动态显示隐藏EditText内的密码

1.布局文件很简单，一个EditText，一个Button。

<EditText
    android:id="@+id/et_pwd"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:inputType="textPassword" />
<Button
    android:id="@+id/bn_show"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignRight="@id/et_pwd"
    android:layout_alignTop="@id/et_pwd"
    android:text="SHOW" />

2.实现功能

public class MainActivity extends Activity {
	private EditText etPwd;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		etPwd = (EditText) findViewById(R.id.et_pwd);
		findViewById(R.id.bn_show).setOnTouchListener(new OnTouchListener() {
			public boolean onTouch(View v, MotionEvent event) {
				switch (event.getAction()) {
				case MotionEvent.ACTION_DOWN:
					etPwd.setTransformationMethod(HideReturnsTransformationMethod
							.getInstance());
					break;
				default:
					etPwd.setTransformationMethod(PasswordTransformationMethod
							.getInstance());
					etPwd.postInvalidate();
					break;
				}
				return false;
			}
		});
	}
}