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());
            }

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)
    }

一个很好的解决方案。设置一个按钮，然后使用下面的代码:

public void showPassword(View v)
{

    TextView showHideBtnText = (TextView) findViewById(R.id.textView1);

    if(showHideBtnText.getText().toString().equals("Show Password")){
        password.setTransformationMethod(null);
        showHideBtnText.setText("Hide");
    } else{
        password.setTransformationMethod(new PasswordTransformationMethod());
        showHideBtnText.setText("Show Password");
    }


}

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());
                }
            }

        });

你试过setTransformationMethod吗?它继承自TextView，并希望TransformationMethod作为参数。

你可以在这里找到更多关于TransformationMethods的信息。

它还有一些很酷的功能，比如字符替换。