android Launcher3 设置默认桌面应用

launcher3 的默认桌面应用是在 res/xml里
默认有4种样式
default_workspace_3x3.xml
default_workspace_4x4.xml
default_workspace_5x5.xml
default_workspace_5x6.xml

我们看看default_workspace_3x3.xml

<?xml version="1.0" encoding="utf-8"?>
<favorites xmlns:launcher="http://schemas.android.com/apk/res-auto/com.android.launcher3">

    <!-- Hotseat (We use the screen as the position of the item in the hotseat) -->
    <!-- Messaging, [All Apps], Dialer -->

    <resolve
        launcher:container="-101"
        launcher:screen="0"
        launcher:x="0"
        launcher:y="0" >
        <favorite launcher:uri="#Intent;action=android.intent.action.MAIN;category=android.intent.category.APP_MESSAGING;end" />
        <favorite launcher:uri="sms:" />
        <favorite launcher:uri="smsto:" />
        <favorite launcher:uri="mms:" />
        <favorite launcher:uri="mmsto:" />
    </resolve>

    <!-- All Apps -->

    <resolve
        launcher:container="-101"
        launcher:screen="2"
        launcher:x="2"
        launcher:y="0" >
        <favorite launcher:uri="#Intent;action=android.intent.action.DIAL;end" />
        <favorite launcher:uri="tel:123" />
        <favorite launcher:uri="#Intent;action=android.intent.action.CALL_BUTTON;end" />
    </resolve>

    <!-- Bottom row -->
    <resolve
        launcher:screen="0"
        launcher:x="0"
        launcher:y="-1" >
        <favorite launcher:uri="#Intent;action=android.intent.action.MAIN;category=android.intent.category.APP_EMAIL;end" />
        <favorite launcher:uri="mailto:" />
    </resolve>

    <resolve
        launcher:screen="0"
        launcher:x="1"
        launcher:y="-1" >
        <favorite launcher:uri="#Intent;action=android.intent.action.MAIN;category=android.intent.category.APP_GALLERY;end" />
        <favorite launcher:uri="#Intent;type=images/*;end" />
    </resolve>

    <resolve
        launcher:screen="0"
        launcher:x="2"
        launcher:y="-1" >
        <favorite launcher:uri="#Intent;action=android.intent.action.MAIN;category=android.intent.category.APP_MARKET;end" />
        <favorite launcher:uri="market://details?id=com.android.launcher" />
    </resolve>

    <!-- Second last row -->
    <resolve
        launcher:screen="0"
        launcher:x="0"
        launcher:y="-2" >
        <favorite launcher:uri="#Intent;action=android.intent.action.MAIN;category=android.intent.category.APP_BROWSER;end" />
        <favorite launcher:uri="http://www.example.com/" />
    </resolve>

    <resolve
        launcher:screen="0"
        launcher:x="2"
        launcher:y="-2" >
        <favorite launcher:uri="#Intent;action=android.media.action.STILL_IMAGE_CAMERA;end" />
        <favorite launcher:uri="#Intent;action=android.intent.action.CAMERA_BUTTON;end" />
    </resolve>

</favorites>

几个属性说明

    <resolve
        launcher:container="-101"//-101应该代表是hotseat，也就是说此应用将处于hotseat里
        launcher:screen="0"//应用所处屏幕
        launcher:x="0"//应用图标所处x位置
        launcher:y="0" >//应用图标所处y位置 
        <favorite    //标明这是快捷方式
        launcher:className="com.android.dialer.DialtactsActivity"//点击图标启动的类
        launcher:packageName="com.android.dialer" //应用包名  />
    </resolve>

其他说明
x,y,screen