Android Learning (10) SQLite operation based on built-in functions

Main.xml

<LinearLayoutxmlns:android= "Http://schemas.android.com/apk/res/android"Xmlns:tools= "Http://schemas.android.com/tools"Android:layout_width= "Match_parent"Android:layout_height= "Match_parent"android:orientation= "vertical"Tools:context=". Mainactivity " >    <ButtonAndroid:id= "@+id/button1"Android:layout_width= "Match_parent"Android:layout_height= "Wrap_content"Android:text= "Insert Data" />    <ButtonAndroid:id= "@+id/button2"Android:layout_width= "Match_parent"Android:layout_height= "Wrap_content"Android:text= "Read Data" />    <ButtonAndroid:id= "@+id/button3"Android:layout_width= "Match_parent"Android:layout_height= "Wrap_content"Android:text= "Modify Data" />    <ButtonAndroid:id= "@+id/button4"Android:layout_width= "Match_parent"Android:layout_height= "Wrap_content"Android:text= "Delete Data" /></LinearLayout>

Main.java

 PackageCom.example.sqlitedemo2;Importandroid.app.Activity;Importandroid.content.ContentValues;ImportAndroid.database.Cursor;Importandroid.database.sqlite.SQLiteDatabase;ImportAndroid.os.Bundle;ImportAndroid.util.Log;ImportAndroid.view.View;ImportAndroid.view.View.OnClickListener;ImportAndroid.widget.Button;ImportAndroid.widget.Toast; Public classMainactivityextendsActivity {Button btn1;    Button btn2;    Button Btn3;    Button Btn4;    Sqlitedatabase DB; @Overrideprotected voidonCreate (Bundle savedinstancestate) {Super. OnCreate (savedinstancestate);        Setcontentview (R.layout.activity_main); DB= Openorcreatedatabase ("Stu.db", Mode_private,NULL); Db.execsql ("CREATE table if not exists Tb_user (ID integer primary key autoincrement,name text not null,age integer not null,sex text NOT null) "); BTN1=(Button) Findviewbyid (R.id.button1); BTN2=(Button) Findviewbyid (R.id.button2); Btn3=(Button) Findviewbyid (R.id.button3); Btn4=(Button) Findviewbyid (R.ID.BUTTON4); Btn1.setonclicklistener (NewOnclicklistener () {@Override Public voidOnClick (View v) {contentvalues values=Newcontentvalues (); Values.put ("Name", "John Doe"); Values.put ("Age", 20); Values.put ("Sex", "female"); Db.insert ("Tb_user",NULL, values);                                Values.clear (); Values.put ("Name", "Harry"); Values.put ("Age", 22); Values.put ("Sex", "male"); Db.insert ("Tb_user",NULL, values); Toast.maketext (mainactivity. This, "Add Success", 1). Show ();        }        }); Btn2.setonclicklistener (NewOnclicklistener () {@Override Public voidOnClick (View v) {Cursor cur= Db.query ("Tb_user",Newstring[]{"Name", "Age", "Sex"},NULL,NULL,NULL,NULL,NULL);  while(Cur.movetonext ()) {String name= Cur.getstring (Cur.getcolumnindex ("name")); intAge = Cur.getint (The Cur.getcolumnindex ("Age")); String Sex= Cur.getstring (Cur.getcolumnindex ("Sex"))); LOG.I ("Stuinfo", Name + "," + Age + "," +sex);            } cur.close ();                        }                    }); Btn3.setonclicklistener (NewOnclicklistener () {@Override Public voidOnClick (View v) {//Modifying DataContentvalues values =Newcontentvalues (); Values.put ("Name", "Zhang San Fung"); intresult = Db.update ("Tb_user", Values, "id=?",Newstring[]{"1"}); if(Result > 0) Toast.maketext (mainactivity. This, "modified successfully", 1). Show (); ElseToast.maketext (mainactivity. This, "Modification failed", 1). Show ();                }        }); Btn4.setonclicklistener (NewOnclicklistener () {@Override Public voidOnClick (View v) {//Delete Data                intresult = Db.delete ("Tb_user", "id=?",Newstring[]{"1"}); if(Result > 0) Toast.maketext (mainactivity. This, "Delete succeeded", 1). Show (); ElseToast.maketext (mainactivity. This, "Delete Failed", 1). Show ();    }        }); }}

Android Learning (10) SQLite operation based on built-in functions