我所做的是

创建一个编辑文本视图和一个普通文本视图 通过使用约束布局使它们相互重叠(就像Facebook应用登录屏幕一样) 将onClickListener附加到普通文本视图，以便它相应地改变编辑文本视图的输入类型(可见/不可见)

你可以看看这个视频，了解更详细的步骤和解释https://youtu.be/md3eVaRzdIM

希望能有所帮助。

用复选框显示和隐藏密码Edit_Text

XML

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <EditText
        android:inputType="textPassword"
        android:id="@+id/edtPass"
        android:textSize="20dp"
        android:hint="password"
        android:padding="20dp"
        android:background="#efeaea"
        android:layout_width="match_parent"
        android:layout_margin="20dp"
        android:layout_height="wrap_content" />

    <CheckBox
        android:background="#ff4"
        android:layout_centerInParent="true"
        android:textSize="25dp"
        android:text="show password"
        android:layout_below="@id/edtPass"
        android:id="@+id/showPassword"
        android:layout_marginTop="20dp"
        android:layout_width="wrap_content"
        android:gravity="top|right"
        android:layout_height="wrap_content" />

</RelativeLayout>

java代码

package com.example.root.sql2;

import android.annotation.SuppressLint;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.AppCompatCheckBox;
import android.support.v7.widget.Toolbar;
import android.text.method.HideReturnsTransformationMethod;
import android.text.method.PasswordTransformationMethod;
import android.view.View;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.EditText;

public class password extends AppCompatActivity {


    EditText password;
    CheckBox show_hide_password;

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



    }//end onCreate



    public void show_hide_pass(){
        show_hide_password.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
                if (!b){
                    // hide password
                    password.setTransformationMethod(PasswordTransformationMethod.getInstance());

                }else{
                    // show password
                    password.setTransformationMethod(HideReturnsTransformationMethod.getInstance());
                }
            }
        });
    } // end show_hide_pass




    public void findViewById(){ //  find ids ui and
        password = (EditText) findViewById(R.id.edtPass);
        show_hide_password = (CheckBox) findViewById(R.id.showPassword);
    }//end findViewById



}// end class

只需在Xml文件中创建一个复选框

然后简单的用Java代码编写这个函数

checkbox = findViewById(R.id.checkbox);
        checkbox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener(){
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked){

                if (isChecked) {
                    password.setTransformationMethod(null);
                }
                else{
                    password.setTransformationMethod(new PasswordTransformationMethod());
                }
            }

        });

if (inputPassword.getTransformationMethod() == PasswordTransformationMethod.getInstance()) {
 //password is visible
                inputPassword.setTransformationMethod(HideReturnsTransformationMethod.getInstance());
            }
else if(inputPassword.getTransformationMethod() == HideReturnsTransformationMethod.getInstance()) {
 //password is hidden
                inputPassword.setTransformationMethod(PasswordTransformationMethod.getInstance());
            }

添加这个方法:

fun EditText.revertTransformation() {
    transformationMethod = when(transformationMethod) {
        is PasswordTransformationMethod -> SingleLineTransformationMethod.getInstance()
        else -> PasswordTransformationMethod.getInstance()
    }
}

调用它将在输入类型状态之间切换(您可以将Single-Line转换更改为您喜欢的)。使用的例子:

editText.revertTransformation()

TextInputLayout的更新代码:

   <androidx.cardview.widget.CardView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:layout_constraintBottom_toTopOf="@+id/lg_forget_password"
    app:layout_constraintTop_toBottomOf="@+id/lg_name"
    app:cardElevation="@dimen/dp20"
    android:layout_marginStart="@dimen/dp20"
    app:cardCornerRadius="@dimen/dp10"
    android:layout_marginEnd="@dimen/dp20"
    android:id="@+id/textField">

    <com.google.android.material.textfield.TextInputLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:backgroundTint="@android:color/transparent"
        app:boxStrokeWidth="0dp"
        app:boxStrokeWidthFocused="0dp"
        app:endIconMode="password_toggle"
        app:hintEnabled="false"
      >

        <com.google.android.material.textfield.TextInputEditText
            android:id="@+id/lg_password"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="@drawable/input_bg"
            android:drawableStart="@drawable/ic_baseline_lock_24"
            android:drawablePadding="@dimen/dp10"
            android:fontFamily="@font/roboto_flex"
            android:hint="@string/password"
            android:inputType="textPassword"
            android:padding="@dimen/dp15"
            android:singleLine="true" />

    </com.google.android.material.textfield.TextInputLayout>
</androidx.cardview.widget.CardView>

结果: