Android编写简单的聊天室应用
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2024-03-01 23:09:04
最近写了一个简单的聊天室应用,可以发送表情,更改头像这些功能。主要技术点就是怎样把表情图片放到textview等ui控件中展示。这里废话不多说,下面是效果图:
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最近写了一个简单的聊天室应用,可以发送表情,更改头像这些功能。主要技术点就是怎样把表情图片放到textview等ui控件中展示。这里废话不多说,下面是效果图:
这里主要讲下怎样把文本替换到表情,先说下思路,首先我们的图片是保存在本地资源目录drawable中而所有的资源文件都是r这个类来管理,所以我们可以利用正则表达式找出图片id包装成imagespan然后把imagespan放到spannablestring中,最后把spannablestring放入edittext中,下面是源码:
package com.coreandroid.util; import java.lang.reflect.field; import java.util.regex.matcher; import java.util.regex.pattern; import android.content.context; import android.text.spannable; import android.text.spannablestring; import android.text.style.imagespan; import android.util.log; import com.coreandroid.chart.r; 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 */ public static void matchexpression(context context, spannablestring spannablestring, pattern patten, int start) throws exception { 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 = field.getint(null); // 通过上面匹配得到的字符串来生成图片资源id if (resid != 0) { imagespan imagespan = new imagespan(context, resid); // 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_exclusive_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。。 matchexpression(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 spannablestring */ public static spannablestring getexpressionstring(context context, string str, string zhengze) { spannablestring spannablestring = new spannablestring(str); pattern sinapatten = pattern.compile(zhengze); // 通过传入的正则表达式来生成一个pattern try { matchexpression(context, spannablestring, sinapatten, 0); } catch (exception e) { log.e("dealexpression", e.getmessage()); } return spannablestring; } }
下面是聊天记录列表的adapter,这里主要是动态的改变每个item的布局来区分是自己还是他人的发言,具体源码如下:
package com.coreandroid.adapter; import java.text.dateformat; import java.text.simpledateformat; import java.util.date; import java.util.list; import android.content.context; import android.text.spannablestring; import android.text.textutils; import android.view.layoutinflater; import android.view.view; import android.view.viewgroup; import android.widget.baseadapter; import android.widget.imageview; import android.widget.relativelayout; import android.widget.textview; import com.coreandroid.chart.r; import com.coreandroid.entity.messageinfo; import com.coreandroid.util.commonutils; import com.coreandroid.util.expressionutil; public class chartlistadapter extends baseadapter { private context context; private layoutinflater inflater; private list<messageinfo> data; private dateformat df; public chartlistadapter(context context, list<messageinfo> data) { super(); this.context = context; inflater = layoutinflater.from(context); this.data = data; df = new simpledateformat("yyyy-mm-dd hh:mm:ss"); } @override public int getcount() { return data.size(); } @override public object getitem(int position) { return data.get(position); } @override public long getitemid(int position) { return position; } @override public view getview(int position, view convertview, viewgroup parent) { viewholder holder = null; if (convertview == null) { convertview = inflater.inflate(r.layout.chart_list_item, null); holder = new viewholder(convertview); convertview.settag(holder); } else { holder = (viewholder) convertview.gettag(); } holder.setdata((messageinfo) getitem(position)); return convertview; } private class viewholder { private imageview image; private textview text; private textview title; private relativelayout rl; public viewholder(view convertview) { image = (imageview) convertview .findviewbyid(r.id.chart_list_item_headicon); text = (textview) convertview .findviewbyid(r.id.chart_list_item_message); title = (textview) convertview .findviewbyid(r.id.chart_list_item_title); rl = (relativelayout) convertview .findviewbyid(r.id.rl_chart_list_bottom); } public void setdata(messageinfo msg) { relativelayout.layoutparams rl_tv_msg_left = (relativelayout.layoutparams) text .getlayoutparams(); relativelayout.layoutparams rl_iv_headicon_left = (relativelayout.layoutparams) image .getlayoutparams(); relativelayout.layoutparams rl_tv_title = (relativelayout.layoutparams) title .getlayoutparams(); relativelayout.layoutparams rl_buttom = (relativelayout.layoutparams) rl .getlayoutparams(); if (!commonutils.getdeviceid().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_buttom.addrule(relativelayout.align_parent_top); rl_tv_title.addrule(relativelayout.align_parent_bottom); rl_tv_title.addrule(relativelayout.align_parent_left); rl_tv_title.addrule(relativelayout.below, r.id.rl_chart_list_bottom); rl_iv_headicon_left.addrule(relativelayout.align_parent_left); rl_iv_headicon_left.addrule(relativelayout.align_parent_bottom); rl_tv_msg_left.addrule(relativelayout.right_of, r.id.chart_list_item_headicon); text.setbackgroundresource(r.drawable.incoming); string titlestr = msg.getusermac() + "-" + df.format(new date()); title.settext(titlestr); } else { rl_buttom.addrule(relativelayout.align_parent_top); rl_tv_title.addrule(relativelayout.align_parent_bottom); rl_tv_title.addrule(relativelayout.align_parent_right); rl_tv_title.addrule(relativelayout.below, r.id.rl_chart_list_bottom); rl_iv_headicon_left.addrule(relativelayout.align_parent_right); rl_iv_headicon_left.addrule(relativelayout.align_parent_bottom); rl_tv_msg_left.addrule(relativelayout.left_of, r.id.chart_list_item_headicon); text.setbackgroundresource(r.drawable.outgoing); string titlestr = df.format(new date()) + "-" + msg.getusermac(); title.settext(titlestr); } if (!textutils.isempty(msg.getheadimage())) { image.setimagebitmap(commonutils.strconvertbitmap(msg .getheadimage())); // 设置头像 } else { image.setimageresource(r.drawable.im); } string str = msg.getmessage(); // 消息具体内容 try { spannablestring spannablestring = expressionutil .getexpressionstring(context, str, commonutils.pattern); text.settext(spannablestring); } catch (exception e) { e.printstacktrace(); } } } }
源码下载:android聊天室应用
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