最终效果如下
实现思路
通过效果图，会有几个问题：
a、动画效果如何实现
可以看出动画是从顶点外外发射的，可能有人说，那还不简单，默认元素都在定点位置，然后TraslateAnimation就好了；这样忽略了一点，就是TraslateAnimation虽然有动画效果，但是本质是不会改变按钮的位置，我们的按钮动画结束是要点击的；有人可能会说那使用属性动画，或者改变leftMagin,rightMagin；这样可能比较麻烦，其实我们可以默认让子菜单就已经在目标位置，然后GONE，当点击时还是用TraslateAnimation，把起始位置设为定点，终点位置就是我们隐藏的区域，动画结束VISIBLE.
b、如何确定位置呢？
每次会根据子菜单数量，算出a这个角度，然后通过sin , cos 分别算出每个子菜单的left , top ;
当然这是在左上的情况，如果在右上，则top还是和左上一致的，left则为 (屏幕宽度-左上算出的left) ;其他两个方位同理~
整体我通过自定义一个ViewGroup，这个ViewGroup中第一个子元素为点击的按钮（你可以随便布局，随便用什么控件），接下来的子元素我认为是菜单项。根据效果图，决定展开半径和显示的位置，让用户自己去定制。下面看具体实现：
自定义View的属性
<?xml version="1.0" encoding="utf-8"?>
<resources>
<attr name="position">
<enum name="left_top" value="0" />
<enum name="right_top" value="1" />
<enum name="right_bottom" value="2" />
<enum name="left_bottom" value="3" />
</attr>
<attr name="radius" format="dimension"></attr>
<declare-styleable name="ArcMenu">
<attr name="position" />
<attr name="radius"/>
</declare-styleable>
</resources>在自定义的ViewGroup中获取这些属性
/**
* @author zhy
*/
public class ArcMenu extends ViewGroup implements OnClickListener
{
private static final String TAG = "ArcMenu";
/**
* 菜单的显示位置
*/
private Position mPosition = Position.LEFT_TOP;
/**
* 菜单显示的半径，默认100dp
*/
private int mRadius = 100;
/**
* 用户点击的按钮
*/
private View mButton;
/**
* 当前ArcMenu的状态
*/
private Status mCurrentStatus = Status.CLOSE;
/**
* 回调接口
*/
private OnMenuItemClickListener onMenuItemClickListener;
/**
* 状态的枚举类
*
* @author zhy
*
*/
public enum Status
{
OPEN, CLOSE
}
/**
* 设置菜单现实的位置，四选1，默认右下
*
* @author zhy
*/
public enum Position
{
LEFT_TOP, RIGHT_TOP, RIGHT_BOTTOM, LEFT_BOTTOM;
}
public interface OnMenuItemClickListener
{
void onClick(View view, int pos);
}
public ArcMenu(Context context)
{
this(context, null);
}
public ArcMenu(Context context, AttributeSet attrs)
{
this(context, attrs, 0);
}
/**
* 初始化属性
*
* @param context
* @param attrs
* @param defStyle
*/
public ArcMenu(Context context, AttributeSet attrs, int defStyle)
{
super(context, attrs, defStyle);
// dp convert to px
mRadius = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
mRadius, getResources().getDisplayMetrics());
TypedArray a = context.getTheme().obtainStyledAttributes(attrs,
R.styleable.ArcMenu, defStyle, 0);
int n = a.getIndexCount();
for (int i = 0; i < n; i++)
{
int attr = a.getIndex(i);
switch (attr)
{
case R.styleable.ArcMenu_position:
int val = a.getInt(attr, 0);
switch (val)
{
case 0:
mPosition = Position.LEFT_TOP;
break;
case 1:
mPosition = Position.RIGHT_TOP;
break;
case 2:
mPosition = Position.RIGHT_BOTTOM;
break;
case 3:
mPosition = Position.LEFT_BOTTOM;
break;
}
break;
case R.styleable.ArcMenu_radius:
// dp convert to px
mRadius = a.getDimensionPixelSize(attr, (int) TypedValue
.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 100f,
getResources().getDisplayMetrics()));
break;
}
}
a.recycle();
}计算子元素的大小
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
int count = getChildCount();
for (int i = 0; i < count; i++)
{
// mesure child
getChildAt(i).measure(MeasureSpec.UNSPECIFIED,
MeasureSpec.UNSPECIFIED);
}
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
} 确定子元素的位置
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b)
{
if (changed)
{
layoutButton();
int count = getChildCount();
/**
* 设置所有孩子的位置 例如(第一个为按钮)： 左上时，从左到右 ] 第2个：mRadius(sin0 , cos0)
* 第3个：mRadius(sina ,cosa) 注：[a = Math.PI / 2 * (cCount - 1)]
* 第4个：mRadius(sin2a ,cos2a) 第5个：mRadius(sin3a , cos3a) ...
*/
for (int i = 0; i < count - 1; i++)
{
View child = getChildAt(i + 1);
child.setVisibility(View.GONE);
int cl = (int) (mRadius * Math.sin(Math.PI / 2 / (count - 2)
* i));
int ct = (int) (mRadius * Math.cos(Math.PI / 2 / (count - 2)
* i));
// childview width
int cWidth = child.getMeasuredWidth();
// childview height
int cHeight = child.getMeasuredHeight();
// 右上，右下
if (mPosition == Position.LEFT_BOTTOM
|| mPosition == Position.RIGHT_BOTTOM)
{
ct = getMeasuredHeight() - cHeight - ct;
}
// 右上，右下
if (mPosition == Position.RIGHT_TOP
|| mPosition == Position.RIGHT_BOTTOM)
{
cl = getMeasuredWidth() - cWidth - cl;
}
Log.e(TAG, cl + " , " + ct);
child.layout(cl, ct, cl + cWidth, ct + cHeight);
}
}
} 首先在layoutButton中对按钮位置就行设置，以及初始化点击事件；然后从第二个子元素开始为菜单项，分别设置其位置，计算的原理就是上面我画的草图，可以再去仔细看看，动手在纸上画一画
/**
* 第一个子元素为按钮，为按钮布局且初始化点击事件
*/
private void layoutButton()
{
View cButton = getChildAt(0);
cButton.setOnClickListener(this);
int l = 0;
int t = 0;
int width = cButton.getMeasuredWidth();
int height = cButton.getMeasuredHeight();
switch (mPosition)
{
case LEFT_TOP:
l = 0;
t = 0;
break;
case LEFT_BOTTOM:
l = 0;
t = getMeasuredHeight() - height;
break;
case RIGHT_TOP:
l = getMeasuredWidth() - width;
t = 0;
break;
case RIGHT_BOTTOM:
l = getMeasuredWidth() - width;
t = getMeasuredHeight() - height;
break;
}
Log.e(TAG, l + " , " + t + " , " + (l + width) + " , " + (t + height));
cButton.layout(l, t, l + width, t + height);
} 这是定位Button的代码，此时的代码已经实现了定位，如果你把onLayout中childView.setVisibility(VISIBLE)。ArcMenu的整个控件的样子已经实现了，接下来就是点击事件，已经效果动画的实现了。
设置按钮点击事件
/**
* 为按钮添加点击事件
*/
@Override
public void onClick(View v)
{
mButton = findViewById(R.id.id_button);
if (mButton == null)
{
mButton = getChildAt(0);
}
rotateView(mButton, 0f, 270f, 300);
toggleMenu(300);
} /**
* 按钮的旋转动画
*
* @param view
* @param fromDegrees
* @param toDegrees
* @param durationMillis
*/
public static void rotateView(View view, float fromDegrees,
float toDegrees, int durationMillis)
{
RotateAnimation rotate = new RotateAnimation(fromDegrees, toDegrees,
Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
0.5f);
rotate.setDuration(durationMillis);
rotate.setFillAfter(true);
view.startAnimation(rotate);
}
public void toggleMenu(int durationMillis)
{
int count = getChildCount();
for (int i = 0; i < count - 1; i++)
{
final View childView = getChildAt(i + 1);
childView.setVisibility(View.VISIBLE);
int xflag = 1;
int yflag = 1;
if (mPosition == Position.LEFT_TOP
|| mPosition == Position.LEFT_BOTTOM)
xflag = -1;
if (mPosition == Position.LEFT_TOP
|| mPosition == Position.RIGHT_TOP)
yflag = -1;
// child left
int cl = (int) (mRadius * Math.sin(Math.PI / 2 / (count - 2) * i));
// child top
int ct = (int) (mRadius * Math.cos(Math.PI / 2 / (count - 2) * i));
AnimationSet animset = new AnimationSet(true);
Animation animation = null;
if (mCurrentStatus == Status.CLOSE)
{// to open
animset.setInterpolator(new OvershootInterpolator(2F));
animation = new TranslateAnimation(xflag * cl, 0, yflag * ct, 0);
childView.setClickable(true);
childView.setFocusable(true);
} else
{// to close
animation = new TranslateAnimation(0f, xflag * cl, 0f, yflag
* ct);
childView.setClickable(false);
childView.setFocusable(false);
}
animation.setAnimationListener(new AnimationListener()
{
public void onAnimationStart(Animation animation)
{
}
public void onAnimationRepeat(Animation animation)
{
}
public void onAnimationEnd(Animation animation)
{
if (mCurrentStatus == Status.CLOSE)
childView.setVisibility(View.GONE);
}
});
animation.setFillAfter(true);
animation.setDuration(durationMillis);
// 为动画设置一个开始延迟时间，纯属好看，可以不设
animation.setStartOffset((i * 100) / (count - 1));
RotateAnimation rotate = new RotateAnimation(0, 720,
Animation.RELATIVE_TO_SELF, 0.5f,
Animation.RELATIVE_TO_SELF, 0.5f);
rotate.setDuration(durationMillis);
rotate.setFillAfter(true);
animset.addAnimation(rotate);
animset.addAnimation(animation);
childView.startAnimation(animset);
final int index = i + 1;
childView.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
if (onMenuItemClickListener != null)
onMenuItemClickListener.onClick(childView, index - 1);
menuItemAnin(index - 1);
changeStatus();
}
});
}
changeStatus();
Log.e(TAG, mCurrentStatus.name() +"");
} 点击时，触发TanslateAnimation动画，从定点向外扩展，也给点击按钮添加了一个旋转动画，每个子菜单项同样添加了旋转动画，且如果用户设置回调，调用回调接口；设置子菜单的点击事件。整体就是点击然后动画效果~~
设置子菜单的点击事件
/**
* 开始菜单动画，点击的MenuItem放大消失，其他的缩小消失
* @param item
*/
private void menuItemAnin(int item)
{
for (int i = 0; i < getChildCount() - 1; i++)
{
View childView = getChildAt(i + 1);
if (i == item)
{
childView.startAnimation(scaleBigAnim(300));
} else
{
childView.startAnimation(scaleSmallAnim(300));
}
childView.setClickable(false);
childView.setFocusable(false);
}
}
/**
* 缩小消失
* @param durationMillis
* @return
*/
private Animation scaleSmallAnim(int durationMillis)
{
Animation anim = new ScaleAnimation(1.0f, 0f, 1.0f, 0f,
Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
0.5f);
anim.setDuration(durationMillis);
anim.setFillAfter(true);
return anim;
}
/**
* 放大，透明度降低
* @param durationMillis
* @return
*/
private Animation scaleBigAnim(int durationMillis)
{
AnimationSet animationset = new AnimationSet(true);
Animation anim = new ScaleAnimation(1.0f, 4.0f, 1.0f, 4.0f,
Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
0.5f);
Animation alphaAnimation = new AlphaAnimation(1, 0);
animationset.addAnimation(anim);
animationset.addAnimation(alphaAnimation);
animationset.setDuration(durationMillis);
animationset.setFillAfter(true);
return animationset;
} 点击的菜单项变大且慢慢透明消失，未点击的菜单项缩小消失~有兴趣的可以改成自己喜欢的动画~
注：动画效果很多借鉴了eoe上那位仁兄的代码，这类动画也比较简单，就不多说了~
好了，剩下就是些getter，setter了~
布局文件
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:zhy="http://schemas.android.com/apk/res/com.example.zhy_arcmenu"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<com.example.zhy_arcmenu.ArcMenu
android:id="@+id/id_arcmenu1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
zhy:position="left_top"
zhy:radius="130dp" >
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/composer_button" >
<ImageView
android:id="@+id/id_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_icn_plus" />
</RelativeLayout>
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_camera"
android:tag="Camera" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_sun"
android:tag="Sun" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_place"
android:tag="Place" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_sleep"
android:tag="Sleep" />
</com.example.zhy_arcmenu.ArcMenu>
<com.example.zhy_arcmenu.ArcMenu
android:layout_width="fill_parent"
android:layout_height="fill_parent"
zhy:position="right_bottom"
zhy:radius="130dp" >
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/composer_button" >
<ImageView
android:id="@+id/id_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_icn_plus" />
</RelativeLayout>
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_camera"
android:tag="Camera" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_sun"
android:tag="Sun" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_place"
android:tag="Place" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_sleep"
android:tag="Sleep" />
</com.example.zhy_arcmenu.ArcMenu>
<com.example.zhy_arcmenu.ArcMenu
android:layout_width="fill_parent"
android:layout_height="fill_parent"
zhy:position="left_bottom"
zhy:radius="130dp" >
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/composer_button" >
<ImageView
android:id="@+id/id_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_icn_plus" />
</RelativeLayout>
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_sun"
android:tag="Sun" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_place"
android:tag="Place" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_sleep"
android:tag="Sleep" />
</com.example.zhy_arcmenu.ArcMenu>
<com.example.zhy_arcmenu.ArcMenu
android:layout_width="fill_parent"
android:layout_height="fill_parent"
zhy:position="right_top"
zhy:radius="130dp" >
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/composer_button" >
<ImageView
android:id="@+id/id_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_icn_plus" />
</RelativeLayout>
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_camera"
android:tag="Camera" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_sun"
android:tag="Sun" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_place"
android:tag="Place" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="@drawable/composer_sleep"
android:tag="Sleep" />
</com.example.zhy_arcmenu.ArcMenu>
</RelativeLayout>MainActivity
package com.example.zhy_arcmenu;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.widget.ImageView;
import android.widget.Toast;
import com.example.zhy_arcmenu.ArcMenu.OnMenuItemClickListener;
public class MainActivity extends Activity
{
private ArcMenu mArcMenuLeftTop;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mArcMenuLeftTop = (ArcMenu) findViewById(R.id.id_arcmenu1);
//动态添加一个MenuItem
ImageView people = new ImageView(this);
people.setImageResource(R.drawable.composer_with);
people.setTag("People");
mArcMenuLeftTop.addView(people);
mArcMenuLeftTop
.setOnMenuItemClickListener(new OnMenuItemClickListener()
{
@Override
public void onClick(View view, int pos)
{
Toast.makeText(MainActivity.this,
pos + ":" + view.getTag(), Toast.LENGTH_SHORT)
.show();
}
});
}
}注意
本文中用到了android TypedValue.applyDimension，这个方法是转变为标准尺寸的一个函数
参考链接
android TypedValue.applyDimension()的作用 - BuleRiver的专栏 - 博客频道 - CSDN.NET
Animation.setFillAfter and Animation.setFillBefore的作用
动画终止时停留在最后一帧~不然会回到没有执行之前的状态
参考链接
Animation.setFillAfter and Animation.setFillBefore的作用 - PuerTea - 博客园
关于animation的详细介绍
详情参见
【TweenedAnimation】四种动画效果参数详解(自测所得) - 邪天殇 - 博客园
Animation & Property Animation 使用 - Ajian_studio - 博客频道 - CSDN.NET
本文主要参考
Android 自定义ViewGroup手把手教你实现ArcMenu - Hongyang - 博客频道 - CSDN.NET