接上文
上一篇文章中主要讲了GridView的简单应用，以网格的形式展示了一些图片，对于图片也有点击
监听操作。但是，如果我们在浏览图片的时候需要一些选中操作、甚至是多选操作的时候。这样的
功能我们又该如何实现呢？
可以使用ActionBar +GridView的形式实现！在谈及具体实现之前，首先我们先了解一下什么是
ActionBar：
Action Bar是活动中的一种控件，用以代替传统的品目顶端的标题栏，它提供了多便利性。有关
其详细内容会在以后研究，现在主要考虑上述需求的实现。
先上效果图
首先是关于ActionBar的布局文件：主要是用于实现全选与全不选的功能的。
GridView 选中%s个 全选 全不选 package com.kiritor; /** * @author Kiritor * 实现自己的View继承Checable接口*/ import android.content.Context; import android.util.AttributeSet; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.widget.Checkable; import android.widget.ImageView; import android.widget.RelativeLayout; public class GridItem extends RelativeLayout implements Checkable { private Context mContext; private boolean mChecked;//判断该选项是否被选上的标志量 private ImageView mImgView = null; private ImageView mSecletView = null; public GridItem(Context context) { this(context, null, 0); } public GridItem(Context context, AttributeSet attrs) { this(context, attrs, 0); } public GridItem(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); // TODO Auto-generated constructor stub mContext = context; LayoutInflater.from(mContext).inflate(R.layout.grid_item, this); mImgView = (ImageView) findViewById(R.id.img_view); mSecletView = (ImageView) findViewById(R.id.select); } @Override public void setChecked(boolean checked) { // TODO Auto-generated method stub mChecked = checked; setBackgroundDrawable(checked ? getResources().getDrawable( R.drawable.background) : null); mSecletView.setVisibility(checked ? View.VISIBLE : View.GONE);//选上了则显示小勾图片 } @Override public boolean isChecked() { // TODO Auto-generated method stub return mChecked; } @Override public void toggle() { setChecked(!mChecked); } public void setImgResId(int resId) { if (mImgView != null) { mImgView.setBackgroundResource(resId);//设置背景 } } } package com.kiritor; import java.util.HashMap; import java.util.Map; import java.util.Set; import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.view.ActionMode; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.widget.AbsListView.LayoutParams; import android.widget.AbsListView.MultiChoiceModeListener; import android.widget.BaseAdapter; import android.widget.Checkable; import android.widget.FrameLayout; import android.widget.GridView; import android.widget.ImageView; import android.widget.ListAdapter; import android.widget.TextView; public class HomeActivity extends Activity implements MultiChoiceModeListener { private GridView mGridView; private GridAdapter mGridAdapter; private TextView mActionText; private static final int MENU_SELECT_ALL = 0; private static final int MENU_UNSELECT_ALL = MENU_SELECT_ALL + 1; private Map mSelectMap = new HashMap(); private int[] mImgIds = new int[] { R.drawable.img_1, R.drawable.img_2, R.drawable.img_3, R.drawable.img_4, R.drawable.img_5, R.drawable.img_6, R.drawable.img_7, R.drawable.img_8, R.drawable.img_9, R.drawable.img_1, R.drawable.img_2, R.drawable.img_3, R.drawable.img_4, R.drawable.img_5, R.drawable.img_6, R.drawable.img_7, R.drawable.img_3, R.drawable.img_4, R.drawable.img_5, R.drawable.img_5 }; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mGridView = (GridView) findViewById(R.id.gridview); mGridView.setChoiceMode(GridView.CHOICE_MODE_MULTIPLE_MODAL);// 设置为多选模式 mGridAdapter = new GridAdapter(this); mGridView.setAdapter(mGridAdapter);// 数据适配 mGridView.setMultiChoiceModeListener(this);// 设置多选模式监听器 } /** Override MultiChoiceModeListener start **/ @Override public boolean onCreateActionMode(ActionMode mode, Menu menu) { // TODO Auto-generated method stub // 得到布局文件的View View v = LayoutInflater.from(this).inflate(R.layout.actionbar_layout, null); mActionText = (TextView) v.findViewById(R.id.action_text); // 设置显示内容为GridView选中的项目个数 mActionText.setText(formatString(mGridView.getCheckedItemCount())); // 设置动作条的视图 mode.setCustomView(v); // 得到菜单 getMenuInflater().inflate(R.menu.action_menu, menu); return true; } @Override public boolean onPrepareActionMode(ActionMode mode, Menu menu) { // TODO Auto-generated method stub /* 初始状态下,如果选中的项数不等于总共的项数,设置"全选"的状态为True */ menu.getItem(MENU_SELECT_ALL).setEnabled( mGridView.getCheckedItemCount() != mGridView.getCount()); return true; } @Override public boolean onActionItemClicked(ActionMode mode, MenuItem item) { // TODO Auto-generated method stub /* * 当点击全选的时候,全选 点击全不选的时候全不选 */ switch (item.getItemId()) { case R.id.menu_select: for (int i = 0; i < mGridView.getCount(); i++) { mGridView.setItemChecked(i, true); mSelectMap.put(i, true); } break; case R.id.menu_unselect: for (int i = 0; i < mGridView.getCount(); i++) { mGridView.setItemChecked(i, false); mSelectMap.clear(); } break; } return true; } @Override public void onDestroyActionMode(ActionMode mode) { // TODO Auto-generated method stub mGridAdapter.notifyDataSetChanged(); } @Override public void onItemCheckedStateChanged(ActionMode mode, int position, long id, boolean checked) { // TODO Auto-generated method stub // 当每个项状态改变的时候的操作 mActionText.setText(formatString(mGridView.getCheckedItemCount())); mSelectMap.put(position, checked);/* 放入选中的集合中 */ mode.invalidate(); } /** Override MultiChoiceModeListener end **/ private String formatString(int count) { return String.format(getString(R.string.selection), count); } private class GridAdapter extends BaseAdapter { private Context mContext; public GridAdapter(Context ctx) { mContext = ctx; } @Override public int getCount() { // TODO Auto-generated method stub return mImgIds.length; } @Override public Integer getItem(int position) { // TODO Auto-generated method stub return Integer.valueOf(mImgIds[position]); } @Override public long getItemId(int position) { // TODO Auto-generated method stub return position; } @SuppressWarnings("deprecation") @Override /* 得到View */ public View getView(int position, View convertView, ViewGroup parent) { GridItem item; if (convertView == null) { item = new GridItem(mContext); item.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT)); } else { item = (GridItem) convertView; } item.setImgResId(getItem(position)); item.setChecked(mSelectMap.get(position) == null ? false : mSelectMap.get(position)); return item; } } } 完整源码:
http://download.csdn.net/detail/kiritor/5144666