今天给大家介绍如何在Android下实现一个带动画效果的Tab Menu。Tab Menu的打开动画效果为自下而上的淡入推进效果，关闭效果为自上而下的淡出推出效果。
实现的效果图如下(没有找到合适的屏幕录像工具，只能截静态图)：
[图片] 程序运行效果
[代码] TabMenuActivity.java
package com.zhuozhuo;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.widget.TextView;
public class TabMenuActivity extends Activity {
/** Called when the activity is first created. */
TabView dockView;
TextView tv;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
tv = (TextView) findViewById(R.id.tv);
dockView = new DockView(this);
}
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_MENU) {//监听menu键
if(dockView.isOpen()) {
tv.setText("点击menu键打开dock");
dockView.closeDock();//关闭dock
}
else {
tv.setText("再次点击menu键或者back键关闭dock");
dockView.openDock();//打开dock
}
return true;
}
if (keyCode == KeyEvent.KEYCODE_BACK) {//监听back键
if(dockView.isOpen()) {//当dock打开时，按back键关闭dock
dockView.closeDock();
return true;
}
}
return super.onKeyDown(keyCode, event);
}
}
[代码] TabView.java
package com.zhuozhuo;
import android.app.Activity;
import android.content.Context;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.Animation.AnimationListener;
import android.view.animation.AnimationUtils;
import android.widget.Toast;
public class TabView {
private static final int INTERVAL_TIME = 50;// 每个tab之间的动画时间间隔ms
private View tab1;
private View tab2;
private View tab3;
private View tab4;
private Activity context;
private boolean isOpen;
public TabView(Activity context) {
this.context = context;
tab1 = context.findViewById(R.id.tab1);
tab2 = context.findViewById(R.id.tab2);
tab3 = context.findViewById(R.id.tab3);
tab4 = context.findViewById(R.id.tab4);
setOnClickListener(tab1, 1);
setOnClickListener(tab2, 2);
setOnClickListener(tab3, 3);
setOnClickListener(tab4, 4);
}
public void openDock() {//打开dock
tab(tab1, 0, true);
tab(tab2, INTERVAL_TIME * 1, true);
tab(tab3, INTERVAL_TIME * 2, true);
tab(tab4, INTERVAL_TIME * 3, true);
isOpen = true;
}
private void setOnClickListener(View view, final int pos) {
view.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(context, "view" + pos + " click!", Toast.LENGTH_SHORT).show();//点击tab时显示toast
closeDock();
}
});
}
private void tab(final View view,int delayTime,final boolean toOpen) {
view.postDelayed(new Runnable() {
@Override
public void run() {
Animation animation;
if(toOpen) {
view.setVisibility(View.VISIBLE);//动画开始前,设置view可见
animation = AnimationUtils.loadAnimation(context, R.anim.show_tab);
view.startAnimation(animation);
}
else {
animation = AnimationUtils.loadAnimation(context, R.anim.close_tab);
animation.setAnimationListener(new AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {
}
@Override
public void onAnimationRepeat(Animation animation) {
}
@Override
public void onAnimationEnd(Animation animation) {
view.setVisibility(View.INVISIBLE);//动画结束时,view不可见
}
});
view.startAnimation(animation);
}
}
}, delayTime);
}
public boolean isOpen() {
return isOpen;
}
public void closeDock() {//关闭dock
tab(tab1, 0, false);
tab(tab2, INTERVAL_TIME * 1, false);
tab(tab3, INTERVAL_TIME * 2, false);
tab(tab4, INTERVAL_TIME * 3, false);
isOpen = false;
}
}
