android - 我可以以编程方式打开带有动画的抽屉布局吗？

Question

我使用以下库创建了应​​用程序抽屉: http://developer.android.com/training/implementing-navigation/nav-drawer.html

我想在打开应用程序时显示带有动画的抽屉导航。 我该怎么做？

Answer 1

预绘制监听器，也就是安全通道

这是预绘制监听器示例。它会尽快开始动画，这可能有点太快了。您可能希望将此与第二个显示的可运行文件结合起来。我不会将两者结合起来，只会分开显示。

@Override
protected void onCreate(Bundle savedInstanceState) {
    ...
    // Building NavDrawer logic here. Just a method call would be best.
    ...

    ViewTreeObserver vto = drawer.getViewTreeObserver();
    if (vto != null) vto.addOnPreDrawListener(new ShouldShowListener(drawer));
}

private static class ShouldShowListener implements OnPreDrawListener {

    private final DrawerLayout drawerLayout;

    private ShouldShowListener(DrawerLayout drawerLayout) {
        this.drawerLayout= drawerLayout;
    }

    @Override
    public boolean onPreDraw() {
        if (view != null) {
            ViewTreeObserver vto = view.getViewTreeObserver();
            if (vto != null) {
                vto.removeOnPreDrawListener(this);
            }
        }

        drawerLayout.openDrawer(Gravity.LEFT);
        return true;
    }
}

PostDelay Runnable，又名生活危险

// Delay is in milliseconds
static final int DRAWER_DELAY = 200;

@Override
protected void onCreate(Bundle savedInstanceState) {
    ...
    // Building NavDrawer logic here. Just a method call would be best.
    ...
    new Handler().postDelayed(openDrawerRunnable(), DRAWER_DELAY);
}

private Runnable openDrawerRunnable() {
    return new Runnable() {

        @Override
        public void run() {
            drawerLayout.openDrawer(Gravity.LEFT);
        }
    }
}

警告

如果他们第一次在应用程序启动时轮换BOOM!阅读这篇博文了解更多信息http://corner.squareup.com/2013/12/android-main-thread-2.html .最好的办法是使用预绘制监听器或在 onPause 中删除您的可运行文件。