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自己写的一个简单的记事本app，效果如下：
一、首先是第一个界面的编写，最上面是一个textview，中间是一个linearlayout中嵌套一个listview布局，最下面是一个button。下面附上第一个页面的简单布局xml文件。
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="@android:color/darker_gray" android:orientation="vertical" > <textview android:layout_height="wrap_content" android:layout_width="fill_parent" android:text="记事本列表" android:textsize="20sp" android:paddingtop="10dp" android:paddingbottom="5dp" android:background="#039dcf" android:gravity="center"/> <linearlayout android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="1" > <listview android:id="@+id/listview" android:layout_margin="5dp" android:background="#81966f" android:layout_width="match_parent" android:layout_height="wrap_content" > </listview> </linearlayout> <button android:id="@+id/btn_editnote" android:layout_width="fill_parent" android:layout_height="wrap_content" android:background="@drawable/btn_selctor" android:layout_gravity="center" android:layout_marginbottom="10dp" android:text="添加备忘录" android:textsize="20sp" /> </linearlayout>
至于button的样式btn_selector就是自己定义的button样式。
二、其次就是设置listview中数据显示的xml文件，代码如下：
<?xml version="1.0" encoding="utf-8"?> <linearlayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <textview android:id="@+id/tv_content" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginleft="10dp" android:singleline="true" android:text="large text" android:textappearance="?android:attr/textappearancelarge" /> <textview android:id="@+id/tv_date" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginleft="10dp" android:text="textview" /> </linearlayout>
三、编写第二个界面样式，第二个界面是最上面一个linearlayout，里面包含两个button和一个textview。代码如下：
<?xml version="1.0" encoding="utf-8"?> <linearlayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:background="#ffae99" android:orientation="vertical" > <linearlayout android:layout_width="match_parent" android:layout_height="wrap_content" > <button android:id="@+id/btn_cancel" android:layout_width="wrap_content" android:layout_height="wrap_content" android:background="@drawable/btn_selctor" android:text="取消" /> <linearlayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" android:layout_weight="1" android:orientation="vertical" > <textview android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="center" android:text="编辑备忘录" android:textsize="20sp" /> <textview android:id="@+id/tv_date" android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="center" android:text="" /> </linearlayout> <button android:id="@+id/btn_ok" android:layout_width="wrap_content" android:layout_height="wrap_content" android:background="@drawable/btn_selctor" android:text="保存" /> </linearlayout> <scrollview android:layout_width="fill_parent" android:layout_height="fill_parent" android:scrollbars="vertical" > <linearlayout android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_marginleft="2dp" android:orientation="vertical" > <edittext android:id="@+id/et_content" android:layout_width="fill_parent" android:layout_height="wrap_content" android:background="#ffae99" android:textsize="20sp" /> </linearlayout> </scrollview> </linearlayout>
四、将日志的数据保存在数据库中，使用sqlite来创建数据库，数据库中有三个属性，"_id"、"content"、"date"这三个属性，创建一个notedb来创建数据库。
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package com.example.datenote;
import android.content.context;
import android.database.sqlite.sqlitedatabase;
import android.database.sqlite.sqliteopenhelper;
import android.util.log;
public class notesdb extends sqliteopenhelper {
public static final string table_name_notes = "note";
public static final string column_name_id = "_id";
public static final string column_name_note_content = "content";
public static final string column_name_note_date = "date";
public notesdb(context context) {
super(context, "note", null, 1);
// todo auto-generated constructor stub
}
@override
public void oncreate(sqlitedatabase db) {
string sql = "create table " + table_name_notes + "(" + column_name_id
+ " integer primary key autoincrement,"
+ column_name_note_content + " text not null default\"\","
+ column_name_note_date + " text not null default\"\"" + ")";
log.d("sql", sql);
db.execsql(sql);
// string sql1="insert into "+table_name_notes+"values("+"1,"+"'写作业',"+"'晚上要写作业的干活'"+")";
// log.d("sql1", sql1);
// db.execsql(sql1);
// contentvalues values=new contentvalues();
// values.put("id",1);
// values.put("content","写作业");
// values.put("date", "2013-1-2");
// db.insert("note", null, values);
}
@override
public void onupgrade(sqlitedatabase arg0, int arg1, int arg2) {
// todo auto-generated method stub
}
}
五、实现点击添加事件的跳转,在第一个页面中点击添加备忘录后会跳转到第二个界面，设置点击事件，由一个activity跳转到另外一个activity，我使用的是intent方式。另外，在listview中点击每个已记录下来的日志也会跳转到第二个界面，只是显示的不是空白的edittext，而是包含日志的edittext。mainactivity如下：
package com.example.datenote;
import java.util.arraylist;
import java.util.hashmap;
import java.util.list;
import java.util.map;
import android.app.activity;
import android.app.alertdialog;
import android.app.alertdialog.builder;
import android.content.context;
import android.content.dialoginterface;
import android.content.intent;
import android.database.cursor;
import android.database.sqlite.sqlitedatabase;
import android.os.bundle;
import android.util.log;
import android.view.view;
import android.view.view.onclicklistener;
import android.view.window;
import android.widget.abslistview;
import android.widget.abslistview.onscrolllistener;
import android.widget.adapterview;
import android.widget.adapterview.onitemclicklistener;
import android.widget.adapterview.onitemlongclicklistener;
import android.widget.button;
import android.widget.listview;
import android.widget.simpleadapter;
import android.widget.textview;
import android.widget.toast;
public class mainactivity extends activity implements onscrolllistener,
onitemclicklistener, onitemlongclicklistener {
private context mcontext;
private listview listview;
private simpleadapter simp_adapter;
private list<map<string, object>> datalist;
private button addnote;
private textview tv_content;
private notesdb db;
private sqlitedatabase dbread;
@override
protected void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
requestwindowfeature(window.feature_no_title);
setcontentview(r.layout.activity_main);
tv_content = (textview) findviewbyid(r.id.tv_content);
listview = (listview) findviewbyid(r.id.listview);
datalist = new arraylist<map<string, object>>();
addnote = (button) findviewbyid(r.id.btn_editnote);
mcontext = this;
addnote.setonclicklistener(new onclicklistener() {
@override
public void onclick(view arg0) {
noteedit.enter_state = 0;
intent intent = new intent(mcontext, noteedit.class);
bundle bundle = new bundle();
bundle.putstring("info", "");
intent.putextras(bundle);
startactivityforresult(intent, 1);
}
});
db = new notesdb(this);
dbread = db.getreadabledatabase();
// 清空数据库中表的内容
//dbread.execsql("delete from note");
refreshnoteslist();
listview.setonitemclicklistener(this);
listview.setonitemlongclicklistener(this);
listview.setonscrolllistener(this);
}
public void refreshnoteslist() {
int size = datalist.size();
if (size > 0) {
datalist.removeall(datalist);
simp_adapter.notifydatasetchanged();
listview.setadapter(simp_adapter);
}
simp_adapter = new simpleadapter(this, getdata(), r.layout.item,
new string[] { "tv_content", "tv_date" }, new int[] {
r.id.tv_content, r.id.tv_date });
listview.setadapter(simp_adapter);
}
private list<map<string, object>> getdata() {
cursor cursor = dbread.query("note", null, "content!=\"\"", null, null,
null, null);
while (cursor.movetonext()) {
string name = cursor.getstring(cursor.getcolumnindex("content"));
string date = cursor.getstring(cursor.getcolumnindex("date"));
map<string, object> map = new hashmap<string, object>();
map.put("tv_content", name);
map.put("tv_date", date);
datalist.add(map);
}
cursor.close();
return datalist;
}
@override
public void onscroll(abslistview arg0, int arg1, int arg2, int arg3) {
// todo auto-generated method stub
}
// 滑动listview监听事件
@override
public void onscrollstatechanged(abslistview arg0, int arg1) {
// todo auto-generated method stub
switch (arg1) {
case scroll_state_fling:
log.i("main", "用户在手指离开屏幕之前，由于用力的滑了一下，视图能依靠惯性继续滑动");
case scroll_state_idle:
log.i("main", "视图已经停止滑动");
case scroll_state_touch_scroll:
log.i("main", "手指没有离开屏幕，试图正在滑动");
}
}
// 点击listview中某一项的监听事件
@override
public void onitemclick(adapterview<?> arg0, view arg1, int arg2, long arg3) {
noteedit.enter_state = 1;
// log.d("arg2", arg2 + "");
// textview
// content=(textview)listview.getchildat(arg2).findviewbyid(r.id.tv_content);
// string content1=content.tostring();
string content = listview.getitematposition(arg2) + "";
string content1 = content.substring(content.indexof("=") + 1,
content.indexof(","));
log.d("content", content1);
cursor c = dbread.query("note", null,
"content=" + "'" + content1 + "'", null, null, null, null);
while (c.movetonext()) {
string no = c.getstring(c.getcolumnindex("_id"));
log.d("text", no);
// intent intent = new intent(mcontext, noteedit.class);
// intent.putextra("data", text);
// setresult(4, intent);
// // intent.putextra("data",text);
// startactivityforresult(intent, 3);
intent myintent = new intent();
bundle bundle = new bundle();
bundle.putstring("info", content1);
noteedit.id = integer.parseint(no);
myintent.putextras(bundle);
myintent.setclass(mainactivity.this, noteedit.class);
startactivityforresult(myintent, 1);
}
}
@override
// 接受上一个页面返回的数据，并刷新页面
protected void onactivityresult(int requestcode, int resultcode, intent data) {
// todo auto-generated method stub
super.onactivityresult(requestcode, resultcode, data);
if (requestcode == 1 && resultcode == 2) {
refreshnoteslist();
}
}
// 点击listview中某一项长时间的点击事件
@override
public boolean onitemlongclick(adapterview<?> arg0, view arg1, int arg2,
long arg3) {
final int n=arg2;
builder builder = new alertdialog.builder(this);
builder.settitle("删除该日志");
builder.setmessage("确认删除吗？");
builder.setpositivebutton("确定", new dialoginterface.onclicklistener() {
@override
public void onclick(dialoginterface dialog, int which) {
string content = listview.getitematposition(n) + "";
string content1 = content.substring(content.indexof("=") + 1,
content.indexof(","));
cursor c = dbread.query("note", null, "content=" + "'"
+ content1 + "'", null, null, null, null);
while (c.movetonext()) {
string id = c.getstring(c.getcolumnindex("_id"));
string sql_del = "update note set content='' where _id="
+ id;
dbread.execsql(sql_del);
refreshnoteslist();
}
}
});
builder.setnegativebutton("取消", new dialoginterface.onclicklistener() {
@override
public void onclick(dialoginterface dialog, int which) {
}
});
builder.create();
builder.show();
return true;
}
}
六、编写第二个跳转后界面的activity，如下：
package com.example.datenote;
import java.text.simpledateformat;
import java.util.date;
import android.app.activity;
import android.content.context;
import android.content.intent;
import android.database.sqlite.sqlitedatabase;
import android.database.sqlite.sqlitestatement;
import android.os.bundle;
import android.util.log;
import android.view.view;
import android.view.view.onclicklistener;
import android.view.window;
import android.view.windowmanager;
import android.view.inputmethod.inputmethodmanager;
import android.widget.button;
import android.widget.edittext;
import android.widget.textview;
public class noteedit extends activity {
private textview tv_date;
private edittext et_content;
private button btn_ok;
private button btn_cancel;
private notesdb db;
private sqlitedatabase dbread;
public static int enter_state = 0;
public static string last_content;
public static int id;
@override
protected void oncreate(bundle savedinstancestate) {
// todo auto-generated method stub
super.oncreate(savedinstancestate);
// 设置无标题
requestwindowfeature(window.feature_no_title);
setcontentview(r.layout.edit);
tv_date = (textview) findviewbyid(r.id.tv_date);
date date = new date();
simpledateformat sdf = new simpledateformat("yyyy-mm-dd hh:mm");
string datestring = sdf.format(date);
tv_date.settext(datestring);
et_content = (edittext) findviewbyid(r.id.et_content);
// 设置软键盘自动弹出
getwindow().setsoftinputmode(
windowmanager.layoutparams.soft_input_state_always_visible);
db = new notesdb(this);
dbread = db.getreadabledatabase();
bundle mybundle = this.getintent().getextras();
last_content = mybundle.getstring("info");
log.d("last_content", last_content);
et_content.settext(last_content);
// 确认按钮的点击事件
btn_ok = (button) findviewbyid(r.id.btn_ok);
btn_ok.setonclicklistener(new onclicklistener() {
public void onclick(view arg0) {
// 获取日志内容
string content = et_content.gettext().tostring();
log.d("log1", content);
// 获取写日志时间
date date = new date();
simpledateformat sdf = new simpledateformat("yyyy-mm-dd");
string datenum = sdf.format(date);
string sql;
string sql_count = "select count(*) from note";
sqlitestatement statement = dbread.compilestatement(sql_count);
long count = statement.simplequeryforlong();
log.d("count", count + "");
log.d("enter_state", enter_state + "");
// 添加一个新的日志
if (enter_state == 0) {
if (!content.equals("")) {
sql = "insert into " + notesdb.table_name_notes
+ " values(" + count + "," + "'" + content
+ "'" + "," + "'" + datenum + "')";
log.d("log", sql);
dbread.execsql(sql);
}
}
// 查看并修改一个已有的日志
else {
log.d("执行命令", "执行了该函数");
string updatesql = "update note set content='"
+ content + "' where _id=" + id;
dbread.execsql(updatesql);
// et_content.settext(last_content);
}
intent data = new intent();
setresult(2, data);
finish();
}
});
btn_cancel = (button) findviewbyid(r.id.btn_cancel);
btn_cancel.setonclicklistener(new onclicklistener() {
public void onclick(view arg0) {
finish();
}
});
}
@override
protected void onactivityresult(int requestcode, int resultcode, intent data) {
// todo auto-generated method stub
super.onactivityresult(requestcode, resultcode, data);
// if (requestcode == 3 && resultcode == 4) {
// last_content=data.getstringextra("data");
// log.d("last_straing", last_content+"gvg");
// }
}
}
七、其中，对listview添加onitemlongclicklistener，长点击之后会弹出一个dialog对话框提醒要不要删除该日志文件。
public boolean onitemlongclick(adapterview<?> arg0, view arg1, int arg2,
long arg3) {
final int n=arg2;
builder builder = new alertdialog.builder(this);
builder.settitle("删除该日志");
builder.setmessage("确认删除吗？");
builder.setpositivebutton("确定", new dialoginterface.onclicklistener() {
@override
public void onclick(dialoginterface dialog, int which) {
string content = listview.getitematposition(n) + "";
string content1 = content.substring(content.indexof("=") + 1,
content.indexof(","));
cursor c = dbread.query("note", null, "content=" + "'"
+ content1 + "'", null, null, null, null);
while (c.movetonext()) {
string id = c.getstring(c.getcolumnindex("_id"));
string sql_del = "update note set content='' where _id="
+ id;
dbread.execsql(sql_del);
refreshnoteslist();
}
}
});
builder.setnegativebutton("取消", new dialoginterface.onclicklistener() {
@override
public void onclick(dialoginterface dialog, int which) {
}
});
builder.create();
builder.show();
return true;
}
注意最后将返回值设为true，否则会和onitemclicklistener产生冲突。
附上长点击删除的效果。
在结尾附上自己的代码，自己辛苦写的，收取一个资源不多吧，感兴趣的可以下载看看。
下载
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