Android 使用EditText的连续OTP输入

这里有4个EditText用于输入数字密码。我希望它是这样的，若第一个EditText由1个数字填充，那个么焦点应该转到下一个EditText，并且应该以相反的方式工作。所以用户可以从最左边继续输入密码，也可以从最右边以同样的方式删除密码

有人能建议什么是最好的继续进行的方法吗

如果您熟悉RxJava，那么这可能是满足您需求的最简单方法。 下面是Kotlin代码的示例

同样的方法，你也可以写反向。长度为零时，将焦点放在上一个编辑文本上。

您可以使用该库

或者，您可以使用addTextChangedListener添加一个TextWatcher，每当此EditTextView的文本发生变化时，就会调用该TextWatcher，然后您可以调用View.requestFocus对下一个EditText进行聚焦，以聚焦它

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    >

    <EditText
        android:id="@+id/otpET1"
        android:layout_width="30dp"
        android:layout_height="30dp"
        android:inputType="number"
        android:maxLength="1"
        android:gravity="center"
        android:textSize="20sp"/>

    <EditText
        android:id="@+id/otpET2"
        android:layout_width="30dp"
        android:layout_height="30dp"
        android:inputType="number"
        android:maxLength="1"
        android:gravity="center"
        android:textSize="20sp"/>
    <EditText
        android:id="@+id/otpET3"
        android:layout_width="30dp"
        android:layout_height="30dp"
        android:inputType="number"
        android:maxLength="1"
        android:gravity="center"
        android:textSize="20sp"/>

    <EditText
        android:id="@+id/otpET4"
        android:layout_width="30dp"
        android:layout_height="30dp"
        android:inputType="number"
        android:maxLength="1"
        android:gravity="center"
        android:textSize="20sp"/>
    <EditText
        android:id="@+id/otpET5"
        android:layout_width="30dp"
        android:layout_height="30dp"
        android:inputType="number"
        android:maxLength="1"
        android:gravity="center"
        android:textSize="20sp"/>
    <EditText
        android:id="@+id/otpET6"
        android:layout_width="30dp"
        android:layout_height="30dp"
        android:inputType="number"
        android:gravity="center"
        android:maxLength="1"
        android:textSize="20sp"/>
</LinearLayout>

最后,

String code = Helpers.rS(otpETs[0]) + Helpers.rS(otpETs[1]) + 
Helpers.rS(otpETs[2]) + Helpers.rS(otpETs[3]) + Helpers.rS(otpETs[4]) 
+ Helpers.rS(otpETs[5]);

或者只需使用一个简单的for/while循环。

在Kotlin中，您可以使用以下命令：

---

仅使用addTextChangedListener无法完成此操作。您可能需要同时设置onKeyListener。以下是您的代码：

//6 EditTexts are otpEt[0], otpEt[1],...otpEt[5]
private EditText[] otpEt = new EditText[6];
    otpEt[0] = (EditText) findViewById(R.id.otpEt1);
    otpEt[1] = (EditText) findViewById(R.id.otpEt2);
    otpEt[2] = (EditText) findViewById(R.id.otpEt3);
    otpEt[3] = (EditText) findViewById(R.id.otpEt4);
    otpEt[4] = (EditText) findViewById(R.id.otpEt5);
    otpEt[5] = (EditText) findViewById(R.id.otpEt6);

setOtpEditTextHandler();

private void setOtpEditTextHandler () { //This is the function to be called
    for (int i = 0;i < 6;i++) { //Its designed for 6 digit OTP
        final int iVal = i;

        otpEt[iVal].addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

            }

            @Override
            public void afterTextChanged(Editable s) {
                if(iVal == 5 && !otpEt[iVal].getText().toString().isEmpty()) {
                    otpEt[iVal].clearFocus(); //Clears focus when you have entered the last digit of the OTP.
                } else if (!otpEt[iVal].getText().toString().isEmpty()) {
                    otpEt[iVal+1].requestFocus(); //focuses on the next edittext after a digit is entered.
                }
            }
        });

        otpEt[iVal].setOnKeyListener(new View.OnKeyListener() {
            @Override
            public boolean onKey(View v, int keyCode, KeyEvent event) {
                if (event.getAction() != KeyEvent.ACTION_DOWN) {
                    return false; //Dont get confused by this, it is because onKeyListener is called twice and this condition is to avoid it.
                }
                if(keyCode == KeyEvent.KEYCODE_DEL && 
otpEt[iVal].getText().toString().isEmpty() && iVal != 0) {
//this condition is to handel the delete input by users.
                    otpEt[iVal-1].setText("");//Deletes the digit of OTP
                    otpEt[iVal-1].requestFocus();//and sets the focus on previous digit
                }
                return false;
            }
        });
    }
}

如果您觉得这段代码很难，只需将其粘贴到您的项目中，然后尝试重新安排。你会很容易得到它的

public class Helpers {

    public static String rS(EditText editText) {
        return editText.getText().toString().trim();
    }
}

String code = Helpers.rS(otpETs[0]) + Helpers.rS(otpETs[1]) + 
Helpers.rS(otpETs[2]) + Helpers.rS(otpETs[3]) + Helpers.rS(otpETs[4]) 
+ Helpers.rS(otpETs[5]);

txtOTP_1.addTextChangedListener(object : TextWatcher {
     override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
         if (txtOTP_1.text.toString().length == 1) {
             txtOTP_1.clearFocus()
             txtOTP_2.requestFocus()
             txtOTP_2.setCursorVisible(true)
         }
     }

     override fun beforeTextChanged(s: CharSequence, start: Int, count: Int, after: Int) {

     }

     override fun afterTextChanged(s: Editable) {
         if (txtOTP_1.text.toString().length == 0) {
             txtOTP_1.requestFocus()
         }
     }
 })


 txtOTP_2.addTextChangedListener(object : TextWatcher {
     override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
         if (txtOTP_2.text.toString().length == 1) {           
             txtOTP_2.clearFocus()
             txtOTP_3.requestFocus()
             txtOTP_3.setCursorVisible(true)

         }
     }

     override fun beforeTextChanged(s: CharSequence, start: Int, count: Int, after: Int) {
     }

     override fun afterTextChanged(s: Editable) {
         if (txtOTP_2.text.toString().length == 0) {               
             txtOTP_2.requestFocus()
         }

     }
 })

 txtOTP_3.addTextChangedListener(object : TextWatcher {
     override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
         if (txtOTP_3.text.toString().length == 1) {                
             txtOTP_3.clearFocus()
             txtOTP_4.requestFocus()
             txtOTP_4.setCursorVisible(true)               
         }
     }

     override fun beforeTextChanged(s: CharSequence, start: Int, count: Int, after: Int) {
     }

     override fun afterTextChanged(s: Editable) {
         if (txtOTP_3.text.toString().length == 0) {             
             txtOTP_3.requestFocus()
         }

     }
 })

 txtOTP_4.addTextChangedListener(object : TextWatcher {
     override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
         if (txtOTP_4.text.toString().length == 1) {                
             txtOTP_4.clearFocus()
             txtOTP_5.requestFocus()
             txtOTP_5.setCursorVisible(true)
         }
     }

     override fun beforeTextChanged(s: CharSequence, start: Int, count: Int, after: Int) {
     }

     override fun afterTextChanged(s: Editable) {
         if (txtOTP_4.text.toString().length == 0) {
             txtOTP_4.requestFocus()
         }           
     }
 })


 txtOTP_5.addTextChangedListener(object : TextWatcher {
     override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
         if (txtOTP_5.text.toString().length == 1) {              
             txtOTP_5.requestFocus()
             txtOTP_5.setCursorVisible(true)

         }
     }
  })

//6 EditTexts are otpEt[0], otpEt[1],...otpEt[5]
private EditText[] otpEt = new EditText[6];
    otpEt[0] = (EditText) findViewById(R.id.otpEt1);
    otpEt[1] = (EditText) findViewById(R.id.otpEt2);
    otpEt[2] = (EditText) findViewById(R.id.otpEt3);
    otpEt[3] = (EditText) findViewById(R.id.otpEt4);
    otpEt[4] = (EditText) findViewById(R.id.otpEt5);
    otpEt[5] = (EditText) findViewById(R.id.otpEt6);

setOtpEditTextHandler();

private void setOtpEditTextHandler () { //This is the function to be called
    for (int i = 0;i < 6;i++) { //Its designed for 6 digit OTP
        final int iVal = i;

        otpEt[iVal].addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

            }

            @Override
            public void afterTextChanged(Editable s) {
                if(iVal == 5 && !otpEt[iVal].getText().toString().isEmpty()) {
                    otpEt[iVal].clearFocus(); //Clears focus when you have entered the last digit of the OTP.
                } else if (!otpEt[iVal].getText().toString().isEmpty()) {
                    otpEt[iVal+1].requestFocus(); //focuses on the next edittext after a digit is entered.
                }
            }
        });

        otpEt[iVal].setOnKeyListener(new View.OnKeyListener() {
            @Override
            public boolean onKey(View v, int keyCode, KeyEvent event) {
                if (event.getAction() != KeyEvent.ACTION_DOWN) {
                    return false; //Dont get confused by this, it is because onKeyListener is called twice and this condition is to avoid it.
                }
                if(keyCode == KeyEvent.KEYCODE_DEL && 
otpEt[iVal].getText().toString().isEmpty() && iVal != 0) {
//this condition is to handel the delete input by users.
                    otpEt[iVal-1].setText("");//Deletes the digit of OTP
                    otpEt[iVal-1].requestFocus();//and sets the focus on previous digit
                }
                return false;
            }
        });
    }
}