这一篇来使用逐帧动画和补间动画来实现一个小例子,首先我们来看看Android中的补间动画。
Android中使用Animation代表抽象的动画类,该类包括下面几个子类:
AlphaAnimation:透明改变动画。
ScaleAnimation:大小缩放动画。
TranslateAnimation:位移变化动画。
RotateAnimation:旋转动画。
我们下面使用位移动画和逐帧动画来实现这个小例子,先看看运行效果:
蝴蝶挥动翅膀的逐帧动画文件:
<?xml version="1.0" encoding="utf-8"?> <!-- 定义动画循环播放 --> <animation-list xmlns:android="http://schemas.android.com/apk/res/android" android:oneshot="false"> <item android:drawable="@drawable/butterfly_f01" android:duration="120" /> <item android:drawable="@drawable/butterfly_f02" android:duration="120" /> <item android:drawable="@drawable/butterfly_f03" android:duration="120" /> <item android:drawable="@drawable/butterfly_f04" android:duration="120" /> <item android:drawable="@drawable/butterfly_f05" android:duration="120" /> <item android:drawable="@drawable/butterfly_f06" android:duration="120" /> </animation-list>界面布局文件:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="@drawable/background" > <ImageView android:id="@+id/butterfly" android:layout_width="wrap_content" android:layout_height="wrap_content" android:background="@anim/butteryfly" /> </LinearLayout>具体逻辑及位移动画:
package com.example.butteryfly; import java.util.Timer; import java.util.TimerTask; import android.app.Activity; import android.graphics.drawable.AnimationDrawable; import android.os.Bundle; import android.os.Handler; import android.view.Display; import android.view.View; import android.view.View.OnClickListener; import android.view.animation.TranslateAnimation; import android.widget.ImageView; public class MainActivity extends Activity { private float curX = 0; private float curY = 30; private float nextX = 0; private float nextY = 0; private int windowW = 0; private int windowH = 0; private ImageView imageView; Handler handler = new Handler(){ public void handleMessage(android.os.Message msg) { if(msg.what == 0x123){ if(nextX > windowW || nextY > windowH){ curX = nextX = 0; }else{ nextX += 8; } nextY = curY + (float) (Math.random() * 20 - 10); TranslateAnimation anim = new TranslateAnimation(curX, nextX, curY, nextY); curX = nextX; curY = nextY; anim.setDuration(200); imageView.startAnimation(anim); } }; }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); imageView = (ImageView) findViewById(R.id.butterfly); Display display = getWindowManager().getDefaultDisplay(); windowW = display.getWidth(); windowH = display.getHeight(); final AnimationDrawable butterfly = (AnimationDrawable) imageView.getBackground(); imageView.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { butterfly.start(); new Timer().schedule(new TimerTask() { @Override public void run() { handler.sendEmptyMessage(0x123); } }, 0, 200); } }); } }