package net.micode.notes.ui; import android.content.Context; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.PopupMenu; import android.widget.PopupMenu.OnMenuItemClickListener; import net.micode.notes.R; public class DropdownMenu { private Button mButton; private PopupMenu mPopupMenu; //声明一个下拉菜单 private Menu mMenu; public DropdownMenu(Context context, Button button, int menuId) { mButton = button; mButton.setBackgroundResource(R.drawable.dropdown_icon); //设置这个view的背景 mPopupMenu = new PopupMenu(context, mButton); mMenu = mPopupMenu.getMenu(); mPopupMenu.getMenuInflater().inflate(menuId, mMenu); //MenuInflater是用来实例化Menu目录下的Menu布局文件 //根据ID来确认menu的内容选项 mButton.setOnClickListener(new OnClickListener() { public void onClick(View v) { mPopupMenu.show(); } }); } public void setOnDropdownMenuItemClickListener(OnMenuItemClickListener listener) { if (mPopupMenu != null) { mPopupMenu.setOnMenuItemClickListener(listener); }//设置菜单的监听 } public MenuItem findItem(int id) { return mMenu.findItem(id); }//对于菜单选项的初始化,根据索引搜索菜单需要的选项 public void setTitle(CharSequence title) { mButton.setText(title); }//布局文件,设置标题 }