我也遇到过同样的问题，而且它很容易实现。

你所要做的就是在一个(com.google.android.material.textfield.TextInputLayout)和添加(app:passwordToggleEnabled="true")中包装你的EditText字段。

这将在EditText字段中显示眼睛，当您单击它时，密码将出现并在再次单击时消失。

<com.google.android.material.textfield.TextInputLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:textColorHint="#B9B8B8"
                app:passwordToggleEnabled="true">

                <EditText
                    android:id="@+id/register_password"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_marginLeft="24dp"
                    android:layout_marginRight="44dp"
                    android:backgroundTint="#BEBEBE"
                    android:hint="Password"
                    android:inputType="textPassword"
                    android:padding="16dp"
                    android:textSize="18sp" />
            </com.google.android.material.textfield.TextInputLayout>

我可以添加ShowPassword / HidePassword代码，只需几行，在一个块中独立:

protected void onCreate(Bundle savedInstanceState) {
    ...
    etPassword = (EditText)findViewById(R.id.password);
    etPassword.setTransformationMethod(new PasswordTransformationMethod()); // Hide password initially

    checkBoxShowPwd = (CheckBox)findViewById(R.id.checkBoxShowPwd);
    checkBoxShowPwd.setText(getString(R.string.label_show_password)); // Hide initially, but prompting "Show Password"
    checkBoxShowPwd.setOnCheckedChangeListener( new CompoundButton.OnCheckedChangeListener() {
        public void onCheckedChanged(CompoundButton arg0, boolean isChecked) {
            if (isChecked) {
                etPassword.setTransformationMethod(null); // Show password when box checked
                checkBoxShowPwd.setText(getString(R.string.label_hide_password)); // Prompting "Hide Password"
            } else {
                etPassword.setTransformationMethod(new PasswordTransformationMethod()); // Hide password when box not checked
                checkBoxShowPwd.setText(getString(R.string.label_show_password)); // Prompting "Show Password"
            }
        }
    } );
    ...

这是我的解决方案没有使用TextInputEditText和转换方法。

XML

<LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <TextView
            style="@style/FormLabel"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@string/username" />

        <EditText
            android:id="@+id/loginUsername"
            style="@style/EditTextStyle"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:drawableLeft="@drawable/ic_person_outline_black_24dp"
            android:drawableStart="@drawable/ic_person_outline_black_24dp"
            android:inputType="textEmailAddress"
            android:textColor="@color/black" />

        <TextView
            style="@style/FormLabel"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="20dp"
            android:text="@string/password" />

        <EditText
            android:id="@+id/loginPassword"
            style="@style/EditTextStyle"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:drawableEnd="@drawable/ic_visibility_off_black_24dp"
            android:drawableLeft="@drawable/ic_lock_outline_black_24dp"
            android:drawableRight="@drawable/ic_visibility_off_black_24dp"
            android:drawableStart="@drawable/ic_lock_outline_black_24dp"
            android:inputType="textPassword"
            android:textColor="@color/black" />
    </LinearLayout>

Java代码

boolean VISIBLE_PASSWORD = false;  //declare as global variable befor onCreate() 
loginPassword = (EditText)findViewById(R.id.loginPassword);
loginPassword.setOnTouchListener(new View.OnTouchListener() {
        public boolean onTouch(View v, MotionEvent event) {
            final int DRAWABLE_LEFT = 0;
            final int DRAWABLE_TOP = 1;
            final int DRAWABLE_RIGHT = 2;
            final int DRAWABLE_BOTTOM = 3;

            if (event.getAction() == MotionEvent.ACTION_UP) {
                if (event.getRawX() >= (loginPassword.getRight() - loginPassword.getCompoundDrawables()[DRAWABLE_RIGHT].getBounds().width())) {
                    // your action here
                    //Helper.toast(LoginActivity.this, "Toggle visibility");
                    if (VISIBLE_PASSWORD) {
                        VISIBLE_PASSWORD = false;
                        loginPassword.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);
                        loginPassword.setCompoundDrawablesWithIntrinsicBounds(R.drawable.ic_lock_outline_black_24dp, 0, R.drawable.ic_visibility_off_black_24dp, 0);
                    } else {
                        VISIBLE_PASSWORD = true;
                        loginPassword.setInputType(InputType.TYPE_CLASS_TEXT);
                        loginPassword.setCompoundDrawablesWithIntrinsicBounds(R.drawable.ic_lock_outline_black_24dp, 0, R.drawable.ic_visibility_black_24dp, 0);
                    }
                    return false;
                }
            }
            return false;
        }
    });

您必须询问当前文本是否已经显示了圆点，函数PasswordTransformationMethod.getInstance()允许您这样做。

这是我在kotlin中的函数:

        fun hideAndShowPassword(editText: EditText, indicator: ImageView) {

        if (editText.transformationMethod == PasswordTransformationMethod.getInstance()) {
            editText.transformationMethod = HideReturnsTransformationMethod.getInstance()
            indicator.setImageDrawable(
                ContextCompat.getDrawable(
                    editText.context,
                    R.drawable.eye
                )
            )
            indicator.imageTintList =
                ContextCompat.getColorStateList(editText.context, R.color.colorTintIcons)
        } else {
            editText.transformationMethod = PasswordTransformationMethod.getInstance()
            indicator.setImageDrawable(
                ContextCompat.getDrawable(
                    editText.context,
                    R.drawable.eye_off
                )
            )
            indicator.imageTintList =
                ContextCompat.getColorStateList(editText.context, R.color.colorTintIcons)
        }

        editText.setSelection(editText.text.length)
    }

显示:

editText.setInputType(InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD);

隐藏:

editText.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);

在这些之后，光标被重置，所以:

editText.setSelection(editText.length());

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()