原始碼：http://download.csdn.net/detail/lm_zp/9522549

XMl

<LinearLayout 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" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#ffff33" >

        <EditText
            android:id="@+id/password"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:background="@null"
            android:drawableLeft="@drawable/ic_tip_pwd"
            android:hint="請輸入密碼"
            android:singleLine="true" />

        <CheckBox
            android:id="@+id/checkbox"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:background="@drawable/mycheckbox"
            android:button="@null" />
    </LinearLayout>

</LinearLayout>
 

package com.example.mypassword;

import android.os.Bundle;
import android.app.Activity;
import android.text.Selection;
import android.text.Spannable;
import android.text.method.HideReturnsTransformationMethod;
import android.text.method.PasswordTransformationMethod;
import android.view.Menu;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.EditText;

public class MainActivity extends Activity {

	private EditText editText;
	private CheckBox checkBox;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		editText = (EditText) findViewById(R.id.password);
		checkBox = (CheckBox) findViewById(R.id.checkbox);
		 // 設定第一次輸入密碼未不可見狀態
		editText.setTransformationMethod(PasswordTransformationMethod
                .getInstance());
		checkBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
			
			@Override
			public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
				// TODO Auto-generated method stub
				if(isChecked){
					  // 設定EditText文字為可見的
					editText
                            .setTransformationMethod(HideReturnsTransformationMethod
                                    .getInstance());
				}else{
					editText.setTransformationMethod(PasswordTransformationMethod
			                .getInstance());
				}
				// 切換後將EditText游標置於末尾
                CharSequence charSequence = editText.getText();
                if (charSequence instanceof Spannable) {
                    Spannable spanText = (Spannable) charSequence;
                    Selection.setSelection(spanText,
                            charSequence.length());
                }
			}
		});
		
		
		
	}



}