本文实例为大家分享了Android实现购物车加减商品操作的具体代码，供大家参考，具体内容如下

MainActivity.java

public class MainActivity extends AppCompatActivity {

private Addand mAddand;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

mAddand= findViewById(R.id.add);

mAddand.setOnNumberChangedListener(new Addand.OnNumberChangedListener() {

@Override

public void OnNumberChanged(int vs) {

Toast.makeText(MainActivity.this, vs+"", Toast.LENGTH_SHORT).show();

}

});

}

}

activity_main.xml

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="horizontal">

android:id="@+id/add"

android:layout_width="wrap_content"

android:layout_height="wrap_content"/>

Addand.java

public class Addand extends FrameLayout implements View.OnClickListener{

private ImageView mImage1;

private ImageView mImage2;

private TextView mText;

int value;

public Addand(@NonNull Context context) {

this(context,null);

}

public Addand(@NonNull Context context, @Nullable AttributeSet attrs) {

this(context, attrs,0);

}

public Addand(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {

super(context, attrs, defStyleAttr);

findView(context);

}

private void findView(Context context) {

View view = View.inflate(context, R.layout.add, this);

mImage1 =view.findViewById(R.id.image1);

mImage2 = view.findViewById(R.id.image2);

mText = view.findViewById(R.id.text);

value=getValue();

setValue(value);

mImage1.setOnClickListener(this);

mImage2.setOnClickListener(this);

}

private int vs=1;

public int getValue() { //获取值

String trim = mText.getText().toString().trim();

if (!TextUtils.isEmpty(trim)){

Integer.valueOf(vs);

}

return vs;

}

public void setValue(int value) {

mText.setText(value+"");

}

@Override

public void onClick(View view) {

switch (view.getId()){

case R.id.image1:

add();

break;

case R.id.image2:

jian();

break;

}

}

private void jian() {

if (vs>1){

vs--;

setValue(vs);

}

mOnNumberChangedListener.OnNumberChanged(vs);

}

private void add() {

if (vs<6){

vs++;

setValue(vs);

}

mOnNumberChangedListener.OnNumberChanged(vs);

}

public interface OnNumberChangedListener{

void OnNumberChanged(int vs);

}

private OnNumberChangedListener mOnNumberChangedListener;

public void setOnNumberChangedListener(OnNumberChangedListener onNumberChangedListener){

mOnNumberChangedListener=onNumberChangedListener;

}

}

add.xml

android:layout_width="match_parent"

android:layout_height="match_parent"

android:orientation="horizontal">

android:id="@+id/image1"

android:layout_width="20dp"

android:layout_height="20dp"

android:src="@drawable/ic_launcher_background"/>

android:id="@+id/text"

android:layout_width="50dp"

android:layout_height="20dp"

android:gravity="center"

android:text="1"/>

android:id="@+id/image2"

android:layout_width="20dp"

android:layout_height="20dp"

android:src="@drawable/ic_launcher_background"/>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持找一找教程网。