Android animation detail series [2] -- flying butterfly

This article uses frame-by-frame animation and complementary animation to implement a small example. First, let's take a look at the complementary animation in Android.

In Android, Animation is used to represent an abstract Animation class. This class includes the following sub-classes:

AlphaAnimation: transparent animation change.

ScaleAnimation: resize animation.

TranslateAnimation: displacement change animation.

RotateAnimation: rotation animation.

Let's use the displacement animation and frame-by-frame animation to implement this small example. Let's first look at the running effect:

Frame-by-frame animation file for butterfly wings:

<? Xml version = "1.0" encoding = "UTF-8"?> <! -- Define the animation Loop play --> <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" type = "codeph" text = "/codeph"/> <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>

Interface layout file:

<?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"><ImageViewandroid:id="@+id/butterfly"android:layout_width="wrap_content" android:layout_height="wrap_content" android:background="@anim/butteryfly"/></LinearLayout>

Specific logic and displacement Animation:

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);}};};@Overrideprotected 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() {@Overridepublic void onClick(View arg0) {butterfly.start();new Timer().schedule(new TimerTask() {@Overridepublic void run() {handler.sendEmptyMessage(0x123);}}, 0, 200);}});}}