Android实现风蓝记事本（3）：记事本启动类实现

Dear 丶 2022-05-24 04:13 256阅读 0赞

打开记事本就能看到之前记录的信息：

package com.example.notes;
    
    import java.util.ArrayList;
    import java.util.HashMap;
    import java.util.List;
    import java.util.Map;
    
    import android.app.Activity;
    import android.app.Dialog;
    import android.content.DialogInterface;
    import android.content.DialogInterface.OnKeyListener;
    import android.content.SharedPreferences.Editor;
    import android.content.Context;
    import android.content.Intent;
    import android.content.SharedPreferences;
    import android.database.Cursor;
    import android.os.Bundle;
    import android.os.Handler;
    import android.view.KeyEvent;
    import android.view.Menu;
    import android.view.MotionEvent;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.view.View.OnTouchListener;
    import android.widget.AdapterView;
    import android.widget.AdapterView.OnItemClickListener;
    import android.widget.AdapterView.OnItemLongClickListener;
    import android.widget.Button;
    import android.widget.EditText;
    import android.widget.GridView;
    import android.widget.ImageButton;
    import android.widget.LinearLayout;
    import android.widget.ListView;
    import android.widget.SimpleAdapter;
    import android.widget.TextView;
    import android.widget.Toast;
    
    public class MainActivity extends Activity {
    
        private LinearLayout layout;// 布局
        private GridView menuGrid;// 菜单选项
        private View menuView;// 菜单选项视图
        private Dialog menuDialog;// 菜单对话框
        private ImageButton menuBtn;// 弹出菜单
        private Integer s_id;// 记事Id;
        private TextView titleTxt;// 标题
        private Dialog delDialog;// 删除对话框
        private ImageButton addBtn;// 添加
        private ImageButton searchBtn;// 搜索
        private ListView notesList;// 记事列表
        private boolean sort;// 排序标识
        private HashMap<Integer, Integer> idMap;// 存放记事ID列表
        // 菜单选项
        final int ACTION_SAY = 0;// 感悟
        final int ACTION_HELP = 1;// 帮助
        final int ACTION_ABOUT = 2;// 关于
        final int ACTION_SORT=3;//排序
        final int ACTION_SKIN=4;//背景
        final int ACTION_EXIT = 5;// 退出
        private DatabaseManage dm = null;// 数据库管理对象
        private Cursor cursor = null;
        private int background;//背景
        private  SharedPreferences sp;//存储数据
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
    
            idMap = new HashMap<Integer, Integer>();// 获取记事ID列表
            layout = (LinearLayout) findViewById(R.id.main);
            titleTxt = (TextView) findViewById(R.id.title_main);
            addBtn = (ImageButton) findViewById(R.id.add_btn);
            menuBtn = (ImageButton) findViewById(R.id.menu_btn);
            searchBtn = (ImageButton) findViewById(R.id.search_btn);
            notesList = (ListView) findViewById(R.id.notes_lis);
            background=R.drawable.skin_first;
            getBackground();
            dm = new DatabaseManage(this);// 数据库操作对象
            sort = true; // 获取排序方式
            // 添加按钮事件监听
            ImageButton[] btns = { addBtn, searchBtn};
            for (ImageButton btn : btns)
                btn.setOnClickListener(click);
    
            // 菜单按钮
            menuBtn.setOnClickListener(new OnClickListener() {
    
                @Override
                public void onClick(View arg0) {
                    // TODO Auto-generated method stub
                    if (menuDialog == null) {
                        menuDialog = new Dialog(MainActivity.this);
                        menuDialog.show();
                    } else {
                        menuDialog.show();
                    }
                }
            });
            menuDialog = new Dialog(this, R.style.dialog); // 自定义菜单
            menuView = View.inflate(this, R.layout.gridmenu, null);
            menuDialog.setContentView(menuView);
            menuDialog.setOnKeyListener(new OnKeyListener() {//dialog的setOnKeyListener监听key手机键
                @Override
                public boolean onKey(DialogInterface dialog, int keyCode,
                                     KeyEvent event) {
                    if (keyCode == KeyEvent.KEYCODE_MENU)
                        dialog.dismiss();
                    return false;
                }
            });
            menuGrid = (GridView) menuView.findViewById(R.id.grid);
            menuGrid.setAdapter(getMenuAdapter());
            menuGrid.setOnItemClickListener(menuClick);
            // 显示记事
            showNotes(sort);
    
        }
        //设置背景
        private void getBackground(){
            sp=getSharedPreferences("backgrounds", 0);
            background=sp.getInt("background",background);
            layout.setBackgroundResource(background);
        }
        // 菜单点击事件
        private OnItemClickListener menuClick = new OnItemClickListener() {
    
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position,
                                    long id) {
                // TODO Auto-generated method stub
                switch (position) {
                    case ACTION_SAY:
                        say();
                        break;
                    case ACTION_HELP:
                        help();
                        break;
                    case ACTION_ABOUT:
                        about();
                        break;
                    case ACTION_SORT:
                        sort = !sort;
                        showNotes(sort);
                        break;
                    case ACTION_SKIN:
                        Intent intent=new Intent(MainActivity.this,Skin.class);
                        startActivity(intent);
                        finish();
                        break;
                    case ACTION_EXIT:
                        exit();
                        break;
                    default:
                        break;
                }
    
            }
            //退出
            private void exit() {
                finish();
            }
    
            // 关于
            private void about() {
                // TODO Auto-generated method stub
                Dialog aboutDialog = new Dialog(MainActivity.this, R.style.dialog);
                View aboutView = View.inflate(MainActivity.this, R.layout.about,
                        null);
                aboutDialog.setContentView(aboutView);
                aboutDialog.show();
            }
            //帮助
            private void help() {
                // TODO Auto-generated method stub
                Intent intent = new Intent(MainActivity.this, Add.class);
                Bundle data = new Bundle();
                data.putString("title",
                        getResources().getString(R.string.help_title));
                data.putString("content",
                        getResources().getString(R.string.help_content));
                intent.putExtras(data);
                startActivity(intent);
                finish();
            }
    
            // 感悟
            private void say() {
                // TODO Auto-generated method stub
                Intent intent = new Intent(MainActivity.this, Add.class);
                Bundle data = new Bundle();
                data.putString("title", getResources()
                        .getString(R.string.say_title));
                data.putString("content",
                        getResources().getString(R.string.say_content));
                intent.putExtras(data);
                startActivity(intent);
                finish();
            }
    
        };
    
        // 获取菜单列表
        private SimpleAdapter getMenuAdapter() {
            SimpleAdapter adapter = new SimpleAdapter(this, getMenu(),
                    R.layout.menuitem, new String[] { "img", "txt" }, new int[] {
                    R.id.item_img, R.id.item_txt });
            return adapter;
        }
    
        // 获取菜单
        private List<Map<String, Object>> getMenu() {
            int[] imgs = { R.drawable.say, R.drawable.help, R.drawable.about,
                    R.drawable.sort,R.drawable.skin,R.drawable.exit };
            int[] txts = { R.string.action_say, R.string.action_help,
                    R.string.action_about,R.string.action_sort,R.string.action_skin, R.string.action_exit };
            List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
            for (int i = 0; i < imgs.length; i++) {
                HashMap<String, Object> map = new HashMap<String, Object>();
                map.put("img", imgs[i]);
                map.put("txt", getResources().getString(txts[i]));
                list.add(map);
            }
            return list;
        }
    
        // 删除记事
        private void deletes() {
            View deleteView = View.inflate(this, R.layout.deletenote, null);
            delDialog = new Dialog(this, R.style.dialog);
            delDialog.setContentView(deleteView);
            Button yesBtn = (Button) deleteView.findViewById(R.id.delete_yes);
            Button noBtn = (Button) deleteView.findViewById(R.id.delete_no);
    
            yesBtn.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(View view) {
                    dm.open();
                    dm.delete(s_id);
                    Toast.makeText(MainActivity.this, R.string.note_deleted,
                            Toast.LENGTH_SHORT).show();
                    delDialog.dismiss();
                    showNotes(sort);
                }
            });
            noBtn.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(View view) {
                    delDialog.dismiss();
                }
            });
            delDialog.show();
        }
    
        // 显示记事信息
        private void showNotes(boolean model) {
            // TODO Auto-generated method stub
    
            SimpleAdapter adapter = new SimpleAdapter(MainActivity.this,
                    getData(sort), R.layout.listitem, new String[] { "id",
                    "title", "content", "time" },
                    new int[] { R.id.id, R.id.title, R.id.content, R.id.time});
            notesList.setVisibility(View.VISIBLE);
            notesList.setAdapter(adapter); // 生成记事列表
            notesList.setOnItemClickListener(listCheck);// 查看信息
            notesList.setOnItemLongClickListener(longclick);// 长按事件
    
    
        }
    
        // 点击视图的单个记事事件，查看信息
        private OnItemClickListener listCheck = new OnItemClickListener() {
    
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position,
                                    long id) {
                // TODO Auto-generated method stub
                ListView listView = (ListView) parent;
                HashMap<String, Object> map = (HashMap<String, Object>) listView
                        .getItemAtPosition(position);
                Intent intent = new Intent(MainActivity.this, Update.class);
                intent.putExtra("data", map);
                startActivity(intent);
                finish();
            }
        };
    
        // 长按事件
        public OnItemLongClickListener longclick = new OnItemLongClickListener() {
    
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view,
                                           int position, long id) {
                // TODO Auto-generated method stub
                s_id = idMap.get(position);
                deletes();
                return false;
            }
    
        };
    
        // 获取记事信息
        private List<Map<String, Object>> getData(boolean sort_desc) {
            // TODO Auto-generated method stub
            List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
            dm.open();
            cursor = dm.selectAll(sort_desc);
            int pos = 0;
            while (cursor.moveToNext()) {
                int n_id = cursor.getInt(cursor.getColumnIndex("id"));
                idMap.put(pos, n_id);
                pos += 1;
                String n_title = cursor.getString(cursor.getColumnIndex("n_title"));
                String n_content = cursor.getString(cursor
                        .getColumnIndex("n_content"));
                String n_time = cursor.getString(cursor.getColumnIndex("n_time"));
                HashMap<String, Object> map = new HashMap<String, Object>();
                map.put("id", n_id);
                map.put("title", n_title);
                map.put("content", n_content);
                map.put("time", n_time);
                list.add(map);
            }
            cursor.close();
            dm.close();
            return list;
        }
    
        // 点击事件监听
        private OnClickListener click = new OnClickListener() {
    
            @Override
            public void onClick(View v) {
                switch (v.getId()) {
                    case R.id.add_btn:
                        add_btn();
                        break;
                    case R.id.search_btn:
                        search_btn();
                        break;
                }
            }
    
            private void search_btn() {
                // TODO Auto-generated method stub
                Intent intent = new Intent(MainActivity.this, Search.class);
                startActivity(intent);
                finish();
            }
    
            private void add_btn() {
                // TODO Auto-generated method stub
                Intent intent = new Intent(MainActivity.this, Add.class);
                if (getIntent().hasExtra("title"))
                    intent.putExtras(getIntent().getExtras());
                startActivity(intent);
                finish();
            }
        };
    
        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            return true;
        }
    
    }

用到的布局：setContentView(R.layout.activity\_main)-->activity\_main.xml

menuGrid = (GridView) menuView.findViewById(R.id.grid)-->gridmenu.xml

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
            android:orientation="vertical"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:gravity="center"
            android:background="@color/transparent">
    <GridView
           android:id="@+id/grid"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:numColumns="3"
                    android:stretchMode="columnWidth"
                    android:verticalSpacing="10dip"
                    android:horizontalSpacing="2dip"
                    android:gravity="center"
                    android:background="@color/transparent" >
    </GridView>
    </LinearLayout>

menuDialog = new Dialog(this, R.style.dialog); // 自定义菜单

# 注：源码下载：[https://download.csdn.net/download/weixin\_39220472/10426057][https_download.csdn.net_download_weixin_39220472_10426057] #

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[https_download.csdn.net_download_weixin_39220472_10426057]: https://download.csdn.net/download/weixin_39220472/10426057