android 应用 源代码——备忘录

package com.fit.memo; import java.util.ArrayList; import java.util.HashMap; import android.app.ListActivity; import android.content.Context; import android.content.Intent; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.os.Bundle; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.widget.AdapterView; import android.widget.ListView; import android.widget.SimpleAdapter; import android.widget.TextView; import android.widget.Toast; import android.widget.AdapterView.OnItemClickListener; import android.widget.AdapterView.OnItemSelectedListener; import com.fit.entity.Memo; public class MainActivity extends ListActivity { private SQLiteDatabase db; private String memoId; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); } @Override protected void onStart() { query(); super.onStart(); } @Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater flater=getMenuInflater(); flater.inflate(R.menu.menu1, menu); return super.onCreateOptionsMenu(menu); } @Override public boolean onMenuItemSelected(int featureId, MenuItem item) { int menuId=item.getItemId(); switch(menuId){ //打开 case R.id.news: Intent intent=new Intent(MainActivity.this,Activity1.class); startActivity(intent); break; case R.id.open: if(memoId!=null){ Cursor cursor=db.query(Memo.TABLENAME,new String[]{Memo.CONTENT},Memo._ID+"=?",new String[]{memoId},null, null, null); if(cursor.moveToNext()){ String upContent=cursor.getString(cursor.getColumnIndex(Memo.CONTENT)); Bundle extras=new Bundle(); extras.putString("upContent",upContent); extras.putString("memoId", memoId); Intent intent2=new Intent(MainActivity.this,Activity1.class); intent2.putExtras(extras); startActivity(intent2); } }else{ Toast.makeText(MainActivity.this, "请选择要打开的记录！！", Toast.LENGTH_LONG).show(); } break; //删除 case R.id.delete: if(memoId!=null){ db.delete(Memo.TABLENAME,Memo._ID+"=?",new String[]{memoId}); Toast.makeText(MainActivity.this, "删除成功！！", Toast.LENGTH_LONG).show(); query(); }else{ Toast.makeText(MainActivity.this, "无此记录！！", Toast.LENGTH_LONG).show(); } break; } return super.onMenuItemSelected(featureId, item); } public void query(){ db=openOrCreateDatabase(Memo.DBNAME,Context.MODE_PRIVATE,null); int version=db.getVersion(); if(version<1){ db.execSQL("create table "+Memo.TABLENAME+"("+Memo._ID+" integer primary key,"+Memo.LTIME+" text,"+Memo.CONTENT+" text)"); db.setVersion(1); Toast.makeText(MainActivity.this,"数据库创建成功！！",Toast.LENGTH_LONG).show(); } Cursor cursor=db.query(Memo.TABLENAME,new String[]{Memo._ID,Memo.LTIME}, null,null,null,null,null); ArrayList<HashMap<String,String>> list=new ArrayList<HashMap<String,String>>(); while(cursor.moveToNext()){ HashMap<String,String> map=new HashMap<String, String>(); String memoId=cursor.getString(cursor.getColumnIndex(Memo._ID)); String memoLtime=cursor.getString(cursor.getColumnIndex(Memo.LTIME)); map.put("memoId",memoId); map.put("memoLtime",memoLtime); list.add(map); } SimpleAdapter adapter=new SimpleAdapter(MainActivity.this,list,R.layout.lsit,new String[]{"memoId","memoLtime"},new int[]{R.id.ids,R.id.ltime}); setListAdapter(adapter); ListView lv=getListView(); lv.setOnItemSelectedListener(new OnItemSelectedListener() { @Override public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) { TextView textId=(TextView) findViewById(R.id.ids); memoId=textId.getText().toString(); } @Override public void onNothingSelected(AdapterView<?> arg0) { } }); //点击视图事件 lv.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) { TextView textId=(TextView)arg1.findViewById(R.id.ids); memoId=textId.getText().toString(); Cursor cursor=db.query(Memo.TABLENAME,new String[]{Memo.CONTENT},Memo._ID+"=?",new String[]{memoId},null,null,null); if(cursor.moveToNext()){ String content=cursor.getString(cursor.getColumnIndex(Memo.CONTENT)); System.out.println("+++++++"+content); Bundle extras=new Bundle(); extras.putString("upContent",content); extras.putString("memoId",memoId); Intent intent=new Intent(MainActivity.this,Activity1.class); intent.putExtras(extras); startActivity(intent); } } }); } }