# 瀏覽器差異

> ## 瀏覽器差異 \#

## ChangeEvent

* GWT 2.6
* GXT 3.1

`CheckBox` 的 `ChangeEvent`（GWT）發生時，`CheckBox.getValue()` 會有差異：

* Chrome（35）：變更之前的值
* FireFox（30）：變更之後的值，個人認為這個比較合理  \[遠目]

搭配 `ValueChangeEvent`，例如

```java
    @UiHandler("fooCheckBox")
    void handleChange(ChangeEvent ce) {
        Window.alert("change event");
    }

    @UiHandler("fooCheckBox")
    void handleValueChange(ValueChangeEvent<Boolean> vce) {
        Window.alert("value change event");
    }
```

* Chrome（35）：先出現 change event、後出現 value change event
* FireFox（30）：順序顛倒

最後，以開發上來說，應該只要管 `ValueChangeEvent` 就好， `ValueChangeEvent.getValue()` 的回傳值，至少目前測起來 Chrome 跟 FireFox 是一致的， 所以這個瀏覽器差異不知道什麼時候才會被炸到 \[遠目]。


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