我正在尝试实现动画搜索视图(带有简单的扩展/折叠动画),但是该论坛中的所有答案均不起作用.

android:id="@+id/action_search"

android:orderInCategory="100"

android:title="@string/action_search"

app:actionViewClass="android.support.v7.widget.SearchView"

android:icon="@drawable/ic_search_white_48px"

app:showAsAction="always"/>

我做了什么

@Override

public boolean onCreateOptionsMenu(Menu menu) {

// Inflate the menu; this adds items to the action bar if it is present.

getMenuInflater().inflate(R.menu.main, menu);

SearchView searchView = (SearchView) menu.findItem(R.id.action_search).getActionView();

//Get the ID for the search bar LinearLayout

int searchBarId = searchView.getContext().getResources().getIdentifier("android:id/search_bar", null, null);

//Get the search bar Linearlayout

LinearLayout searchBar = (LinearLayout)

searchView.findViewById(searchBarId);

//Give the Linearlayout a transition animation.

searchBar.setLayoutTransition(new LayoutTransition());

return true;

}

所有错误：

E/AndroidRuntime: FATAL EXCEPTION: main

Process: com.daveslab.wideview, PID: 2459

java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.LinearLayout.setLayoutTransition(android.animation.LayoutTransition)' on a null object reference

at com.daveslab.wideview.MainActivity.onCreateOptionsMenu(MainActivity.java:69)

at android.app.Activity.onCreatePanelMenu(Activity.java:2846)

at android.support.v4.app.FragmentActivity.onCreatePanelMenu(FragmentActivity.java:360)

at android.support.v7.view.WindowCallbackWrapper.onCreatePanelMenu(WindowCallbackWrapper.java:88)

at android.support.v7.app.AppCompatDelegateImplBase$AppCompatWindowCallbackBase.onCreatePanelMenu(AppCompatDelegateImplBase.java:331)

at android.support.v7.view.WindowCallbackWrapper.onCreatePanelMenu(WindowCallbackWrapper.java:88)

at android.support.v7.app.ToolbarActionBar.populateOptionsMenu(ToolbarActionBar.java:454)

at android.support.v7.app.ToolbarActionBar$1.run(ToolbarActionBar.java:61)

at android.os.Handler.handleCallback(Handler.java:739)

at android.os.Handler.dispatchMessage(Handler.java:95)

at android.os.Looper.loop(Looper.java:148)

at android.app.ActivityThread.main(ActivityThread.java:5417)

at java.lang.reflect.Method.invoke(Native Method)

at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)

at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

values.xml中的错误(所有图标均在项目中具有正确的名称)：

Error:(1605, 21) No resource found that matches the given name: attr 'searchBackIcon'.

错误：(1602,21)找不到与给定名称匹配的资源：attr’searchBackground’.

错误：(1604,21)找不到与给定名称匹配的资源：attr’searchCloseIcon’.

错误：(1606,21)找不到与给定名称匹配的资源：attr’searchSuggestionBackground’.

错误：(1603,21)找不到与给定名称匹配的资源：attr’searchVoiceIcon’.

错误：(1605,21)找不到与给定名称匹配的资源：attr’searchBackIcon’.

错误：(1602,21)找不到与给定名称匹配的资源：attr’searchBackground’.

错误：(1604,21)找不到与给定名称匹配的资源：attr’searchCloseIcon’.

错误：(1606,21)找不到与给定名称匹配的资源：attr’searchSuggestionBackground’.

错误：(1603,21)找不到与给定名称匹配的资源：attr’searchVoiceIcon’.

错误：任务’：app：processDebugResources’的执行失败.

com.android.ide.common.process.ProcessException：无法执行aapt.