将导航视图状态传播到操作布局

Question

我正在使用 android 支持库创建导航抽屉。

<android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        android:background="@color/white"
        app:headerLayout="@layout/nav_header_landing"
        app:menu="@menu/activity_dashboard_drawer"
        app:theme="@style/MyActionButtonStyle"/>

我正在使用 actionLayout

创建自定义菜单项

<group android:checkableBehavior="single"
        android:id="@+id/gp_dashboard">
        <item
            android:id="@+id/nav_dashboard"
            app:actionLayout="@layout/layout_dashboard"
            android:icon="@mipmap/ic_dashboard"
            android:title=""/>
    </group>

这是布局"layout_dashboard"

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:duplicateParentState="true">

    <helpers.customViews.RobotoTextView
        android:id="@+id/dash_title"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="DASHBOARD"
        app:typeface="robotoMedium"
        android:textColor="@color/nav_header_state_list"
        android:textSize="14sp"/>

    <helpers.customViews.RobotoTextView
        android:id="@+id/dash_subtitle"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/dash_title"
        android:text="@string/dashboard_txt"
        app:typeface="robotoRegular"
        android:textColor="@color/nav_sub_header_state_list"
        android:textSize="12sp"/>

</RelativeLayout>

现在我想在选择菜单项时更改此布局的文本颜色。为此，我使用 @color/nav_header_state_list

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:color="@color/greeny_blue" android:state_checked="true"/>
    <item android:color="@color/greeny_blue" android:state_pressed="true" />
    <item android:color="@color/black"/>
</selector>

但是即使选择了菜单项，颜色也保持不变。 pressed state 有效，但 checked state 无效。请帮助我解决问题。

Answer 1

• 将 nav_header_state_list.xml
中的 state_checked 替换为 state_selected

您的 nav_header_state_list.xml 应如下所示：

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:color="@color/greeny_blue" android:state_pressed="true" />
    <item android:color="@color/greeny_blue" android:state_selected="true" />
    <item android:color="@color/black" />
</selector>

• 在 MainActivity.java
中声明 MenuItem 对象
• 将以下逻辑添加到 onNavigationItemSelected

您的 MainActivity.java 应该如下所示：

public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {

    MenuItem previousItem;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // ... some code
    }

    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();
        // ... some code

        if (previousItem != null) {
            View previousActionView = previousItem.getActionView();
            previousActionView.findViewById(R.id.dash_title).setSelected(false);
            previousActionView.findViewById(R.id.dash_subtitle).setSelected(false);
        }
        View actionView = item.getActionView();
        actionView.findViewById(R.id.dash_title).setSelected(true);
        actionView.findViewById(R.id.dash_subtitle).setSelected(true);
        previousItem = item;

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }
}