Material Design——界面设计
1.Toolbar，标题栏
1】修改配置文件

<application
        android:name="org.litepal.LitePalApplication"
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.Android">
        
        <activity
            android:name=".MainActivity"
            android:label="Dummer">
         ......
        </activity>
    </application>

2】添加xml文件，目录res-meau-toolbar.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <item
        android:id="@+id/backup"
        android:icon="@drawable/ic_small"
        android:title="Backup"
        app:showAsAction="always" />

    <item
        android:id="@+id/deletes"
        android:icon="@drawable/ic_biggest"
        android:title="Delete"
        app:showAsAction="ifRoom" />

    <item
        android:id="@+id/setting"
        android:icon="@drawable/ic_car24"
        android:title="Settings"
        app:showAsAction="never" />
</menu>

3】修改activity，增加两个重写方法

 @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.toolbar, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
        switch (item.getItemId()) {
            case R.id.backup:
                Log.i(TAG, "you clicked Backup");
                break;
            case R.id.deletes:
                Log.i(TAG, "you clicked Delete");
                break;
            case R.id.setting:
                Log.i(TAG, "you clicked Settings");
                break;
            default:
                break;
        }
        return true;
    }

效果如下，Pass

2】