郑州app开发实现篮球赛记分器。下面是java代码：
下面是MainActivity.java
package cn.xhhkj.cao;
import androidx.appcompat.app.AppCompatActivity;
import androidx.databinding.DataBindingUtil;
import androidx.lifecycle.ViewModelProviders;
import android.os.Bundle;
import cn.xhhkj.cao.databinding.ActivityMainBinding;
public class MainActivity extends AppCompatActivity {
MyViewModel myViewModel;
ActivityMainBinding binding;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
binding = DataBindingUtil.setContentView(this,R.layout.activity_main);
myViewModel= ViewModelProviders.of(this).get(MyViewModel.class);
binding.setData(myViewModel);
binding.setLifecycleOwner(this);
}
}
下面是MyViewModel.java
package cn.xhhkj.cao;
import androidx.lifecycle.MutableLiveData;
import androidx.lifecycle.ViewModel;
public class MyViewModel extends ViewModel {
private MutableLiveData
private MutableLiveData
private int aBack,bBack;
public MutableLiveData
if (aTeamScore== null){
aTeamScore=new MutableLiveData<>();
aTeamScore.setValue(0);
}
return aTeamScore;
}
public MutableLiveData
if (bTeamScore== null){
bTeamScore=new MutableLiveData<>();
bTeamScore.setValue(0);
}
return bTeamScore;
}
public void aTeamAdd(int p){
aBack=aTeamScore.getValue();
bBack=bTeamScore.getValue();
aTeamScore.setValue(aTeamScore.getValue()+p);
}
public void bTeamAdd(int p){
aBack=aTeamScore.getValue();
bBack=bTeamScore.getValue();
bTeamScore.setValue(bTeamScore.getValue()+p);
}
public void reset(){
aBack=aTeamScore.getValue();
bBack=bTeamScore.getValue();
aTeamScore.setValue(0);
bTeamScore.setValue(0);
}
public void undo(){
aTeamScore.setValue(aBack);
bTeamScore.setValue(bBack);
}
}
布局代码如下
{?xml version="1.0" encoding="utf-8"?}
{layout 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"}
{data}
{variable
name="data"
type="cn.xhhkj.cao.MyViewModel" /}
{/data}
{androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"}
{androidx.constraintlayout.widget.Guideline
android:id="@+id/guideline"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_begin="44dp" /}
{androidx.constraintlayout.widget.Guideline
android:id="@+id/guideline2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_begin="157dp" /}
{androidx.constraintlayout.widget.Guideline
android:id="@+id/guideline3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_begin="269dp" /}
{androidx.constraintlayout.widget.Guideline
android:id="@+id/guideline4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_begin="386dp" /}
{androidx.constraintlayout.widget.Guideline
android:id="@+id/guideline5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_begin="502dp" /}
{androidx.constraintlayout.widget.Guideline
android:id="@+id/guideline6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_begin="604dp" /}
{androidx.constraintlayout.widget.Guideline
android:id="@+id/guideline7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_end="39dp" /}
{androidx.constraintlayout.widget.Guideline
android:id="@+id/guideline8"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_begin="205dp" /}
{TextView
android:id="@+id/TeamA"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/teama"
android:textSize="14sp"
app:layout_constraintBottom_toTopOf="@+id/guideline2"
app:layout_constraintEnd_toStartOf="@+id/guideline8"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/guideline" /}
{TextView
android:id="@+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/teamb"
android:textSize="14sp"
app:layout_constraintBottom_toTopOf="@+id/guideline2"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="@+id/guideline8"
app:layout_constraintTop_toTopOf="@+id/guideline" /}
{TextView
android:id="@+id/textView5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@{String.valueOf(data.getaTeamScore())}"
android:textSize="24sp"
app:layout_constraintBottom_toTopOf="@+id/guideline3"
app:layout_constraintEnd_toStartOf="@+id/guideline8"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/guideline2" /}
{TextView
android:id="@+id/textView7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@{String.valueOf(data.getbTeamScore)}"
android:textSize="24sp"
app:layout_constraintBottom_toTopOf="@+id/guideline3"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="@+id/guideline8"
app:layout_constraintTop_toTopOf="@+id/guideline2" /}
{Button
android:id="@+id/button2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="@color/colorAccent"
android:text="@string/_1"
android:onClick="@{()-}data.aTeamAdd(1)}"
android:textColor="@android:color/background_light"
app:layout_constraintBottom_toTopOf="@+id/guideline4"
app:layout_constraintEnd_toStartOf="@+id/guideline8"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/guideline3" /}
{Button
android:id="@+id/button3"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="@color/colorPrimary"
android:text="@string/b_1"
android:onClick="@{()-}data.bTeamAdd(1)}"
android:textColor="@android:color/background_light"
app:layout_constraintBottom_toTopOf="@+id/guideline4"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="@+id/guideline8"
app:layout_constraintTop_toTopOf="@+id/guideline3" /}
{Button
android:id="@+id/button4"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="@color/colorAccent"
android:text="@string/a_2"
android:onClick="@{()-}data.aTeamAdd(2)}"
android:textColor="@android:color/background_light"
app:layout_constraintBottom_toTopOf="@+id/guideline5"
app:layout_constraintEnd_toStartOf="@+id/guideline8"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/guideline4" /}
{Button
android:id="@+id/button5"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="@color/colorPrimary"
android:text="@string/_2"
android:onClick="@{()-}data.bTeamAdd(2)}"
android:textColor="@android:color/background_light"
app:layout_constraintBottom_toTopOf="@+id/guideline5"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="@+id/guideline8"
app:layout_constraintTop_toTopOf="@+id/guideline4" /}
{Button
android:id="@+id/button6"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="@color/colorAccent"
android:onClick="@{()-}data.aTeamAdd(3)}"
android:text="@string/a_3"
android:textColor="@android:color/background_light"
app:layout_constraintBottom_toTopOf="@+id/guideline6"
app:layout_constraintEnd_toStartOf="@+id/guideline8"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/guideline5" /}
{Button
android:id="@+id/button7"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="@color/colorPrimary"
android:onClick="@{()-}data.bTeamAdd(3)}"
android:text="@string/_3"
android:textColor="@android:color/background_light"
app:layout_constraintBottom_toTopOf="@+id/guideline6"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="@+id/guideline8"
app:layout_constraintTop_toTopOf="@+id/guideline5" /}
{ImageButton
android:id="@+id/imageButton2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="@string/undo"
android:onClick="@{()-}data.undo()}"
app:layout_constraintBottom_toTopOf="@+id/guideline7"
app:layout_constraintEnd_toStartOf="@+id/guideline8"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/guideline6"
app:srcCompat="@android:drawable/ic_media_rew" /}
{ImageButton
android:id="@+id/imageButton3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="@string/resert"
app:layout_constraintBottom_toTopOf="@+id/guideline7"
app:layout_constraintEnd_toEndOf="parent"
android:onClick="@{()-}data.reset()}"
app:layout_constraintHorizontal_bias="0.466"
app:layout_constraintStart_toStartOf="@+id/guideline8"
app:layout_constraintTop_toTopOf="@+id/guideline6"
app:srcCompat="@android:drawable/ic_media_ff" /}
{/androidx.constraintlayout.widget.ConstraintLayout}
{/layout}
总结下，这个计分器虽然简单，但里面已经把数据的处理放到单独的文件里面，而不是入口文件，入口文件非常简略，这样方便后期的维护。
