关于EditText密码框,切换显示或隐藏

直接上代码

private EditText edt;
	private CheckBox btn;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		edt = (EditText) findViewById(R.id.edt);
		btn = (CheckBox) findViewById(R.id.btn);
		btn.setOnCheckedChangeListener(new OnCheckedChangeListener() {
			@Override
			public void onCheckedChanged(CompoundButton buttonView,
					boolean isChecked) {
				// TODO Auto-generated method stub
				if (isChecked) {
					// 设置EditText文本为可见的
					edt.setTransformationMethod(HideReturnsTransformationMethod
							.getInstance());
				} else {
					// 设置EditText文本为隐藏的
					edt.setTransformationMethod(PasswordTransformationMethod
							.getInstance());
				}

				edt.postInvalidate();
				// 切换后将EditText光标置于末尾
				CharSequence charSequence = edt.getText();
				if (charSequence instanceof Spannable) {
					Spannable spanText = (Spannable) charSequence;
					Selection.setSelection(spanText, charSequence.length());
				}
			}
		});
	}