android开发之绘制圆形头像

现在很多android项目都涉及到了圆形头像,特别是在登录界面中随处可见!可是,我不会,怎么办?不用怕,快用小二颗粒!妈妈再也不用担心我的学习了!不是啦,接下来我就给大家分享分享在android中怎么绘制圆形头像.

首先直接上个图,有图有真相嘛:

第一步:首先在/res/values/attrs.xml下:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="CircleImageView">
        <attr name="border_width" format="dimension"/>
        <attr name="border_color" format="color"/>
    </declare-styleable>
</resources>

第二步:当然是我们最爱的自定义的View啦

首先:创建一个类(CircleImageView)继承ImageView.

然后:覆写构造方法.

public class CircleImageView extends ImageView {

    private static final ScaleType SCALE_TYPE = ScaleType.CENTER_CROP;

    private static final Bitmap.Config BITMAP_CONFIG = Bitmap.Config.ARGB_8888;
    private static final int COLORDRAWABLE_DIMENSION = 2;

    private static final int DEFAULT_BORDER_WIDTH = 0;
    private static final int DEFAULT_BORDER_COLOR = Color.BLACK;

    private final RectF mDrawableRect = new RectF();
    private final RectF mBorderRect = new RectF();

    private final Matrix mShaderMatrix = new Matrix();
    private final Paint mBitmapPaint = new Paint();
    private final Paint mBorderPaint = new Paint();

    private int mBorderColor = DEFAULT_BORDER_COLOR;
    private int mBorderWidth = DEFAULT_BORDER_WIDTH;

    private Bitmap mBitmap;
    private BitmapShader mBitmapShader;
    private int mBitmapWidth;
    private int mBitmapHeight;

    private float mDrawableRadius;
    private float mBorderRadius;

    private ColorFilter mColorFilter;

    private boolean mReady;
    private boolean mSetupPending;


    public CircleImageView(Context context) {
        this(context, null);
    }

    public CircleImageView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public CircleImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);

        //获取自定义属性
        TypedArray ta = context.obtainStyledAttributes(attrs,R.styleable.CircleImageView,defStyle,0);
        mBorderWidth = ta.getDimensionPixelSize(R.styleable.CircleImageView_border_width,DEFAULT_BORDER_WIDTH);
        mBorderColor = ta.getColor(R.styleable.CircleImageView_border_color,DEFAULT_BORDER_COLOR);
        //释放资源,防止缓存数据
        ta.recycle();

        init();
    }

    private void init() {
        super.setScaleType(SCALE_TYPE);
        mReady = true;
        if(mSetupPending){
            setup();
            mSetupPending = false;
        }
    }

    @Override
    public ScaleType getScaleType() {
        return SCALE_TYPE;
    }

    @Override
    public void setScaleType(ScaleType scaleType) {
        if(SCALE_TYPE != SCALE_TYPE){
            throw new IllegalArgumentException(String.format("ScaleType %s not supported.",scaleType));
        }
    }

    @Override
    public void setAdjustViewBounds(boolean adjustViewBounds) {
        if(adjustViewBounds) {
            throw new IllegalArgumentException("adjustViewBounds not supported.");
        }
    }

    @Override
    protected void onDraw(Canvas canvas) {
        if(getDrawable() == null) {
            return;
        }
        canvas.drawCircle(getWidth()/2,getHeight()/2,mDrawableRadius,mBitmapPaint);
        if(mBorderWidth != 0) {
            canvas.drawCircle(getWidth()/2,getHeight()/2,mBorderRadius,mBorderPaint);
        }
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        setup();
    }

    public int getBorderColor() {
        return mBorderColor;
    }

    public void setBorderColor(int borderColor) {
        if(borderColor == mBorderColor) {
            return;
        }

        mBorderColor = borderColor;
        mBorderPaint.setColor(mBorderColor);
        invalidate();
    }

    public int getBorderWidth(){
        return mBorderWidth;
    }

    public void setBorderWidth(int borderWidth) {
        if (borderWidth == mBorderWidth) {
            return;
        }

        mBorderWidth = borderWidth;
        setup();
    }

    @Override
    public void setImageBitmap(Bitmap bm) {
        super.setImageBitmap(bm);
        mBitmap = bm;
        setup();
    }

    @Override
    public void setImageDrawable(Drawable drawable) {
        super.setImageDrawable(drawable);
        mBitmap = getBitmapFromDrawable(drawable);
        setup();
    }

    @Override
    public void setImageResource(int resId) {
        super.setImageResource(resId);
        mBitmap = getBitmapFromDrawable(getDrawable());
        setup();
    }

    @Override
    public void setImageURI(Uri uri) {
        super.setImageURI(uri);
        mBitmap = getBitmapFromDrawable(getDrawable());
        setup();
    }

    @Override
    public void setColorFilter(ColorFilter cf) {
        if (cf == mColorFilter) {
            return;
        }

        mColorFilter = cf;
        mBitmapPaint.setColorFilter(mColorFilter);
        invalidate();
    }

    private Bitmap getBitmapFromDrawable(Drawable drawable) {
        if (drawable == null) {
            return null;
        }

        if (drawable instanceof BitmapDrawable) {
            return ((BitmapDrawable) drawable).getBitmap();
        }

        try {
            Bitmap bitmap;

            if (drawable instanceof ColorDrawable) {
                bitmap = Bitmap.createBitmap(COLORDRAWABLE_DIMENSION, COLORDRAWABLE_DIMENSION, BITMAP_CONFIG);
            } else {
                bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), BITMAP_CONFIG);
            }

            Canvas canvas = new Canvas(bitmap);
            drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
            drawable.draw(canvas);
            return bitmap;
        } catch (OutOfMemoryError e) {
            return null;
        }
    }

    private void setup() {
        if (!mReady) {
            mSetupPending = true;
            return;
        }

        if (mBitmap == null) {
            return;
        }

        mBitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);

        mBitmapPaint.setAntiAlias(true);
        mBitmapPaint.setShader(mBitmapShader);

        mBorderPaint.setStyle(Paint.Style.STROKE);
        mBorderPaint.setAntiAlias(true);
        mBorderPaint.setColor(mBorderColor);
        mBorderPaint.setStrokeWidth(mBorderWidth);

        mBitmapHeight = mBitmap.getHeight();
        mBitmapWidth = mBitmap.getWidth();

        mBorderRect.set(0, 0, getWidth(), getHeight());
        mBorderRadius = Math.min((mBorderRect.height() - mBorderWidth) / 2, (mBorderRect.width() - mBorderWidth) / 2);

        mDrawableRect.set(mBorderWidth, mBorderWidth, mBorderRect.width() - mBorderWidth, mBorderRect.height() - mBorderWidth);
        mDrawableRadius = Math.min(mDrawableRect.height() / 2, mDrawableRect.width() / 2);

        updateShaderMatrix();
        invalidate();
    }

    private void updateShaderMatrix() {
        float scale;
        float dx = 0;
        float dy = 0;

        mShaderMatrix.set(null);

        if (mBitmapWidth * mDrawableRect.height() > mDrawableRect.width() * mBitmapHeight) {
            scale = mDrawableRect.height() / (float) mBitmapHeight;
            dx = (mDrawableRect.width() - mBitmapWidth * scale) * 0.5f;
        } else {
            scale = mDrawableRect.width() / (float) mBitmapWidth;
            dy = (mDrawableRect.height() - mBitmapHeight * scale) * 0.5f;
        }

        mShaderMatrix.setScale(scale, scale);
        mShaderMatrix.postTranslate((int) (dx + 0.5f) + mBorderWidth, (int) (dy + 0.5f) + mBorderWidth);

        mBitmapShader.setLocalMatrix(mShaderMatrix);
    }
}

第三步:引用自定义View和自定义属性:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              xmlns:tools="http://schemas.android.com/tools"
              xmlns:app="http://schemas.android.com/apk/res-auto"//引用自定义属性
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:orientation="vertical"
              tools:context="com.example.circleimageviewdemo.MainActivity$PlaceholderFragment">

    <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:padding="@dimen/base_padding"
            android:background="@color/light">
        //引用自定义View
        <com.example.circleimageviewdemo.CircleImageView
                android:layout_width="160dp"
                android:layout_height="160dp"
                android:layout_centerInParent="true"
                android:src="@drawable/zane"
                app:border_width="2dp"
                app:border_color="@color/dark" />

    </RelativeLayout>

    <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:padding="@dimen/base_padding"
            android:background="@color/dark">

        <com.example.circleimageviewdemo.CircleImageView
                android:layout_width="160dp"
                android:layout_height="160dp"
                android:layout_centerInParent="true"
                android:src="@drawable/zane"
                app:border_width="2dp"
                app:border_color="@color/light" />
    </RelativeLayout>
</LinearLayout>

第四步:让我的头像圆起来

public class MyActivity extends Activity {
    /**
     * Called when the activity is first created.
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        if(savedInstanceState == null) {
            getFragmentManager().beginTransaction().add(R.id.container,new MainFragment()).commit();//替换
        }
    }

    public static class MainFragment extends Fragment {
        public MainFragment(){}

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main,container,false);
            return rootView;
        }
    }
}

附件:

1.activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
             xmlns:tools="http://schemas.android.com/tools"
             android:id="@+id/container"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             tools:context="com.example.circleimageviewdemo.MyActivity"
             tools:ignore="MergeRootFrame" />

2.colors.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="dark">#FF222222</color>
    <color name="light">#FFEEEEEE</color>
</resources>

3.dimens.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <dimen name="base_padding">16dp</dimen>
</resources>

-----------------------------------------------------------------上面的太难了,下面的来个简单点的----------------------------------------------------------

第一步:来个自定义View,该类是一个抽象类,所有的类都继承于此!

public abstract class MaskedImage extends ImageView {
    private static final Xfermode MASK_XFERMODE;
    private Bitmap mask;
    private Paint paint;

    static {
        PorterDuff.Mode localMode = PorterDuff.Mode.DST_IN;
        MASK_XFERMODE = new PorterDuffXfermode(localMode);
    }

    public MaskedImage(Context context) {
        this(context, null);
    }

    public MaskedImage(Context context, AttributeSet attrs) {
        this(context, attrs ,0);
    }

    public MaskedImage(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);

    }

    public abstract Bitmap createMask();

    protected void onDraw(Canvas paramCanvas) {
        Drawable localDrawable = getDrawable();
        if (localDrawable == null)
            return;
        try {
            if (this.paint == null) {
                Paint localPaint1 = new Paint();
                this.paint = localPaint1;
                this.paint.setFilterBitmap(false);
                Paint localPaint2 = this.paint;
                Xfermode localXfermode1 = MASK_XFERMODE;
                @SuppressWarnings("unused")
                Xfermode localXfermode2 = localPaint2.setXfermode(localXfermode1);
            }
            float f1 = getWidth();
            float f2 = getHeight();
            int i = paramCanvas.saveLayer(0.0F, 0.0F, f1, f2, null, 31);
            int j = getWidth();
            int k = getHeight();
            localDrawable.setBounds(0, 0, j, k);
            localDrawable.draw(paramCanvas);
            if ((this.mask == null) || (this.mask.isRecycled())) {
                Bitmap localBitmap1 = createMask();
                this.mask = localBitmap1;
            }
            Bitmap localBitmap2 = this.mask;
            Paint localPaint3 = this.paint;
            paramCanvas.drawBitmap(localBitmap2, 0.0F, 0.0F, localPaint3);
            paramCanvas.restoreToCount(i);
            return;
        } catch (Exception localException) {
            StringBuilder localStringBuilder = new StringBuilder().append("Attempting to draw with recycled bitmap. View ID = ");
            System.out.println("localStringBuilder=="+localStringBuilder);
        }
    }
}

第二步:创建一个类继承MaskedImage:

public class CircleImageView extends MaskedImage{
    public CircleImageView(Context context) {
        this(context, null);
    }

    public CircleImageView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public CircleImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    public Bitmap createMask() {
        int i = getWidth();
        int j = getHeight();
        Bitmap.Config localConfig = Bitmap.Config.ARGB_8888;
        Bitmap localBitmap = Bitmap.createBitmap(i, j, localConfig);
        Canvas localCanvas = new Canvas(localBitmap);
        Paint localPaint = new Paint(1);
        localPaint.setColor(-16777216);
        float f1 = getWidth();
        float f2 = getHeight();
        RectF localRectF = new RectF(0.0F, 0.0F, f1, f2);
        localCanvas.drawOval(localRectF, localPaint);
        return localBitmap;
    }
}

第三步:来个布局文件,引用自定义View

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:gravity="center" >

    <!--<ImageView
            android:layout_width="82.0dip"
            android:layout_height="82.0dip"
            android:layout_centerInParent="true"
            android:contentDescription="@null"
            android:src="@drawable/zane" />-->
    //引用自定义View
    <com.example.circleimageviewdemo2.CircleImageView
            android:id="@+id/cover_user_photo"
            android:layout_width="74.0dip"
            android:layout_height="74.0dip"
            android:layout_centerInParent="true" />

</RelativeLayout>

第四步:让我们的头像圆起来

public class MyActivity extends Activity {
    /**
     * Called when the activity is first created.
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        //让我们的头像圆起来
        CircleImageView circleImageView = (CircleImageView) findViewById(R.id.cover_user_photo);
        circleImageView.setImageResource(R.drawable.zane);
    }
}

免责声明:转载http://blog.csdn.net/dajian790626/article/details/17043347