Android 开发之 DishesView自定义点菜控件

开发中常常遇到下图需求,购物经常用到数量加减，这里封装的一个自定义控件实现该功能，以前我使用每个控件都在xml里面布局，activity或者adapter里面调用，回调实现，感觉代码有点冗杂，今日又遇到此需求，所以逗比的DishesView就此诞生了。

DishesView代码相对简单，通过自定义属性获取背景，动态的给LinearLayout添加自布局，绑定view的监听，动态更新EditText的值，同时回调给Activity.先来看看实体类：

public class Dishes {    private int id;    private float price;    private int count;    @SuppressWarnings("unused")    private float totalPrice;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public float getPrice() {        return price;    }    public void setPrice(float price) {        this.price = price;    }    public int getCount() {        return count <= 0 ? 0 : count;    }    public void setCount(int count) {        this.count = count <= 0 ? 0 : count;    }    public float getTotalPrice() {        return price * count;    }    public void setTotalPrice(float totalPrice) {        this.totalPrice = totalPrice <= 0 ? 0 : totalPrice;    }    public Dishes(int id, float price, int count, float totalPrice) {        super();        this.id = id;        this.price = price;        this.count = count;        this.totalPrice = totalPrice;    }    public Dishes(float price, int count, float totalPrice) {        super();        this.price = price;        this.count = count;        this.totalPrice = totalPrice;    }    public Dishes(float price, int count) {        super();        this.price = price;        this.count = count;    }}

这里主要是对count值进行检测，总价格动态获取。DishesView的构造函数如下：

    public DishesView(Context context) {        this(context,null);    }    public DishesView(Context context, AttributeSet attrs) {        this(context, attrs,0);    }    private DishesView(Context context, AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);        final TypedArray a= context.obtainStyledAttributes(attrs,R.styleable.dishesStyleable);        updateBackgroundFromTypedArray(a);        a.recycle();    }

调用私有构造方法后获取自定义属性值Drawable:

private void updateBackgroundFromTypedArray(TypedArray a) {        addDrawable=a.getDrawable(R.styleable.dishesStyleable_AddBackground);        deleteDrawable=a.getDrawable(R.styleable.dishesStyleable_DeleteBackground);        editTextDrawable=a.getDrawable(R.styleable.dishesStyleable_EditTextBackground);    }

下面是onMeasure测量和SizeChange监听，同时绑定控件监听

@Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        final int widthMode = MeasureSpec.getMode(widthMeasureSpec);          final int heightMode = MeasureSpec.getMode(heightMeasureSpec);          int widthSize = MeasureSpec.getSize(widthMeasureSpec);          int heightSize = MeasureSpec.getSize(heightMeasureSpec);          Resources r = Resources.getSystem();          if(widthMode == MeasureSpec.UNSPECIFIED || widthMode == MeasureSpec.AT_MOST){              widthSize = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 50, r.getDisplayMetrics());              widthMeasureSpec = MeasureSpec.makeMeasureSpec(widthSize, MeasureSpec.EXACTLY);          }          if(heightMode == MeasureSpec.UNSPECIFIED || heightSize == MeasureSpec.AT_MOST){              heightSize = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 30, r.getDisplayMetrics());              heightMeasureSpec = MeasureSpec.makeMeasureSpec(heightSize, MeasureSpec.EXACTLY);          }          super.onMeasure(widthMeasureSpec, heightMeasureSpec);      }    @Override    protected void onSizeChanged(int w, int h, int oldw, int oldh) {        // TODO Auto-generated method stub        super.onSizeChanged(w, h, oldw, oldh);        if(getChildCount()>0){            removeAllViews();        }        initialization();        mAddImageView.setOnClickListener(this);        mDeleteImageView.setOnClickListener(this);        mCountEditText.addTextChangedListener(this);        mCountEditText.setOnTouchListener(this);        mCountEditText.clearFocus();        mCountEditText.setCursorVisible(false);    }    private void initialization() {        // TODO Auto-generated method stub        setFocusable(false);        setFocusableInTouchMode(true);        setOrientation(LinearLayout.HORIZONTAL);        addView(getAddView());        addView(getEditTextView());        addView(getDeleteView());    }

通过setCursorVisible控制光标的显示，afterTextChanged该方法回调里面调用onCheck方法检测输入值的合法性和绑定Dishes的count,并执行onDishesListener回调，对外公开方法setAdapter如下：

public void setAdapter(Dishes mDishes,OnDishesListener onDishListener){        this.mDishes=mDishes;        this.onDishesListener=onDishListener;        if(onDishListener!=null){            onDishListener.onTextChanged(mDishes);        }    }

自定义属性：

<?xml version="1.0" encoding="utf-8"?><resources>    <!-- These are the standard attributes that make up a complete theme. -->    <declare-styleable name="dishStyleable">        <!-- ============= -->        <!-- DishView styles -->        <!-- ============= -->        <eat-comment />        <!-- Delete ImageView's background. -->        <attr name="DeleteBackground" format="reference" />        <!-- Add ImageView's background. -->        <attr name="AddBackground" format="reference" />        <!-- Editext's background. -->        <attr name="EditTextBackground" format="reference" />    </declare-styleable></resources>

测试xml:

<RelativeLayout 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"    android:background="#ffffff"    tools:context="com.lanyan.dish.MainActivity" >    <TextView        android:id="@+id/totalPrice"        android:layout_width="match_parent"        android:layout_height="50dp"        android:layout_alignParentTop="true"        android:gravity="center"        android:padding="10dp"        android:text="" />    <com.lanyan.widget.DishesView        android:id="@+id/dishView1"        android:layout_width="180dp"        android:layout_height="40dp"        android:layout_below="@+id/totalPrice"        android:layout_centerHorizontal="true"        android:layout_margin="10dp"        app:AddBackground="@drawable/add"        app:DeleteBackground="@drawable/delete"        app:EditTextBackground="@drawable/edittext" />    <Button        android:id="@+id/sure"        android:layout_width="match_parent"        android:layout_height="45dp"        android:layout_centerHorizontal="true"        android:layout_centerInParent="true"        android:layout_margin="20dp"        android:background="@drawable/edittext"        android:text="确定" /></RelativeLayout>

测试代码：

public class MainActivity extends Activity {    private TextView tv;    private DishesView dishesView;    private Button sure;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        tv=(TextView)findViewById(R.id.totalPrice);        dishesView=(DishesView)findViewById(R.id.dishView1);        sure=(Button)findViewById(R.id.sure);        sure.setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                // TODO Auto-generated method stub                    dishView.setCursorVisible(false);            }        });        dishesView.setAdapter(new Dishes(20, 1),new OnDishesListener() {            @Override            public void onTextChanged(Dishes bean) {                // TODO Auto-generated method stub                tv.setText("当前总价格为："+bean.getTotalPrice()+" 元 ");            }        });    }}

demo下载：http://download.csdn.net/detail/analyzesystem/8991845