2 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                    op1 = op1 - op2;
                    disp.setText("Result : " + Integer.toString(op1));
                }
            break;
            case R.id.mul:
                optr = "*";
                if(op1 == 0){
                    op1 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                }
                else if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                else{
                    op2 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                    op1 = op1 * op2;
                    disp.setText("Result : " + Integer.toString(op1));
                }
            break;
            case R.id.div:
                optr = "/";
                if(op1 == 0){
                    op1 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                }
                else if(op2 != 0){
                    op2 = 0;
                    disp.setText("");
                }
                else{
                    op2 = Integer.parseInt(disp.getText().toString());
                    disp.setText("");
                    op1 = op1 / op2;
                    disp.setText("Result : " + Integer.toString(op1));
                }
            break;
            case R.id.equal:
                if(!optr.equals(null)){
                    if(op2 != 0){
                        if(optr.equals("+")){
                            disp.setText("");
                            /*op1 = op1 + op2;*/
                            disp.setText("Result : " + Integer.toString(op1));
                        }
                        else if(optr.equals("-")){
                            disp.setText("");/*
                            op1 = op1 - op2;*/
                            disp.setText("Result : " + Integer.toString(op1));
                        }
                        else if(optr.equals("*")){
                            disp.setText("");/*
                            op1 = op1 * op2;*/
                            disp.setText("Result : " + Integer.toString(op1));
                        }
                        else if(optr.equals("/")){
                            disp.setText("");/*
                            op1 = op1 / op2;*/
                            disp.setText("Result : " + Integer.toString(op1));
                        }
                    }
                    else{
                        operation();
                    }
                }
            break;
        }
    }
} e here

---

对于您的代码，我希望通过按钮根据光标的位置在EditText对象etInput1或etInput2中输入数字。我不明白focusedView的用法，也不知道它将如何初始化。另外，尝试使用getText（）获取按钮的标题显示了一个错误。谢谢，我的应用程序正在按它应该的方式工作。我也了解focusedView的用法。：）@DiptangsuGoswami很高兴它成功了。。我收到了你的要求。。所以我建议这样。。快乐的编码！！