一个简单的猜数字APP（一）

使用约束布局ConstraintLayout，郭霖大神的ConstraintLayout解析

进入界面

如上图，关键是一个进入按钮，进入猜数字界面，无它

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:orientation="vertical">

    <TextView
        android:id="@+id/m_tv_title"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:padding="45dp"
        android:text="猜数游戏"
        android:textColor="#000000"
        android:textSize="25sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.26999998" />


    <Button
        android:id="@+id/btn_start"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="开始游戏"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/m_tv_title"
        app:layout_constraintVertical_bias="0.45" />


</androidx.constraintlayout.widget.ConstraintLayout>

package com.aaa_xcdq.gnumber;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    private Button button;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button=findViewById(R.id.btn_start);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(MainActivity.this,PalyActivity.class));
            }
        });
    }
}

游戏界面

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".PalyActivity"
    android:orientation="vertical"
    android:gravity="center">

    <EditText
        android:id="@+id/editText"
        android:layout_width="100dp"
        android:layout_height="50dp"
        android:background="@drawable/et_number"
        android:gravity="center"
        android:inputType="number"
        app:layout_constraintBottom_toTopOf="@+id/button"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.52"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.507" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        app:layout_constraintBottom_toTopOf="@+id/button"
        app:layout_constraintTop_toBottomOf="@+id/editText">


        <TextView
            android:id="@+id/tv_number"
            android:layout_width="46dp"
            android:layout_height="46dp"
            android:text="number"
            android:textSize="30sp"
            android:textColor="#000000"
            android:gravity="center"
            tools:layout_editor_absoluteX="59dp"
            tools:layout_editor_absoluteY="267dp" />

        <TextView
            android:id="@+id/tv_things"
            android:layout_width="200dp"
            android:layout_height="46dp"
            android:textColor="#000"
            android:text="Things"
            android:gravity="center"
            tools:layout_editor_absoluteX="177dp"
            tools:layout_editor_absoluteY="278dp" />

        <ImageView
            android:id="@+id/imageView"
            android:layout_width="40dp"
            android:layout_height="40dp"
            tools:layout_editor_absoluteX="302dp"
            tools:layout_editor_absoluteY="254dp" />
    </LinearLayout>

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="确定"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.501"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.477" />


</androidx.constraintlayout.widget.ConstraintLayout>

输入框背景

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<corners android:radius="5dp"/>
    <stroke android:color="@color/colorPrimary" android:width="2dp"/>
</shape>

游戏活动

package com.aaa_xcdq.gnumber;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.util.TimeUtils;
import android.view.View;
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 PalyActivity extends AppCompatActivity {

    private TextView tvNumber, tvThings;
    private Button btnYes;
    private EditText etNumber;
    private int number_in, number_time = 10, number_right;
    private ImageView imageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_paly);
        initView();
        
        //正确数字随机生成
        number_right = new Random().nextInt(10);
        tvThings.setText("请输入一个0~9的数");
        tvNumber.setText(number_time + "");
    }

    private void initView() {
        tvNumber = findViewById(R.id.tv_number);
        tvThings = findViewById(R.id.tv_things);
        etNumber = findViewById(R.id.editText);
        btnYes = findViewById(R.id.button);
        imageView = findViewById(R.id.imageView);
        
        btnYes.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //如果EditText不为空
                if (!TextUtils.isEmpty(etNumber.getText().toString())) {
                    number_in = Integer.parseInt(etNumber.getText().toString());
                    //如果输入的数字在0~10之间
                    if (number_in >= 0 && number_in < 10) {
                        if (number_in == number_right) {
                            //如果正确
                            imageView.setBackgroundResource(R.drawable.ic_yes);
                            tvThings.setText("You are right");
                        } else {
                            //如果不正确
                            imageView.setBackgroundResource(R.drawable.ic_no);
                            if (number_in > number_right) {
                                tvThings.setText("大了");
                            } else {
                                tvThings.setText("小了");
                            }

                        }
                    } else {
                        //如果输入的数字不在0~10之间

                        Toast.makeText(PalyActivity.this, "数字不符合要求", Toast.LENGTH_SHORT).show();
                    }
                }

                //游戏次数减少

                number_time--;
                tvNumber.setText(number_time + "");


            }
        });
    }
}

下一步

1. 增加提示框反馈内容
2. 游戏次数到0时停止
3. 新页面当游戏成功或失败时
4. 输入框在确认后内容自动消失，并获得焦点
5. 统计游戏次数
6. 首页可以设置游戏难度