android 1.6 launcher研究之修改worksapce上的屏数

 参考： http://blog.csdn.net/fzh0803/archive/2011/03/26/6279995.aspx
http://gqdy365.iteye.com/blog/897638
http://www.cnblogs.com/playing/archive/2011/03/26/1996209.html

android1.6的版本有3个屏 需要把它改为5个屏 需要修改的地方 如下

1、Launcher.java

static final int SCREEN_COUNT = 5;
static final int DEFAULT_SCREN = 2;

static final int SCREEN_COUNT = 5;
static final int DEFAULT_SCREN = 2;

2、launcher.xml

<com.lp.launcher.Workspace
        android:id="@+id/workspace"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"

        launcher:defaultScreen="2">//从0开始

        <include android:id="@+id/cell1" layout="@layout/workspace_screen" />
        <include android:id="@+id/cell2" layout="@layout/workspace_screen" />
        <include android:id="@+id/cell3" layout="@layout/workspace_screen" />
        <include android:id="@+id/cell4" layout="@layout/workspace_screen" />
        <include android:id="@+id/cell5" layout="@layout/workspace_screen" />

</com.lp.launcher.Workspace>

<com.lp.launcher.Workspace
        android:id="@+id/workspace"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"

        launcher:defaultScreen="2">//从0开始

        <include android:id="@+id/cell1" layout="@layout/workspace_screen" />
        <include android:id="@+id/cell2" layout="@layout/workspace_screen" />
        <include android:id="@+id/cell3" layout="@layout/workspace_screen" />
        <include android:id="@+id/cell4" layout="@layout/workspace_screen" />
        <include android:id="@+id/cell5" layout="@layout/workspace_screen" />

</com.lp.launcher.Workspace>

defaultScreen 修改为2 然后 加两个<include />

然后 修改默认显示的屏

3、Workspace.java

修改构造方法里面的

mDefaultScreen = a.getInt(R.styleable.Workspace_defaultScreen, 2);//从0开始

mDefaultScreen = a.getInt(R.styleable.Workspace_defaultScreen, 2);//从0开始

这时 基本上已经可以显示5个屏幕了 默认的屏也是第三个屏了 但是进去后 默认显示的屏什么也没有 我们需要把组建都挪到默认屏上去

4、default_workspace.xml

修改所有的 launcher:screen 为 2 

launcher:screen="2"

launcher:screen="2"

修改完这个后 如果你不是make到源码 而是以app的方式安装到手机上的话 就必须先卸载原有的这个程序 然后在部署

但是 这里有一个问题 我们上次修改的标记 也需要修改

5、home_arrows_left.xml home_arrows_right.xml

<level-list xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:maxLevel="0" android:drawable="@android:color/transparent" />
    <item android:maxLevel="1" android:drawable="@drawable/home_arrows_left_1" />
    <item android:maxLevel="2" android:drawable="@drawable/home_arrows_left_2" />
    <item android:maxLevel="3" android:drawable="@drawable/home_arrows_left_3" />
    <item android:maxLevel="4" android:drawable="@drawable/home_arrows_left_4" />

</level-list>

<level-list xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:maxLevel="0" android:drawable="@drawable/home_arrows_right_4" />
    <item android:maxLevel="1" android:drawable="@drawable/home_arrows_right_3" />
    <item android:maxLevel="2" android:drawable="@drawable/home_arrows_right_2" />
    <item android:maxLevel="3" android:drawable="@drawable/home_arrows_right_1" />
    <item android:maxLevel="4" android:drawable="@android:color/transparent" />

</level-list>

<level-list xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:maxLevel="0" android:drawable="@android:color/transparent" />
    <item android:maxLevel="1" android:drawable="@drawable/home_arrows_left_1" />
    <item android:maxLevel="2" android:drawable="@drawable/home_arrows_left_2" />
    <item android:maxLevel="3" android:drawable="@drawable/home_arrows_left_3" />
    <item android:maxLevel="4" android:drawable="@drawable/home_arrows_left_4" />
    
</level-list>

<level-list xmlns:android="http://schemas.android.com/apk/res/android">
    
    <item android:maxLevel="0" android:drawable="@drawable/home_arrows_right_4" />
    <item android:maxLevel="1" android:drawable="@drawable/home_arrows_right_3" />
    <item android:maxLevel="2" android:drawable="@drawable/home_arrows_right_2" />
    <item android:maxLevel="3" android:drawable="@drawable/home_arrows_right_1" />
    <item android:maxLevel="4" android:drawable="@android:color/transparent" />
   
</level-list>

大功告成 over

最后 说一个期间的一个知识
自定义控件的属性 declare-styleable

比如说 我们上面修改的 launcher:defaultScreen="2" 这个就是自定义的属性 因为这属性不是ViewGroup（workspace类是继承于ViewGroup）所定义的属性

1、在\res\values里面的attrs.xml里面定义

<resources>
<declare-styleable name="Workspace">
        <!-- The first screen the workspace should display. -->
        <attr name="defaultScreen" format="integer"  />
    </declare-styleable>

    <!-- CellLayout specific attributes. These attributes are used to customize
         a CellLayout view in XML files. -->
    <declare-styleable name="CellLayout">
        <!-- The width of a single cell -->
        <attr name="cellWidth" format="dimension"  />
        <!-- The height of a single cell -->
        <attr name="cellHeight" format="dimension"  />
        <!-- Padding to apply at the start of the long axis -->
        <attr name="longAxisStartPadding" format="dimension"  />
        <!-- Padding to apply at the end of the long axis -->
        <attr name="longAxisEndPadding" format="dimension"  />
        <!-- Padding to apply at the start of the short axis -->
        <attr name="shortAxisStartPadding" format="dimension"  />
        <!-- Padding to apply at the end of the short axis -->
        <attr name="shortAxisEndPadding" format="dimension"  />
        <!-- Number of cells on the short axis of the CellLayout -->
        <attr name="shortAxisCells" format="integer" />
        <!-- Number of cells on the long axis of the CellLayout -->
        <attr name="longAxisCells" format="integer" />
    </declare-styleable>
</resources>

<resources>
<declare-styleable name="Workspace">
        <!-- The first screen the workspace should display. -->
        <attr name="defaultScreen" format="integer"  />
    </declare-styleable>
    
    <!-- CellLayout specific attributes. These attributes are used to customize
         a CellLayout view in XML files. -->
    <declare-styleable name="CellLayout">
        <!-- The width of a single cell -->
        <attr name="cellWidth" format="dimension"  />
        <!-- The height of a single cell -->
        <attr name="cellHeight" format="dimension"  />
        <!-- Padding to apply at the start of the long axis -->
        <attr name="longAxisStartPadding" format="dimension"  />
        <!-- Padding to apply at the end of the long axis -->
        <attr name="longAxisEndPadding" format="dimension"  />
        <!-- Padding to apply at the start of the short axis -->
        <attr name="shortAxisStartPadding" format="dimension"  />
        <!-- Padding to apply at the end of the short axis -->
        <attr name="shortAxisEndPadding" format="dimension"  />
        <!-- Number of cells on the short axis of the CellLayout -->
        <attr name="shortAxisCells" format="integer" />
        <!-- Number of cells on the long axis of the CellLayout -->
        <attr name="longAxisCells" format="integer" />
    </declare-styleable>
</resources>

2、layout.xml引用

先申明xmlns:launcher="http://schemas.android.com/apk/res/com.lp.launcher"（R.java)，
这样就可以使用launcher:defaultScreen。

先申明xmlns:launcher="http://schemas.android.com/apk/res/com.lp.launcher"（R.java)，
这样就可以使用launcher:defaultScreen。

3、java文件取值

   public Workspace(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);

    TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.Workspace, defStyle, 0);
    mDefaultScreen = a.getInt(R.styleable.Workspace_defaultScreen, 2);
    a.recycle();

    initWorkspace();
}