900字范文 > 自定义viewgroup实现ArcMenu

自定义viewgroup实现ArcMenu

时间：2019-05-06 23:19:51

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(PLEX_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(PLEX_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

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;@Overrideprotected 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MenuItemImageView people = new ImageView(this);people.setImageResource(poser_with);people.setTag("People");mArcMenuLeftTop.addView(people);mArcMenuLeftTop.setOnMenuItemClickListener(new OnMenuItemClickListener(){@Overridepublic void onClick(View view, int pos){Toast.makeText(MainActivity.this,pos + ":" + view.getTag(), Toast.LENGTH_SHORT).show();}});}}