Android自定义view：自定义属性 TypedArray

Posted 2022-03-16 Mars-xq

定义：

<declare-styleable name="MyView">
    <attr name="vColor" format="color" />
    <attr name="vDrawable" format="color|reference" />
    <attr name="vDimen" format="dimension" />
    <attr name="vReference" format="reference" />
    <attr name="vBoolean" format="boolean" />
    <attr name="vFloat" format="float" />
    <attr name="vInteger" format="integer" />
    <attr name="vString" format="string" />
    <attr name="vFraction" format="fraction" />

    <attr name="vType" format="enum">
        <enum name="type1" value="1" />
        <enum name="type2" value="2" />
        <enum name="type3" value="3" />
    </attr>

    <attr name="vFlag" format="flags">
        <flag name="flag1" value="0x1" />
        <flag name="flag2" value="0x2" />
        <flag name="flag3" value="0x3" />
    </attr>
</declare-styleable>

attrs中的format属性	TypedArray对应方法	返回	备注
reference	getInt	int
color	getColor	int
boolean	getBoolean	boolean
dimension	getDimension	float
float	getFloat	float
integer	getInteger，getInt	Integer，int
string	getString	String	必须是资源文件中的字符串
fraction	getFraction	float
enum	getInt，getInteger，getFloat，getString	int，Integer，float，String	返回的全是value的值
flag	getInt，getFloat，getString	int，float，string	返回value值的或运算值

声明

public class MyView extends View 
    private static final String TAG = MyView.class.getSimpleName();

    public MyView(Context context) 
        this(context, null);
    

    public MyView(Context context, @Nullable AttributeSet attrs) 
        this(context, attrs, -1);
    

    public MyView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) 
        super(context, attrs, defStyleAttr);

        TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.MyView);
        
        int vColor = typedArray.getColor(R.styleable.MyView_vColor, getResources().getColor(R.color.black));
        // ColorDrawable / BitmapDrawable
        Drawable vDrawable = typedArray.getDrawable(R.styleable.MyView_vDrawable);
        float vDimen = typedArray.getDimension(R.styleable.MyView_vDimen, dp2px(20));
        float vFloat = typedArray.getFloat(R.styleable.MyView_vFloat, -1F);
        int vInteger = typedArray.getInteger(R.styleable.MyView_vInteger, -1);
        boolean vBoolean = typedArray.getBoolean(R.styleable.MyView_vBoolean, false);
        String vString = typedArray.getString(R.styleable.MyView_vString);
        int vReference = typedArray.getResourceId(R.styleable.MyView_vReference, R.mipmap.ic_launcher);
        int vType = typedArray.getInteger(R.styleable.MyView_vType, -1);
        int vFlag = typedArray.getInt(R.styleable.MyView_vFlag, 0);
        Log.e(TAG, "MyView:vColor===============> " + vColor);
        Log.e(TAG, "MyView:vDrawable===============> " + vDrawable);
        Log.e(TAG, "MyView:vDimen===============> " + vDimen);
        Log.e(TAG, "MyView:vFloat===============> " + vFloat);
        Log.e(TAG, "MyView:vInteger===============> " + vInteger);
        Log.e(TAG, "MyView:vBoolean===============> " + vBoolean);
        Log.e(TAG, "MyView:vString===============> " + vString);
        Log.e(TAG, "MyView:vReference===============> " + vReference);
        Log.e(TAG, "MyView:vType===============> " + vType);
        Log.e(TAG, "MyView:vFlag===============> " + vFlag);

        typedArray.recycle();
    

    /**
     * dp转px
     *
     * @param dp dp值
     * @return px值
     */
    public int dp2px(float dp) 
        return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp,
                getResources().getDisplayMetrics());
    

    /**
     * sp转px
     *
     * @param sp sp值
     * @return px值
     */
    private int sp2px(float sp) 
        return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, sp,
                getResources().getDisplayMetrics());
    

使用

<com.xq.myapplication.view.MyView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    app:vBoolean="true"
    app:vColor="#000000"
    app:vDimen="18dp"
    app:vDrawable="@android:color/white"
    app:vFlag="flag1|flag2|flag3"
    app:vFloat="3.14"
    app:vInteger="10086"
    app:vReference="@mipmap/ic_launcher"
    app:vString="自定义属性"
    app:vType="type3" />

drawable 的绘制

void drawDrawable(Canvas canvas, Rect bound,Drawable drawable) 
    drawable.setBounds(bounds);
    drawable.draw(canvas);