【核心代碼】

package com.itheima.youkumenu85;

import com.itheima.youkumenu85.util.Util;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.RelativeLayout;

public class MainActivity extends Activity implements OnClickListener {

    private RelativeLayout rl_menu3;
private RelativeLayout rl_menu2;
private RelativeLayout rl_menu1;
private boolean menu3showing = true;
private boolean menu2showing = true;

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        rl_menu3 = (RelativeLayout) findViewById(R.id.rl_menu3);
        rl_menu2 = (RelativeLayout) findViewById(R.id.rl_menu2);
        rl_menu1 = (RelativeLayout) findViewById(R.id.rl_menu1);
        findViewById(R.id.btn_menu2).setOnClickListener(this);
        findViewById(R.id.btn_menu1).setOnClickListener(this);
    }

@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_menu2: // 鍗曞嚮浜嗚彍鍗?鎸夐挳
if (Util.hasAnimExecuting()) {
return;
}

if (menu3showing) {
// 闅愯棌鑿滃崟3
Util.hide(rl_menu3);
} else {
// 鏄劇ず鑿滃崟3
Util.show(rl_menu3);
}
menu3showing = !menu3showing;
break;
case R.id.btn_menu1: // 鍗曞嚮浜嗚彍鍗?鎸夐挳
if (Util.hasAnimExecuting()) {
return;
}

if (menu3showing) {
// 闅愯棌鑿滃崟3
Util.hide(rl_menu3);
menu3showing = false;

// 闅愯棌鑿滃崟2(寤惰繜)
Util.hide(rl_menu2, 300);
} else if (menu2showing) {
// 闅愯棌鑿滃崟2
Util.hide(rl_menu2);
} else {
// 鏄劇ず鑿滃崟2
Util.show(rl_menu2);
}
menu2showing = !menu2showing;
break;
}
}

}