android - 使用FragmentTabHost在片段之间切换动画

我正在使用support.v4 FragmentTabHost，下面是它起作用的示例：

https://github.com/ClareZhang/Android-FragmentTabHost-demo

我想在片段之间放一张幻灯片动画，但我无法获得它，我已经使用FragmentTransactions尝试了一些操作，但它根本不起作用，而且我什至不确定这是否是正确的方法，因为FragmentTabHost照顾一切：

  mTabHost.setOnTabChangedListener(new OnTabChangeListener() {
@Override
public void onTabChanged(String tabId) {
    Log.v("onTabChanged", tabId);
        FragmentManager manager = getSupportFragmentManager();
        Fragment fr = manager.findFragmentByTag(tabId);
        if(fr != null){
            Log.v("Fragment", "TRANSACTION");
            FragmentTransaction ft  =   manager.beginTransaction();
            ft.setCustomAnimations(R.anim.left_slide_in, R.anim.left_slide_out);
            //ft.replace(R.id.realtabcontent, ...); //don't know how to get next fragment
            ft.commit();
        }
}

}）;

有什么简单的方法可以使用FragmentTabHost吗？我应该改用TabHost吗？

谢谢。

最佳答案

一年后，但我偶然发现了同样的问题。没错，FragmentTabHost可以处理所有事情，因此您不能从外部设置动画。

这是FragmentTabHost的原始代码，它会更改选项卡：

private FragmentTransaction doTabChanged(String tabId, FragmentTransaction ft) {
    TabInfo newTab = null;
    for (int i=0; i<mTabs.size(); i++) {
        TabInfo tab = mTabs.get(i);
        if (tab.tag.equals(tabId)) {
            newTab = tab;
        }
    }
    if (newTab == null) {
        throw new IllegalStateException("No tab known for tag " + tabId);
    }
    if (mLastTab != newTab) {
        if (ft == null) {
            ft = mFragmentManager.beginTransaction();
        }
        if (mLastTab != null) {
            if (mLastTab.fragment != null) {
                ft.detach(mLastTab.fragment);
            }
        }
        if (newTab != null) {
            if (newTab.fragment == null) {
                newTab.fragment = Fragment.instantiate(mContext,
                        newTab.clss.getName(), newTab.args);
                ft.add(mContainerId, newTab.fragment, newTab.tag);
            } else {
                ft.attach(newTab.fragment);
            }
        }

        mLastTab = newTab;
    }
    return ft;
}

我的解决方案是定义五个新成员，例如

private int mAnimationResToRightEnter = -1;
private int mAnimationResToRightExit = -1;
private int mAnimationResToLeftEnter = -1;
private int mAnimationResToLeftExit = -1;
private int mCurrentTabIndex;

和像这样的公共设置方法

public void setAnimation(int animResToRightEnter, int animResToRightExit, int animResToLeftEnter, int animResToLeftExit) {
    mAnimationResToRightEnter = animResToRightEnter;
    mAnimationResToRightExit = animResToRightExit;
    mAnimationResToLeftEnter = animResToLeftEnter;
    mAnimationResToLeftExit = animResToLeftExit;
}

然后，您可以在完成实际更改之前，只需在doTabChanged方法中设置动画：

private FragmentTransaction doTabChanged(String tabId, FragmentTransaction ft) {
    TabInfo newTab = null;
    for (int i=0; i<mTabs.size(); i++) {
        TabInfo tab = mTabs.get(i);
        if (tab.tag.equals(tabId)) {
            newTab = tab;
        }
    }
    if (newTab == null) {
        throw new IllegalStateException("No tab known for tag " + tabId);
    }
    if (mLastTab != newTab) {
        if (ft == null) {
            ft = mFragmentManager.beginTransaction();

            if (mAnimationResToRightEnter != -1 && mAnimationResToRightExit != -1 &&
                    mAnimationResToLeftEnter != -1 && mAnimationResToLeftExit != -1){
                // The user has set animation resources, let's set the right ones
                if (getCurrentTab() > m_CurrentTabIndex) {
                    // New tab is on the right, we want to exit and enter to the left
                    ft.setCustomAnimations(mAnimationResToLeftEnter, mAnimationResToLeftExit);
                } else {
                    // New tab is on the left, we want to exit and enter to the right
                    ft.setCustomAnimations(mAnimationResToRightEnter, mAnimationResToRightExit);
                }
                m_CurrentTabIndex = getCurrentTab();
            }
        }


        if (mLastTab != null) {
            if (mLastTab.fragment != null) {
                ft.detach(mLastTab.fragment);
            }
        }
        if (newTab != null) {
            if (newTab.fragment == null) {
                newTab.fragment = Fragment.instantiate(mContext,
                        newTab.clss.getName(), newTab.args);
                newTab.fragment.setAllowEnterTransitionOverlap(false);
                newTab.fragment.setAllowReturnTransitionOverlap(false);
                ft.add(mContainerId, newTab.fragment, newTab.tag);
            } else {
                ft.attach(newTab.fragment);
            }
        }

        mLastTab = newTab;
    }
    return ft;
}