Android设置theme中的坑
16lz
2021-01-24
欢迎各位访问的博客,博客地址
配置项目主题的时候报了如下错误:
This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR
原因一
错误写法:
其中AppTheme使用的主题是AppCompat的主题,由于AppCompat主题下的windowActionBar和windowNoTitle的命名方式前都没有android字样,所以报错。
正确写法:
原因二
如果主题设置成有Actionbar的Theme并且没有配:
- "windowActionBar">false
- "windowNoTitle">true
也会出这样的错误。
看下源码:
在我们设置toolbar时候:((AppCompatActivity)getActivity()).setSupportActionBar(toolbar);
点进源码可以看到源码调用逻辑是:
public void setSupportActionBar(@Nullable Toolbar toolbar) { getDelegate().setSupportActionBar(toolbar); }
在往下追一步,出真相了:
public void setSupportActionBar(Toolbar toolbar) { if (!(mOriginalWindowCallback instanceof Activity)) { // Only Activities support custom Action Bars return; } //这里会去判有没有actionbar存在,如果有直接抛异常 final ActionBar ab = getSupportActionBar(); if (ab instanceof WindowDecorActionBar) { throw new IllegalStateException("This Activity already has an action bar supplied " + "by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set " + "windowActionBar to false in your theme to use a Toolbar instead."); } // If we reach here then we're setting a new action bar // First clear out the MenuInflater to make sure that it is valid for the new Action Bar mMenuInflater = null; // If we have an action bar currently, destroy it if (ab != null) { ab.onDestroy(); } if (toolbar != null) { final ToolbarActionBar tbab = new ToolbarActionBar(toolbar, ((Activity) mContext).getTitle(), mAppCompatWindowCallback); mActionBar = tbab; mWindow.setCallback(tbab.getWrappedWindowCallback()); } else { mActionBar = null; // Re-set the original window callback since we may have already set a Toolbar wrapper mWindow.setCallback(mAppCompatWindowCallback); } invalidateOptionsMenu(); }
主要在这里:
//这里会去判有没有actionbar存在,如果有直接抛异常final ActionBar ab = getSupportActionBar(); if (ab instanceof WindowDecorActionBar) { throw new IllegalStateException("This Activity already has an action bar supplied " + "by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set " + "windowActionBar to false in your theme to use a Toolbar instead."); }
好了,结束。
更多相关文章
- 【Android】下载Android源码的简明步骤
- android源码下载与编译过程记录
- Ubuntu 12.04(64位)下载并编译 Android(安卓)4.1 源码[只有2条命令
- android Error:Execution failed for task ':app:transformClass
- 使用RecyclerView加载不出数据的原因可能有:
- Android:Textview 通过代码设置 Drawable
- android控件之spinner (下拉列表)
- android4.2 屏蔽home键
- Android(安卓)debug 问题集合