AnimatedPathView

介绍：

根据设置的path路径绘制图形的自定义view。结合属性动画就可以实现路径动画效果。AnimatedPathView的原理是用了DashPathEffect，DashPathEffect能将离散的点形成的路径模拟成连续的线条，这是一个非常有用的类。

运行效果：

使用说明：

关于path的使用请看这篇文章 Android画图之Path类的使用 

package com.mattkula.animatedpathview.sample;
import android.animation.ObjectAnimator;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewTreeObserver;
import android.view.animation.LinearInterpolator;
import com.mattkula.animatedpathview.library.AnimatedPathView;
public class MyActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        final AnimatedPathView view = (AnimatedPathView)findViewById(R.id.animated_path);
        ViewTreeObserver observer = view.getViewTreeObserver();
        if(observer != null){
            observer.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
                @Override
                public void onGlobalLayout() {
                    view.getViewTreeObserver().removeGlobalOnLayoutListener(this);
                    float\[\]\[\] points = new float\[\]\[\]{
                            {0, 0},
                            {view.getWidth(), 0},
                            {view.getWidth(), view.getHeight()},
                            {0, view.getHeight()},
                            {0, 0},
                            {view.getWidth(), view.getHeight()},
                            {view.getWidth(), 0},
                            {0, view.getHeight()}
                    };
                    view.setPath(points);
                }
            });
        }
        view.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                ObjectAnimator anim = ObjectAnimator.ofFloat(view, "percentage", 0.0f, 1.0f);
                anim.setDuration(2000);
                anim.setInterpolator(new LinearInterpolator());
                anim.start();
            }
        });
    }
}

xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              xmlns:app="http://schemas.android.com/apk/res/com.mattkula.animatedpathview.sample"
              android:orientation="vertical"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
        >
    <com.mattkula.animatedpathview.library.AnimatedPathView
            android:id="@+id/animated_path"
            android:layout_width="fill_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            app:strokeColor="@android:color/holo_red_light"
            app:strokeWidth="10"/>
    <TextView
            android:layout_width="fill_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:text="Press top half of screen"
            />
</LinearLayout>