密码明文密文切换

<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="?attr/actionBarSize">

    <EditText
        android:id="@+id/login_pwd"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:hint="请输入密码"
        android:paddingLeft="50dp"
        android:paddingRight="100dp"
        android:singleLine="true"
        android:password="true"/>

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:layout_marginLeft="10dp"
        android:padding="5dp"
        android:src="@drawable/iconfont_pwd" />

    <ImageView
        android:id="@+id/login_change"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:layout_marginRight="10dp"
        android:background="@drawable/display" />

    <ImageView
        android:id="@+id/login_change2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:layout_marginRight="10dp"
        android:background="@drawable/display_text"
        android:visibility="gone" />

    <ImageView
        android:id="@+id/login_pwd_clean"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:layout_alignParentRight="true"
        android:layout_marginRight="70dp"
        android:src="@drawable/search_clear_normal"
        android:visibility="invisible" />
</RelativeLayout> 

//监听密码是否输入
login_pwd.addTextChangedListener(new TextWatcher() {
    private CharSequence temp;

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        temp = s;
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {

    }

    @Override
    public void afterTextChanged(Editable s) {
        if (temp.length() > 0) {//限制长度
            login_pwd_clean.setVisibility(View.VISIBLE);
        } else {
            login_pwd_clean.setVisibility(View.INVISIBLE);
        }
    }
});

login_pwd_clean.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                login_pwd.setText("");
                login_pwd_clean.setVisibility(View.INVISIBLE);
            }
        });

//密码显示明文
login_change.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        LoginActivity.this.login_pwd.setTransformationMethod(HideReturnsTransformationMethod.getInstance());
        login_change.setVisibility(View.GONE);
        login_change2.setVisibility(View.VISIBLE);
    }
});

//密码显示密文
login_change2.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        LoginActivity.this.login_pwd.setTransformationMethod(PasswordTransformationMethod.getInstance());
        login_change2.setVisibility(View.GONE);
        login_change.setVisibility(View.VISIBLE);
    }
});