Question

我有以下父容器：

public class ParentContainer extends Composite {
    // Contains a bunch of TextButtons (RedButton, GreenButton, etc.).
    private LayoutPanel buttonPanel;

    // When user clicks a TextButton inside the buttonPanel,
    // it changes the content of this contentPanel.
    private LayoutPanel contentPanel;
}

因此，当用户单击buttonPanel中的一个TextButtons时，contentPanel的内容会发生变化。我正在尝试使用Activities / Places框架让每个TextButton点击在历史记录中被记住。因此，如果用户分别单击“红色”，“绿色”和“蓝色”按钮，contentPanel将更改三次，然后他们可以单击后退/前进浏览器历史记录按钮并继续来回移动在历史中（和“重播”按钮一遍又一遍地点击等）。

我还有以下课程：

com.mywebapp
    MainModule.gwt.xml
com.mywebapp.client
    MainModule
com.mywebapp.client.places
    RedButtonPlace
    GreenButtonPlace
    BlueButtonPlace
    ... 1 place for all buttons
com.mywebapp.client.activities
    RedButtonActivity
    GreenButtonActivity
    BlueButtonActivity
    ... 1 activity for all buttons
com.mywebapp.client.ui
    ParentContainer
    RedButton
    GreenButton
    BlueButton
    BlackButton
    PurpleButton
    OrangeButton

我正在计划接线，以便：

PlaceController.goTo(new RedButtonPlace())最终路由到RedButtonActivity
PlaceController.goTo(new GreenButtonPlace())最终路由到GreenButtonActivity
等。（每个按钮的颜色都有一个位置和活动）

我坚持的是：如果我从PlaceController.goTo(new RedButtonPlace())点击处理程序中调用RedButton，我应该如何以及在何处指示RedButtonActivity更新contentPanel }？例如：

public class RedButton extends TextButton {
    // ... bunch of stuff, nevermind why I am extending TextButton
    // this is just to help me connect all the major dots of GWT!

    public RedButton() {
        this.addClickHandler(new ClickHandler() {
            public void onClick(ClickEvent event) {
                // If the RedButton is clicked, we want all the content in RedButtonActivity#RedButtonView
                // to go inside ParentContainer#contentPanel.
                PlaceController.goto(new RedButtonPlace());
            }
        });
    }
}

public class RedButtonActivity extends AbstractActivity {
    public interface RedButtonView extends IsWidget {
        // Whatever the RedButton expects to be able to display.
    }

    private RedButtonView view;

    @Override
    public void start(AcceptsOneWidget panel, EventBus eventBus) {
        // Probably injected via GIN.
        view = somehowInjectTheView();

        panel.setWidget(view);
    }
}

最后一行是关键点：panel.setWidget(view)。我们如何确保panel是ParentContainer#contentPanel？提前谢谢！

修改：根据一个答案建议，这是代码更新：

public class ParentContainer extends Composite {
    // All the stuff that's up above in the first parent container.

    public ParentContainer() {
        super();

        // Again, via GIN.
        ActivityManager redButtonActivityManager = getSomehow();
        redButtonActivityManager.setDisplay(contentPanel);
    }
}

如果这是正确的方法，那么我假设在调用start(AcceptsOneWidget panel, EventBus eventBus)方法时，redButtonActivityManager知道为panel参数注入正确的显示？

Answer 1

作为管理员初始化的一部分，您可以将ParentContainer#contentPanel传递给ActivityManager的{{3}}方法。

如何注入GWT Activity＃start与特定的Widget？

1 个答案: