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)
    }

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)
    }

你可以使用app:passwordToggleEnabled="true"

下面是一个例子

<android.support.design.widget.TextInputLayout
        android:id="@+id/password"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:passwordToggleEnabled="true"
        android:textColorHint="@color/colorhint"
        android:textColor="@color/colortext">

you can use this

private fun showPasswordSwitch(checked: Boolean) {

    registerBinding.registerActivityEditTextPassword.also {
        // Password hide-show
        it.inputType =
            if (checked) TEXT_PASSWORD_SHOW else TEXT_PASSWORD_HIDE
           
    }
}
const val TEXT_PASSWORD_SHOW = InputType.TYPE_CLASS_TEXT or InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD

const val TEXT_PASSWORD_HIDE = InputType.TYPE_CLASS_TEXT or InputType.TYPE_TEXT_VARIATION_PASSWORD

使用复选框并相应地更改输入类型。

public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
    int start,end;
    Log.i("inside checkbox chnge",""+isChecked);
    if(!isChecked){
        start=passWordEditText.getSelectionStart();
        end=passWordEditText.getSelectionEnd();
        passWordEditText.setTransformationMethod(new PasswordTransformationMethod());;
        passWordEditText.setSelection(start,end);
    }else{
        start=passWordEditText.getSelectionStart();
        end=passWordEditText.getSelectionEnd();
        passWordEditText.setTransformationMethod(null);
        passWordEditText.setSelection(start,end);
    }
}

我使用了一个OnClickListener()，它与我想用作toogle的按钮相关联。

private EditText email_et, contraseña_et;
protected void onCreate(Bundle savedInstanceState) {
....
contraseña_et = (EditText) findViewById(R.id.contraseña_et);
....
vercontra_btn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            int inputType = contraseña_et.getInputType();
            if (inputType == 129){
                contraseña_et.setInputType(1);
            } else {
                contraseña_et.setInputType(129);
            }
            contraseña_et.setSelection(contraseña_et.getText().length());
        }
    });

阅读文档，int值似乎是不同的，所以我调试找到正确的值，它的工作棒极了，这是一个更容易一点的方式。

[顺便说一下，Contraseña是西班牙语的密码]