<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"

    android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context="wifi.app.wei.com.myapplication.MainActivity">

    <RelativeLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:padding="10dp"

        >

        <ImageView

            android:id="@+id/image"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:src="@mipmap/eye_close"

            android:layout_alignParentRight="true"

            android:layout_centerVertical="true"

            />

        <EditText

            android:id="@+id/pass_et"

            android:layout_toLeftOf="@id/image"

            android:layout_width="match_parent"

            android:layout_height="wrap_content"

            android:inputType="textPassword"

            />

    </RelativeLayout>

</RelativeLayout>

package wifi.app.wei.com.myapplication;

import android.os.Bundle;

import android.support.v7.app.AppCompatActivity;

import android.text.InputType;

import android.view.View;

import android.widget.EditText;

import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {

    private ImageView imageView ;

    private EditText editText ;

    boolean eyeOpen = false ;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main );

        imageView = (ImageView) findViewById( R.id.image) ;

        editText = (EditText) findViewById( R.id.pass_et);

        imageView.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                if ( eyeOpen ){

                    //密码 TYPE_CLASS_TEXT 和 TYPE_TEXT_VARIATION_PASSWORD 必须一起使用

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

                    imageView.setImageResource( R.mipmap.eye_close );

                    eyeOpen = false ;

                }else {

                    //明文

                    editText.setInputType( InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD );

                    imageView.setImageResource( R.mipmap.eye_open );

                    eyeOpen = true ;

                }

            }

        });

    }

}

package wifi.app.wei.com.myapplication;

import android.os.Bundle;

import android.support.v7.app.AppCompatActivity;

import android.text.method.HideReturnsTransformationMethod;

import android.text.method.PasswordTransformationMethod;

import android.view.View;

import android.widget.EditText;

import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {

    private ImageView imageView ;

    private EditText editText ;

    boolean eyeOpen = false ;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main );

        imageView = (ImageView) findViewById( R.id.image) ;

        editText = (EditText) findViewById( R.id.pass_et);

        imageView.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                if ( eyeOpen ){

                    //密码

                    editText.setTransformationMethod(PasswordTransformationMethod.getInstance());

                    imageView.setImageResource( R.mipmap.eye_close );

                    eyeOpen = false ;

                }else {

                    //明文

                    editText.setTransformationMethod(HideReturnsTransformationMethod.getInstance());

                    imageView.setImageResource( R.mipmap.eye_open );

                    eyeOpen = true ;

                }

            }

        });

    }

}