Android动画开发——Animation显示隐藏菜单效果

这里的菜单并不是按机器上的MENU出现在那种菜单，而是基于Android SDK提供的android.view.animation.TranslateAnimation（extends android.view.animation.Animation）类实例后附加到一个Layout上使之产生的有动画出现和隐藏效果的菜单。

Class TranslateAnimation的使用：Animation有两种定义方法，一种是用Java code，一种是用XML，这里只介绍用code来定义.

package com.cn.amenu;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.TranslateAnimation;
import android.widget.Button;
import android.widget.LinearLayout;

public class Amenu extends Activity {
private Animation mShowAction = null;
private Animation mHiddenAction = null;
private LinearLayout mMenu = null;
private Button mButton = null;
private boolean menuShowed;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

mMenu = (LinearLayout) this.findViewById(R.id.menu1);
mButton = (Button) this.findViewById(R.id.button01);
// 动画
mShowAction = new TranslateAnimation(Animation.RELATIVE_TO_SELF, 0.0f,
Animation.RELATIVE_TO_SELF, 0.0f, Animation.RELATIVE_TO_SELF,
-1.0f, Animation.RELATIVE_TO_SELF, 0.0f);
mShowAction.setDuration(500);
mHiddenAction = new TranslateAnimation(Animation.RELATIVE_TO_SELF,
0.0f, Animation.RELATIVE_TO_SELF, 0.0f,
Animation.RELATIVE_TO_SELF, 0.0f, Animation.RELATIVE_TO_SELF,
-1.0f);

mHiddenAction.setDuration(500);
menuShowed=false;
mMenu.setVisibility(View.GONE);
mButton.setOnClickListener(new btn_click());
}

class btn_click implements OnClickListener{

@Override
public void onClick(View arg0) {
if (menuShowed) {
menuShowed=false;
mMenu.startAnimation(mHiddenAction);
mMenu.setVisibility(View.GONE);
}else{
menuShowed=true;
mMenu.startAnimation(mShowAction);
mMenu.setVisibility(View.VISIBLE);
}
}
}
}

main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
<LinearLayout
android:id="@+id/menu1"
android:layout_width="fill_parent"
android:layout_height="50px"
android:layout_alignParentTop="true"
android:background="#ffffff">

<TextView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center"
android:text="i am a menu"
/>
<img src="http://dl.iteye.com/upload/attachment/498976/12e90b24-75e4-38bb-84ca-bfb6426c29ae.jpg" mce_src="http://dl.iteye.com/upload/attachment/498976/12e90b24-75e4-38bb-84ca-bfb6426c29ae.jpg" alt="">

</LinearLayout>
<Button
android:id="@+id/button01"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="click to show / hide menu"
/>
</RelativeLayout>

效果: