本文实例讲述了Android编程实现QQ表情的发送和接收。分享给大家供大家参考，具体如下：

在自己做一个聊天应用练习的时候，需要用到表情，于是就想着模仿一下QQ表情，图片资源完全copy的QQ.apk，解压就可以得到，这里不细说。

下面将该应用中的表情模块功能抽离出来，以便自己以后复习回顾。。

先看一下效果图：

首先进入界面：（完全仿照QQ）

点击一下上面的表情图标：

选择一些表情，输入一些文字混合：

点击发送：

可以看到文字和表情图片都一起显示出来了。

下面列出一些关键代码：

表情工具类ExpressionUtil:

public class ExpressionUtil { /** * 对spanableString进行正则判断，如果符合要求，则以表情图片代替 * @param context * @param spannableString * @param patten * @param start * @throws SecurityException * @throws NoSuchFieldException * @throws NumberFormatException * @throws IllegalArgumentException * @throws IllegalAccessException */ public static void dealExpression(Context context,SpannableString spannableString, Pattern patten, int start) throws SecurityException, NoSuchFieldException, NumberFormatException, IllegalArgumentException, IllegalAccessException { Matcher matcher = patten.matcher(spannableString); while (matcher.find()) { String key = matcher.group(); if (matcher.start() < start) { continue; } Field field = R.drawable.class.getDeclaredField(key); int resId = Integer.parseInt(field.get(null).toString()); //通过上面匹配得到的字符串来生成图片资源id if (resId != 0) { Bitmap bitmap = BitmapFactory.decodeResource(context.getResources(), resId); ImageSpan imageSpan = new ImageSpan(bitmap); //通过图片资源id来得到bitmap，用一个ImageSpan来包装 int end = matcher.start() + key.length(); //计算该图片名字的长度，也就是要替换的字符串的长度 spannableString.setSpan(imageSpan, matcher.start(), end, Spannable.SPAN_INCLUSIVE_EXCLUSIVE); //将该图片替换字符串中规定的位置中 if (end < spannableString.length()) { //如果整个字符串还未验证完，则继续。。 dealExpression(context,spannableString, patten, end); } break; } } } /** * 得到一个SpanableString对象，通过传入的字符串,并进行正则判断 * @param context * @param str * @return */ public static SpannableString getExpressionString(Context context,String str,String zhengze){ SpannableString spannableString = new SpannableString(str); Pattern sinaPatten = Pattern.compile(zhengze, Pattern.CASE_INSENSITIVE); //通过传入的正则表达式来生成一个pattern try { dealExpression(context,spannableString, sinaPatten, 0); } catch (Exception e) { Log.e("dealExpression", e.getMessage()); } return spannableString; } }

在显示聊天页面的list的适配器中，我们需要做如下的显示，即调用上面工具类的方法：

SimpleChatAdapter中的内部类ViewHolder：

private class ViewHolder{ RelativeLayout chat_layout; ImageView image; TextView text; public ViewHolder(View convertView){ chat_layout=(RelativeLayout) convertView.findViewById(R.id.team_singlechat_id_listiteam); image=(ImageView) convertView.findViewById(R.id.team_singlechat_id_listiteam_headicon); text=(TextView) convertView.findViewById(R.id.team_singlechat_id_listiteam_message); } public void setData(MessageInfo msg){ RelativeLayout.LayoutParams rl_chat_left=((RelativeLayout.LayoutParams)chat_layout.getLayoutParams()); RelativeLayout.LayoutParams rl_tv_msg_left=((RelativeLayout.LayoutParams)text.getLayoutParams()); RelativeLayout.LayoutParams rl_iv_headicon_left=((RelativeLayout.LayoutParams)image.getLayoutParams()); if(!DicqConstant.DEFAULTMAC.equalsIgnoreCase(msg.getUsermac())){ //根据本地的mac地址来判断该条信息是属于本人所说还是对方所说 //如果是自己说的，则显示在右边；如果是对方所说，则显示在左边 rl_chat_left.addRule(RelativeLayout.ALIGN_PARENT_LEFT,-1); rl_chat_left.addRule(RelativeLayout.ALIGN_PARENT_RIGHT,0); rl_iv_headicon_left.addRule(RelativeLayout.ALIGN_PARENT_LEFT,-1); rl_iv_headicon_left.addRule(RelativeLayout.ALIGN_PARENT_RIGHT,0); rl_tv_msg_left.addRule(RelativeLayout.RIGHT_OF,R.id.team_singlechat_id_listiteam_headicon); rl_tv_msg_left.addRule(RelativeLayout.LEFT_OF,0); text.setBackgroundResource(R.drawable.balloon_l_selector); }else{ rl_chat_left.addRule(RelativeLayout.ALIGN_PARENT_LEFT,0); rl_chat_left.addRule(RelativeLayout.ALIGN_PARENT_RIGHT,-1); rl_iv_headicon_left.addRule(RelativeLayout.ALIGN_PARENT_LEFT,0); rl_iv_headicon_left.addRule(RelativeLayout.ALIGN_PARENT_RIGHT,-1); rl_tv_msg_left.addRule(RelativeLayout.RIGHT_OF,0); rl_tv_msg_left.addRule(RelativeLayout.LEFT_OF,R.id.team_singlechat_id_listiteam_headicon); text.setBackgroundResource(R.drawable.balloon_r_selector); } image.setImageResource(PrortaitUtils.conversionIdToRes(msg.getProtrait())); //设置头像 String str = msg.getMsg(); //消息具体内容 String zhengze = "f0[0-9]{2}|f10[0-7]"; //正则表达式，用来判断消息内是否有表情 try { SpannableString spannableString = ExpressionUtil.getExpressionString(context, str, zhengze); text.setText(spannableString); } catch (NumberFormatException e) { e.printStackTrace(); } catch (SecurityException e) { e.printStackTrace(); } catch (IllegalArgumentException e) { e.printStackTrace(); } } }

关于表情弹出框的实现如下：

MainActivity：

/** * 创建一个表情选择对话框 */ private void createExpressionDialog() { builder = new Dialog(MainActivity.this); GridView gridView = createGridView(); builder.setContentView(gridView); builder.setTitle("默认表情"); builder.show(); gridView.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView arg0, View arg1, int arg2, long arg3) { Bitmap bitmap = null; bitmap = BitmapFactory.decodeResource(getResources(), imageIds[arg2 % imageIds.length]); ImageSpan imageSpan = new ImageSpan(MainActivity.this, bitmap); String str = null; if(arg2