按下后退按钮/折叠搜索字段时，Android搜索菜单项会消失 [英] Android Search menu item disappears when pressing back button/collapsing search field

问题描述

我正在使用Android SearchView在我的操作栏中设置搜索按钮。我在YouTube上关注了Google开发者的这个教程，并添加了一些基于我的调整自己的需要。但是，每当我退出单击按钮时出现的搜索字段时，搜索按钮就会消失！

I'm using android SearchView to have a search button in my action bar. I followed this tutorial from Google Developers on YouTube, and added a few tweaks based on my own needs. However, whenever I exit the search field that comes up when clicking the button, the search button disappears!

这是我的onCreateOptionsMenu和onOptionsItemSelected函数

Here is my onCreateOptionsMenu and onOptionsItemSelected functions

onCreateOptionsMenu：

onCreateOptionsMenu:

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);


    return true;
}

onOptionsItemSelected：

onOptionsItemSelected:

@Override
public boolean onOptionsItemSelected(final MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    switch (id) {
        case R.id.action_settings:
            // TODO: settings activity
            break;
        case R.id.action_logout:
            FirebaseAuth.getInstance().signOut();
            break;
        case R.id.action_search:
            // Initialize everything here, because it produces a NullPointerException if initialized in onCreateOptionsMenu
            SearchView searchView = (SearchView) MenuItemCompat.getActionView(item);
            SearchManager searchManager = (SearchManager)getSystemService(Context.SEARCH_SERVICE);
            ComponentName componentName = new ComponentName(this, SearchableActivity.class);
            searchView.setSearchableInfo(searchManager.getSearchableInfo(componentName));

            searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
                @Override
                public boolean onQueryTextSubmit(String query) {

                    return false;
                }

                @Override
                public boolean onQueryTextChange(String newText) {

                    return false;
                }
            });
            break;
    }

    return super.onOptionsItemSelected(item);
}

这是我的menu_main.xml布局文件

And here's my menu_main.xml layout file

<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
tools:context="com.magnus.inline.MainActivity">
<item
    android:id="@+id/action_search"
    android:icon="@drawable/ic_action_search"
    android:title="Search"
    app:actionViewClass="android.support.v7.widget.SearchView"
    app:showAsAction="ifRoom|collapseActionView"/>
<item
    android:id="@+id/action_settings"
    android:orderInCategory="100"
    android:title="@string/action_settings"
    app:showAsAction="never" />
<item
    android:id="@+id/action_logout"
    android:orderInCategory="200"
    android:title="@string/action_logout"
    app:showAsAction="never" />

和searchable.xml布局文件

And searchable.xml layout file

<?xml version="1.0" encoding="utf-8"?>
<searchable xmlns:android="http://schemas.android.com/apk/res/android"
    android:label="@string/app_name"
    android:hint="Search"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
</searchable>

图片

编辑：

我注意到搜索按钮消失的唯一时间是在搜索模式下按下选项按钮时（参见链接中的最后一张图像）。我有一种感觉，当显示选项菜单时，action_search以某种方式转换为选项菜单项，而不是操作栏项（？）。对于任何人来说，每当我尝试在onCreateOptionsMenu函数中调用searchview MenuItem的MenuItemCompat.getActionView（）时，我的应用程序就会崩溃并说它试图在空对象引用上执行它。

I noticed that the only time the search button disappears is when I've pressed the options button while in "search mode"(see the last image in link). I have a feeling that when the options menu is displayed, the "action_search" is somehow converted to a options menu item, instead of an action bar item (?). For anyone asking, whenever I try to call MenuItemCompat.getActionView() of a searchview MenuItem in the onCreateOptionsMenu function, my app just crashes and says that it tries to perform it on a null object reference.

这是我的activity_main.xml布局文件

Here's my activity_main.xml layout file

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 
xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/main_content"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context="com.magnus.inline.MainActivity">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/main_appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/main_toolbar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="?attr/colorPrimary"
            app:layout_scrollFlags="scroll|enterAlways"
            app:popupTheme="@style/AppTheme.PopupOverlay">

        </android.support.v7.widget.Toolbar>

        <android.support.design.widget.TabLayout
            android:id="@+id/tabs"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:theme="@style/AlertDialog.AppCompat.Light"
            android:background="@color/colorPrimaryDark" />

    </android.support.design.widget.AppBarLayout>

    <android.support.v4.view.ViewPager
        android:id="@+id/container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior" />

</android.support.design.widget.CoordinatorLayout>

推荐答案

而不是

app:showAsAction="ifRoom|collapseActionView"

更改为

app:showAsAction="always|collapseActionView

这篇关于按下后退按钮/折叠搜索字段时，Android搜索菜单项会消失的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！