Android Studio 的NotePad制作（日志本）

自己写的NotePad，一个星期左右的时间。完成了最基本的功能。
但是 界面还是一如既往的shi（因为百度找的图标都不是那种成套的，想找的找不到，干脆下次自己画！）
NotePad的功能无非是对日志的增删改查，这次还加入了Preference的一些配置的设置。
这是主界面，上方的都是已经建好的日志。
下面的数字和图标对应xml控件的功能为：
①：已经写好的日志的个数
②：系统设置
③：新建日志
④：查找
⑤：锁定界面

先从日志本的数据库讲，基础的数据为日志ID，日志标题，日志内容，日志创建时间。
其次为主题颜色的int值，包括橙色、天蓝、红色等等。
接下来是各种xml布局，基本大同小异，自己想怎么弄就怎么弄。
设置了两个存数据的类，一个是NoteVO为存放ID，Title等关于日志的数据，并写了一个DBAccess里面运用SQL的语法对数据库进行增删改查；还有一个是PrefVO，里面存放了用户的密码以及主题颜色、一些设置保存密码的东西。

为日志本设置了密码，默认密码为空，在设置里面可以进行密码的修改。
设置密码之后，用户可以进行app锁定，下次进来后也要用密码解锁。
主界面为 NotePadMainActivity
除了对图标设置监听事件，比较重要的是 重写 onResum，即刷新界面还有判断此时页面是否锁住，这里写了一个框框加载，代码如下：

 protected void onResume() {
        super.onResume();
       showProgressDialog();

       //判断用户是否上锁，如果上锁，弹出对话框提示用户输入密码
        if(PrefVO.ifLocked){
            final EditText keytext = new EditText(NotePadMainActivity.this);
            keytext.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);

            AlertDialog.Builder builder = new AlertDialog.Builder(NotePadMainActivity.this);
            builder.setTitle("请输入密码");
            builder.setIcon(R.drawable.suo);
            builder.setView(keytext);
            builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {

                    if(PrefVO.userPasswordValue.equals(keytext.getText().toString())){
                        PrefVO.appLock(false);
                        Toast.makeText(NotePadMainActivity.this,"已解除锁定",Toast.LENGTH_LONG).show();
                    }
                    else {
                        Toast.makeText(NotePadMainActivity.this,"密码错误",Toast.LENGTH_LONG).show();
                        NotePadMainActivity.this.finish();
                    }
                }
            });
            builder.setOnCancelListener(new DialogInterface.OnCancelListener() {
                @Override
                public void onCancel(DialogInterface dialog) {
                    NotePadMainActivity.this.finish();
                }
            });
            builder.create().show();
        }
    }
 //刷新界面
    private void flush() {
        PrefVO.dataFlush();


        noteVOList = access.findAllNote();
        noteBaseAdapter = new NoteBaseAdapter(NotePadMainActivity.this, R.layout.item, noteVOList);
        noteList.setAdapter(noteBaseAdapter);
        noteNumText.setText(noteVOList.size() + "");
    }





    private class OnItemSelectedListener implements AdapterView.OnItemClickListener {
        @Override
        public void onItemClick(AdapterView parent, View view, int position, long id) {
            note = noteVOList.get(position);

            Intent intent = new Intent();
            intent.setClass(NotePadMainActivity.this, NotePadScanActivity.class);

            Bundle bundle = new Bundle();
            bundle.putParcelable("note", note);
            intent.putExtra("noteBundle", bundle);

            NotePadMainActivity.this.startActivity(intent);
        }
    }


    private void showProgressDialog() {
        pgDialog.setTitle("loading....");
        pgDialog.setMessage("少女祈祷中.....");
        pgDialog.show();
        new progressThread().start();
    }

    private Handler handler = new Handler(){
        public void handleMessage(Message msg){
            flush();
            pgDialog.cancel();
        }
    };

    private class progressThread extends Thread{

        @Override
        public void run() {
            try{
                   Thread.sleep(1000);
                   handler.sendEmptyMessage(1);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

这里对列表日志设置了一个长按选项，长按后出现删除和短信发送的提示。
代码如下：

public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo){
        super.onCreateContextMenu(menu,v,menuInfo);

        menu.setHeaderIcon(R.drawable.shezhi);
        menu.setHeaderTitle("日志选项");
        menu.add(0,1,1,"删除");
        menu.add(0,2,2,"短信发送");

    }



    public boolean onContextItemSelected(MenuItem item){
        AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
        int index = info.position;
        final NoteVO note = noteVOList.get(index);
        switch (item.getItemId()){
            case 1:{
                AlertDialog.Builder builder = new AlertDialog.Builder(NotePadMainActivity.this);
                builder.setTitle("删除");
                builder.setIcon(R.drawable.shanchu);
                builder.setMessage("你确定要把日志删除吗？");
                builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        DBAccess access = new DBAccess(NotePadMainActivity.this);
                        access.deleteNote(note);
                        dialog.dismiss();
                        Toast.makeText(NotePadMainActivity.this,"已删除",Toast.LENGTH_LONG).show();
                        flush();
                    }
                });
                builder.setNegativeButton("取消",null);
                builder.create().show();
                break;
            }
            case 2:{
                Intent intent = new Intent(Intent.ACTION_SENDTO, Uri.parse("smsto:"));

                if(!note.getNoteContent().equals(note.getNoteTitle())){
                    intent.putExtra("sms_body",note.getNoteContent() + "\n" + note.getNoteTitle());
                }
                else intent.putExtra("sms_body",note.getNoteContent());
                NotePadMainActivity.this.startActivity(intent);

                break;
            }
        }
        return super.onContextItemSelected(item);
    }

此为点击设置之后的界面

设置颜色的代码如下：

 themeList = (ListPreference) findPreference("themelist");
        themeList.setSummary(PrefVO.themeListValue);
        themeList.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
            @Override
            public boolean onPreferenceChange(Preference preference, Object newValue) {
                String value = (String)newValue;
                themeList.setSummary(value);
                PrefVO.setThemeListValue(value);

                return true;
            }
        });

设置密码的话，因为我已经设置过了，所以有显示为旧密码，如果第一次设置密码，他只有输入密码和确认密码，两个dialog代码如下:

builder_1 = new AlertDialog.Builder(NotePadPreferenceActivity.this);
        builder_1.setView(linearLayout_1);
        builder_1.setTitle("设置新密码");
        builder_1.setIcon(R.drawable.suo);
        builder_1.setPositiveButton("确定", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                String key = newkeyyext.getText().toString();
                String keyagain = newkeyagaintext.getText().toString();

                if(key.equals("") || keyagain.equals("")){
                    Toast.makeText(NotePadPreferenceActivity.this,"密码不能为空",Toast.LENGTH_LONG).show();
                }
                else if(key.equals(keyagain)){
                    PrefVO.setUserPasswordValue(key);
                    usersafety.setTitle("修改密码" );
                }
                else if(!key.equals(keyagain)){
                    Toast.makeText(NotePadPreferenceActivity.this,"两次密码不一致",Toast.LENGTH_LONG).show();
                }
                dialog_1.dismiss();
                clearText();
            }
        });

        builder_1.setNegativeButton("取消", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog_1.dismiss();
                clearText();
            }
        });

        dialog_1 = builder_1.create();

        builder_2 = new AlertDialog.Builder(NotePadPreferenceActivity.this);
        builder_2.setView(linearLayout_2);
        builder_2.setIcon(R.drawable.suo);
        builder_2.setPositiveButton("确定", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                String oldkey = oldkeytext.getText().toString();
                String modifykey = modifykeytext.getText().toString();
                String modifyagainkey = modifykeyagaintext.getText().toString();

                if(!oldkey.equals(PrefVO.userPasswordValue)){
                    Toast.makeText(NotePadPreferenceActivity.this,"密码错误",Toast.LENGTH_LONG).show();
                }
                else if(modifykey.equals("")){
                    Toast.makeText(NotePadPreferenceActivity.this,"密码不能为空",Toast.LENGTH_LONG).show();
                }
                else if(!modifyagainkey.equals(modifyagainkey)){
                    Toast.makeText(NotePadPreferenceActivity.this,"两次输入密码不正确",Toast.LENGTH_LONG).show();
                }
                else if(modifykey.equals(modifyagainkey)){
                    PrefVO.setUserPasswordValue(modifykey);
                }
                dialog_2.dismiss();
                clearText();
            }
        });
        builder_2.setNegativeButton("取消", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog_2.dismiss();
                clearText();
            }
        });
        dialog_2 = builder_2.create();

        //定义的密码为“”，所以根据密码来判断是第一次设置密码还是修改密码
        usersafety = findPreference("usersafety");
        if(PrefVO.userPasswordValue.equals("")){
            usersafety.setTitle("设置新密码");
        }
        else {
            usersafety.setTitle("修改密码");
        }
        usersafety.setOnPreferenceClickListener(new Preference.OnPreferenceClickListener() {
            @Override
            public boolean onPreferenceClick(Preference preference) {
                if(PrefVO.userPasswordValue.equals(""))
                    dialog_1.show();
                else
                    dialog_2.show();
                return false;
            }
        });
    }

    //此方法清空editview，同时要将光标聚焦到第一个EditView
    private void clearText() {
        newkeyyext.setText("");
        newkeyagaintext.setText("");
        newkeyyext.requestFocus();

        oldkeytext.setText("");
        modifykeytext.setText("");
        modifykeyagaintext.setText("");
        oldkeytext.requestFocus();
    }

接下来为新建日志本，这里自己写了两个分别继承TextView和EditView的子控件：NoteTextView，NoteEditView，做了少许的更改。
进入新建页面后，会将焦点放在content上，然后标题跟随打印内容，直到用户自己想写一个标题的时候。在按下返回键后，重写onBackPressed，将新写的日志内容存入到数据库，页面来到查看页面，Toast打印已保存。
[外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-O8cF2dQW-1587976591599)(//img-blog.csdn.net/20180314120118935?watermark/2/text/Ly9ibG9nLmNzZG4ubmV0L3Jpa2thdGhld29ybGQ=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70)]
实现代码如下：

protected void onCreate(Bundle saveInstanceState) {
        super.onCreate(saveInstanceState);
        setContentView(R.layout.edit);
        editLayout = findViewById(R.id.editlayout);
        editLayout.setBackgroundColor(PrefVO.themeColorValue);

        noteTitleText = findViewById(R.id.titleedit);
        noteContentText = findViewById(R.id.contentedit);
        noteContentText.requestFocus();
        noteContentText.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
                if(flagTextChanged && (noteTitleText.getText().toString().trim().equals(null) ||
                noteTitleText.getText().toString().trim().equals(""))){
                    flagTextChanged = true;
                }
                else if(!noteTitleText.getText().toString().equals(noteContentText.getText().toString()))
                    flagTextChanged = false;
            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
                 if(flagTextChanged)
                     noteTitleText.setText(noteContentText.getText());
            }

            @Override
            public void afterTextChanged(Editable s) {

            }
        });
    }

    public void onBackPressed(){
        super.onBackPressed();

        String noteTitle = noteTitleText.getText().toString();
        String noteContent = noteContentText.getText().toString();

        if (noteTitle.toString().trim().equals("") && noteContent.toString().trim().equals(""))
            NotePadNewActivity.this.finish();
        else{
            NoteVO note = new NoteVO();
            note.setNoteTitle(noteTitle);
            note.setNoteContent(noteContent);
            note.setNoteDate(new Date());

            DBAccess access = new DBAccess(this);
            access.insertNote(note);

            Toast.makeText(this,"已保存",Toast.LENGTH_LONG).show();

            Intent intent = new Intent();
            intent.setClass(this,NotePadScanActivity.class);
            Bundle bundle = new Bundle();
            bundle.putParcelable("note",note);
            intent.putExtra("noteBundle",bundle);

            this.startActivity(intent);
            this.finish();
        }
    }

进入查看界面有三个可选操作：编辑，删除，短信发送。编辑即返回到edit的页面。

实现代码如下：

scanLayout = findViewById(R.id.scanlayout);
        scanLayout.setBackgroundColor(PrefVO.themeColorValue);

        noteTitleText = findViewById(R.id.titlescan);
        noteContentText = findViewById(R.id.contentscan);
        noteContentText.setMovementMethod(ScrollingMovementMethod.getInstance());
        notedateText = findViewById(R.id.datescan);

        intent = this.getIntent();
        Bundle bundle = intent.getBundleExtra("noteBundle");
        noteVO = bundle.getParcelable("note");

        noteTitleText.setText(noteVO.getNoteTitle());
        notedateText.setText(ConvertDate.datetoString(noteVO.getNoteDate()));
        noteContentText.setText(noteVO.getNoteContent());

        bianji = findViewById(R.id.bianji);
        bianji.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                Intent intent = new Intent();
                intent.setClass(NotePadScanActivity.this,NotePadEditActivity.class);

                Bundle bundle= new Bundle();
                bundle.putParcelable("note",noteVO);
                intent.putExtra("noteBundle",bundle);

                NotePadScanActivity.this.startActivity(intent);
                NotePadScanActivity.this.finish();
                return false;
            }
        });

        duanxin = findViewById(R.id.duanxin);
        duanxin.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                Intent intent = new Intent(Intent.ACTION_SENDTO, Uri.parse("smsto:"));

                if(!noteVO.getNoteContent().equals(noteVO.getNoteTitle())){
                    intent.putExtra("sms_body", noteVO.getNoteTitle() + "\n" + noteVO.getNoteContent());
                }
                else {
                    intent.putExtra("sms_body", noteVO.getNoteContent());
                }
                NotePadScanActivity.this.startActivity(intent);

                return false;
            }
        });

        shanchu = findViewById(R.id.shanchu);
        shanchu.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                AlertDialog.Builder builder = new AlertDialog.Builder(NotePadScanActivity.this);
                builder.setTitle("删除");
                builder.setIcon(R.drawable.shanchu);
                builder.setMessage("你确定要把日志删除吗？");
                builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        DBAccess access = new DBAccess(NotePadScanActivity.this);
                        access.deleteNote(noteVO);

                        dialog.dismiss();
                        Toast.makeText(NotePadScanActivity.this, "已删除", Toast.LENGTH_LONG).show();
                        NotePadScanActivity.this.finish();
                    }
                });
                builder.setNegativeButton("取消", null);
                builder.create().show();

                return false;
            }
        });

最后则是查找操作

在mainfest设置为对话框形式，写了一个NoteCursorAdapter继承CursorAdapter，对列表日志的标题和内容进行查找，用到AutoCompleteTextView代码如下：

 protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        this.setContentView(R.layout.search);

        access = new DBAccess(this);

        c = access.selectAllNoteCursor(null,null);
        noteCursorAdapter = new NoteCursorAdapter(this,c,true);
        searchTextView = findViewById(R.id.searchtext);
        searchTextView.setDropDownHeight(0);
        searchTextView.requestFocus();
        searchTextView.setAdapter(noteCursorAdapter);

        searchListView = findViewById(R.id.searchList);
        searchListView.setAdapter(noteCursorAdapter);
        searchListView.setOnItemClickListener(new OnItemSelectListener());
    }

    private class OnItemSelectListener implements AdapterView.OnItemClickListener {
        @Override
        public void onItemClick(AdapterView parent, View view, int position, long id) {
           note = noteCursorAdapter.getList().get(position);

           Intent intent = new Intent();
           intent.setClass(NotePadSearchActivity.this,NotePadScanActivity.class);

           Bundle bundle = new Bundle();
           bundle.putParcelable("note",note);
           intent.putExtra("noteBundle",bundle);

           NotePadSearchActivity.this.startActivity(intent);
        }
    }

至此为止，功能基本实现，其他的代码就不放了，等下挂GIT
emmm由于在debug的时候有很多数据库的单词填错或者没写空格，几乎浪费了一个上午的时间，还有参考的书籍实在太过老旧，menuItem在AS3.0已经不用，在那上面还是浪费了很多时间。
这次的话我注意了代码的美观，尽量让代码看起来易懂一点，虽然注释也少了一点…