public class MyHelper extends SQLiteOpenHelper {
public MyHelper(Context context,String name,SQLiteDatabase.CursorFactory factory,int version){
super(context,name,factory,version);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("create table ordertb(_id integer primary key "+"autoincrement," +
"name string not null,count integer not null,range integer not null)");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
【下方导航栏的实现】
<RelativeLayout xmlns:android="schemas.android.com/apk/res/and…"
xmlns:tools="schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<LinearLayout
android:id="@+id/linearLayout"
android:layout_width="match_parent"
android:layout_height="60dp"
android:layout_alignParentLeft="true"
android:layout_alignParentBottom="true"
android:layout_alignParentStart="true"
android:background="#E8EEF5"
android:baselineAligned="false"
tools:ignore="Orientation"
<LinearLayout
android:id="@+id/llay_guess"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:gravity="center"
android:background="#E8EEF5"
android:orientation="vertical">
<ImageView
android:id="@+id/img_guess"
android:layout_width="40dp"
android:layout_height="40dp"
android:src="@drawable/game_on"/>
<TextView
android:id="@+id/txt_guess"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/txt_guess"
android:textSize="20dp"
android:textStyle="bold"
android:textColor="@color/color_txt_pressed"/>
<LinearLayout
android:layout_width="2dp"
android:layout_height="match_parent"
android:divider="@color/color_txt_pressed"
android:showDividers="end">
<LinearLayout
android:id="@+id/llay_order"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:orientation="vertical"
android:gravity="center">
<ImageView
android:id="@+id/img_order"
android:layout_width="40dp"
android:layout_height="40dp"
android:src="@drawable/rank_off"
android:layout_gravity="center_horizontal"/>
<TextView
android:id="@+id/txt_order"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/txt_order"
android:textSize="20dp"
android:textStyle="bold"
android:textColor="@color/color_txt_normal"/>
<LinearLayout
android:id="@+id/llay_setting"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:orientation="vertical"
android:gravity="center">
<ImageView
android:id="@+id/img_setting"
android:layout_width="40dp"
android:layout_height="40dp"
android:src="@drawable/setting_off"/>
<TextView
android:id="@+id/txt_setting"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/txt_setting"
android:textSize="20dp"
android:textStyle="bold"
android:textColor="@color/color_txt_normal"/>
<FrameLayout
android:id="@+id/fragment_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="@id/linearLayout"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"/>
布局中涉及的“strings.xml”文件如下：
猜数
排行榜
设置
布局中涉及的“colors.xml”文件如下：
#737373
#d4257b
在MainActivity中实现导航逻辑之前，先搭个基本页面框架：
新建GuessFragment（猜数字页）、OrderFragment（积分排行榜页）和SettingFragment（设置页）3个类，以及对应的布局文件“fragment_guess.xml”、“fragment_order.xml”和“fragment_setting.xml”。
在MainActivity中的代码如下：
package com.example.mygame;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
private LinearLayout ILay_guess,ILay_order,ILay_setting;
private ImageView img_guess,img_order,img_setting;
private TextView txt_guess,txt_order,txt_setting;
private Fragment fm_guess,fm_order,fm_setting;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
setDefaultFragment();
setOnClickLisener();
}
private void initView(){
ILay_guess = findViewById(R.id.llay_guess);
ILay_order = findViewById(R.id.llay_order);
ILay_setting = findViewById(R.id.llay_setting);
img_guess = findViewById(R.id.img_guess);
img_order = findViewById(R.id.img_order);
img_setting = findViewById(R.id.img_setting);
txt_guess = findViewById(R.id.txt_guess);
txt_order = findViewById(R.id.txt_order);
txt_setting = findViewById(R.id.txt_setting);
}
private void setDefaultFragment(){
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction transaction = fm.beginTransaction();
fm_guess = new GuessFragment();
transaction.replace(R.id.fragment_content,fm_guess,"GUESS");
transaction.commit();
}
private void setOnClickLisener(){
ILay_guess.setOnClickListener(new LinearLayoutOnClickLisener());
ILay_order.setOnClickListener(new LinearLayoutOnClickLisener());
ILay_setting.setOnClickListener(new LinearLayoutOnClickLisener());
}
private class LinearLayoutOnClickLisener implements View.OnClickListener{
@Override
public void onClick(View v) {
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction transaction = fm.beginTransaction();
resetLinearLayout();
switch (v.getId()){
case R.id.llay_guess:
if (fm_guess == null){
fm_guess = new GuessFragment();
}
img_guess.setImageResource(R.drawable.game_on);
txt_guess.setTextColor(ContextCompat.getColor(MainActivity.this,R.color.color_txt_pressed));
transaction.replace(R.id.fragment_content,fm_guess,"GUESS");
break;
case R.id.llay_order:
if (fm_order == null){
fm_order = new OrderFragment();
}
img_order.setImageResource(R.drawable.rank_on);
txt_order.setTextColor(ContextCompat.getColor(MainActivity.this,R.color.color_txt_pressed));
transaction.replace(R.id.fragment_content,fm_order,"ORDER");
break;
case R.id.llay_setting:
if (fm_setting == null){
fm_setting = new SettingFragment();
}
img_setting.setImageResource(R.drawable.setting_on);
txt_setting.setTextColor(ContextCompat.getColor(MainActivity.this,R.color.color_txt_pressed));
transaction.replace(R.id.fragment_content,fm_setting,"SETTING");
break;
}
transaction.commit();
}
}
private void resetLinearLayout(){
img_guess.setImageResource(R.drawable.game_off);
img_order.setImageResource(R.drawable.rank_off);
img_setting.setImageResource(R.drawable.setting_off);
txt_guess.setTextColor(ContextCompat.getColor(MainActivity.this,R.color.color_txt_normal));
txt_order.setTextColor(ContextCompat.getColor(MainActivity.this,R.color.color_txt_normal));
txt_setting.setTextColor(ContextCompat.getColor(MainActivity.this,R.color.color_txt_normal));
}
}
【“设置”模块的实现】
在对应的布局文件“fragment_setting.xml”中，代码布局如下：
<LinearLayout xmlns:android="schemas.android.com/apk/res/and…"
xmlns:app="schemas.android.com/apk/res-aut…"
xmlns:tools="schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".SettingFragment"
android:orientation="vertical">
<TextView
android:id="@+id/txt_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/txt_name"
android:textSize="22dp"/>
<EditText
android:id="@+id/edit_defaultName"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:padding="8dp"
android:hint="@string/edit_name"
android:textSize="22dp" />
<CheckBox
android:id="@+id/chb_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="@string/chb_useDefaultName"
android:textSize="22dp"
/>
<TextView
android:id="@+id/txt_defaultRange"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="@string/txt_defaultRange"
android:textSize="22dp"/>
<Spinner
android:id="@+id/spinner"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:entries="@array/range_array"
android:layout_marginTop="10dp"/>
<Button
android:id="@+id/btn_save"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="@string/btn_setting"
android:textSize="22dp"/>
布局文件中涉及的“strings.xml”文件内容如下：
请输入默认姓名:
使用默认姓名:
默认范围:
保存设置
默认姓名
100
1000
10000
该模块的逻辑实现代码在“SettingFragment”类中实现：
package com.example.mygame;
import android.content.Context;
import android.content.SharedPreferences;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.Toast;
public class SettingFragment extends Fragment{
private EditText edit_name;
private Button btn_save;
private CheckBox chb_defaultName;
private Spinner spinner;
private Context context;
@Override
public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState){
View view = inflater.inflate(R.layout.fragment_setting,container,false);
context = view.getContext();
initView(view);
btn_save.setOnClickListener(new ButtonOnClickLisener());
return view;
}
private void initView(View view){
edit_name = view.findViewById(R.id.edit_defaultName);
btn_save = view.findViewById(R.id.btn_save);
chb_defaultName = view.findViewById(R.id.chb_name);
spinner = view.findViewById(R.id.spinner);
}
public class ButtonOnClickLisener implements View.OnClickListener{
@Override
public void onClick(View v) {
SharedPreferences sharedPreferences = context.getSharedPreferences("Info",Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
int defaultRange = Integer.valueOf(spinner.getSelectedItem().toString());
editor.putInt("range",defaultRange);
if (chb_defaultName.isChecked()){
String defaultName = edit_name.getText().toString();
if (defaultName.isEmpty()){
Toast.makeText(context,"请输入默认姓名！",Toast.LENGTH_SHORT).show();
return;
}
editor.putString("name",defaultName);
}
else {
editor.remove("name");
}
if (editor.commit()){
Toast.makeText(context,"保存成功！",Toast.LENGTH_SHORT).show();
}
}
}
}
完成可执行run，在模拟器跑一下。
【“猜数”模块的实现】
猜数模块布局文件"fragment_guess.xml"内容如下：
<RelativeLayout xmlns:android="schemas.android.com/apk/res/and…"
xmlns:app="schemas.android.com/apk/res-aut…"
xmlns:tools="schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".GuessFragment"
android:background="#ffffff"
android:orientation="vertical">
<TextView
android:id="@+id/txt_range"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="5dp"
android:textSize="22dp"/>
<EditText
android:id="@+id/edit_num"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:layout_below="@id/txt_range"
android:padding="8dp"
android:inputType="numberSigned"
android:textSize="22dp"/>
<Button
android:id="@+id/btn_submit"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:layout_below="@id/edit_num"
android:textSize="22dp"/>
<TextView
android:id="@+id/txt_compare"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:textSize="22dp"
android:layout_below="@id/btn_submit"
android:layout_centerHorizontal="true"/>
<ImageView
android:id="@+id/img_broad"
android:layout_width="60dp"
android:layout_height="60dp"
android:layout_margin="10dp"
android:layout_toStartOf="@id/txt_compare"
android:layout_toLeftOf="@id/txt_compare"
android:layout_below="@id/btn_submit"/>
<TextView
android:id="@+id/txt_count"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:textSize="22dp"
android:layout_below="@id/txt_compare"
android:layout_alignLeft="@id/txt_compare"
android:layout_alignStart="@id/txt_compare"
/>
<ImageView
android:id="@+id/img_bingo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/img_broad"
android:layout_centerHorizontal="true"
android:layout_marginTop="10dp"
android:src="@drawable/bingo"/>
在GuessFragment类中实现猜数判断逻辑：
package com.example.mygame;
import android.content.ContentValues;
import android.content.Context;
import android.content.SharedPreferences;
import android.database.sqlite.SQLiteDatabase;
import android.support.v4.app.Fragment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import java.util.Random;
public class GuessFragment extends Fragment {
private int count,rndNum;
private EditText edit_num;
private TextView txt_range,txt_compare,txt_count;
private Button btn_submit;
private ImageView img_broad,img_bingo;
private boolean flag;
private String name;
public int range = 0;
private Context context;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState){
View view = inflater.inflate(R.layout.fragment_guess,container,false);
context = view.getContext();
initView(view);
initData();
btn_submit.setOnClickListener(new ButtonOnClickLisener());
return view;
}
private void initView(View view){
edit_num = view.findViewById(R.id.edit_num);
txt_range = view.findViewById(R.id.txt_range);
txt_compare = view.findViewById(R.id.txt_compare);
txt_count = view.findViewById(R.id.txt_count);
btn_submit = view.findViewById(R.id.btn_submit);
img_broad = view.findViewById(R.id.img_broad);
img_bingo = view.findViewById(R.id.img_bingo);
}
public void initData(){
SharedPreferences sharedPreferences = context.getSharedPreferences("Info",Context.MODE_PRIVATE);
name = sharedPreferences.getString("name","");
range = sharedPreferences.getInt("range",100);
Random mRandom = new Random();
rndNum = mRandom.nextInt(range)+1;
txt_range.setText("请输入1-"+range+"之间的整数");
txt_count.setText("");
txt_compare.setText("");
img_broad.setVisibility(View.INVISIBLE);
img_bingo.setVisibility(View.INVISIBLE);
btn_submit.setText("提交");
flag = true;
count = 0;
}
private class ButtonOnClickLisener implements View.OnClickListener{
@Override
public void onClick(View v) {
if (flag){
String str_num = edit_num.getText().toString();
if (str_num.isEmpty()){
Toast.makeText(context,"请输入数字！",Toast.LENGTH_SHORT).show();
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