EChat(简易聊天项目)五、存储聊天记录中的图片

本文链接：https://blog.youkuaiyun.com/niding6282/article/details/79365700

本文详细介绍了EChat聊天项目中如何实现存储聊天记录中的图片功能。通过更新Msg类添加图片路径字段，修改MsgAdapter以处理图片存储及消息类型判断，更新MessageActivity以支持相册选择图片，以及调整布局文件来展示图片消息。最终，实现了用户可以从相册选择图片并成功发送，同时图片被正确存储到本地。

利用文件存储实现存储聊天记录中的图片

首先先需要使聊天界面可以发送图片，然后再对其进行存储操作

①修改Msg类，增加了imgpath,即图片路径

public class Msg {
    public static final int TYPE_RECEIVED = 0;
    public static final int TYPE_SENT = 1;
    public static final int TYPE_RECEIVED_IMG = 2;
    public static final int TYPE_SENT_IMG = 3;
    private String content;
    private String imgpath;
    private int type;

    public Msg(String content,String imgpath, int type){
        this.content = content;
        this.imgpath = imgpath;
        this.type = type;
    }
    public String getContent(){
        return content;
    }
    public int getType(){
        return type;
    }

    public String getImgpath() {
        return imgpath;
    }
}

②对MsgAdapter进行了大部分修改，添加了图片有关部分，以及图片的存储到本地，以及将消息的各部分分开处理，原先只有收发两类，现修改成了switch语句判断，有文字消息的收发和图片消息的收发，同时也更加便于之后的拓展

public class MsgAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{
    private List<Msg> mMsgList;

    static class R_MsgViewHolder extends RecyclerView.ViewHolder{
        LinearLayout rightLayout;
        TextView rightMsg;

        public R_MsgViewHolder(View view){
            super(view);
            rightLayout = (LinearLayout)view.findViewById(R.id.right_layout);
            rightMsg = (TextView)view.findViewById(R.id.right_msg);
        }
    }

    static class L_MsgViewHolder extends RecyclerView.ViewHolder{
        LinearLayout leftLayout;
        TextView leftMsg;

        public L_MsgViewHolder(View view){
            super(view);
            leftLayout = (LinearLayout)view.findViewById(R.id.left_layout);
            leftMsg = (TextView)view.findViewById(R.id.left_msg);
        }
    }

    static class R_ImgViewHolder extends RecyclerView.ViewHolder{
        LinearLayout rightlayout_img;
        ImageView rightImage;

        public R_ImgViewHolder(View view){
            super(view);
            rightlayout_img = (LinearLayout)view.findViewById(R.id.right_layout_img);
            rightImage = (ImageView)view.findViewById(R.id.right_image);
        }
    }

    static class L_ImgViewHolder extends RecyclerView.ViewHolder{
        LinearLayout leftlayout_img;
        ImageView leftImage;

        public L_ImgViewHolder(View view){
            super(view);
            leftlayout_img = (LinearLayout)view.findViewById(R.id.left_layout_img);
            leftImage = (ImageView)view.findViewById(R.id.left_image);
        }
    }

    public MsgAdapter(List<Msg> msgList){
        mMsgList = msgList;
    }
    @Override
    public RecyclerView.ViewHolder onC