Android自定義控件實例，圓形頭像（圖庫 + 裁剪+設置），上傳頭像顯示為圓形

Android項目開發中經常會遇見需要實現圓角或者圓形的圖片功能，如果僅僅使用系統自帶的ImageView控件顯然無法實現此功能，所以通過系列文章的形式由簡到繁全方位的介紹一下此功能的實現，鞏固一下自身的學習，同時，和廣大網友交流分享

首先看效果圖

首先看一下CircleImageView的主要流程

1. 首先通過setImageXxx()方法設置圖片Bitmap；

2. 進入構造函數CircleImageView()獲取自定義參數，以及調用setup()函數； 

3. 進入setup()函數（非常關鍵），進行圖片畫筆邊界畫筆(Paint)一些重繪參數初始化：構建渲染器BitmapShader用Bitmap來填充繪制區域,設置樣式和內外圓半徑計算等，以及調用updateShaderMatrix()函數和 invalidate()函數； 

4. 進入updateShaderMatrix()函數，計算縮放比例和平移，設置BitmapShader的Matrix參數等； 

5. 觸發ondraw()函數完成最終的繪制。使用配置好的Paint先畫出繪制內圓形來以后再畫邊界圓形。

下面看具體的代碼實現：

attr.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="roundedimageview">
        <attr name="border_thickness" format="dimension" />
        <attr name="border_inside_color" format="color" />
        <attr name="border_outside_color" format="color"></attr>
    </declare-styleable>
</resources>

然后是自定義ImageView的實現類：

RoundImageView.class
        

**
 * 圓形ImageView，可設置最多兩個寬度不同且顏色不同的圓形邊框。
 * 設置顏色在xml布局文件中由自定義屬性配置參數指定
 */
public class RoundImageView extends ImageView {
    private int mBorderThickness = 0;
    private Context mContext;
    private int defaultColor = 0xFFFFFFFF;
    // 如果只有其中一個有值，則只畫一個圓形邊框
    private int mBorderOutsideColor = 0;
    private int mBorderInsideColor = 0;
    // 控件默認長、寬
    private int defaultWidth = 0;
    private int defaultHeight = 0;
//構造方法，參數上下文
    public RoundImageView(Context context) {
        super(context);
        mContext = context;
    }

    public RoundImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
        mContext = context;
        setCustomAttributes(attrs);
    }

    public RoundImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        mContext = context;
        setCustomAttributes(attrs);
    }

    private void setCustomAttributes(AttributeSet attrs) {
        TypedArray a = mContext.obtainStyledAttributes(attrs, R.styleable.roundedimageview);
        mBorderThickness = a.getDimensionPixelSize(R.styleable.roundedimageview_border_thickness, 0);
        mBorderOutsideColor = a.getColor(R.styleable.roundedimageview_border_outside_color, defaultColor);
        mBorderInsideColor = a.getColor(R.styleable.roundedimageview_border_inside_color, defaultColor);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        Drawable drawable = getDrawable();
        if (drawable == null) {
            return;
        }
        if (getWidth() == 0 || getHeight() == 0) {
            return;
        }
        this.measure(0, 0);
        if (drawable.getClass() == NinePatchDrawable.class)
            return;
        Bitmap b = ((BitmapDrawable) drawable).getBitmap();
        Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);
        if (defaultWidth == 0) {
            defaultWidth = getWidth();
        }
        if (defaultHeight == 0) {
            defaultHeight = getHeight();
        }
        int radius = 0;
        if (mBorderInsideColor != defaultColor && mBorderOutsideColor != defaultColor) {// 定義畫兩個邊框，分別為外圓邊框和內圓邊框
            radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - 2 * mBorderThickness;
            // 畫內圓
            drawCircleBorder(canvas, radius + mBorderThickness / 2, mBorderInsideColor);
            // 畫外圓
            drawCircleBorder(canvas, radius + mBorderThickness + mBorderThickness / 2, mBorderOutsideColor);
        } else if (mBorderInsideColor != defaultColor && mBorderOutsideColor == defaultColor) {// 定義畫一個邊框
            radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - mBorderThickness;
            drawCircleBorder(canvas, radius + mBorderThickness / 2, mBorderInsideColor);
        } else if (mBorderInsideColor == defaultColor && mBorderOutsideColor != defaultColor) {// 定義畫一個邊框
            radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - mBorderThickness;
            drawCircleBorder(canvas, radius + mBorderThickness / 2, mBorderOutsideColor);
        } else {// 沒有邊框
            radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2;
        }
        Bitmap roundBitmap = getCroppedRoundBitmap(bitmap, radius);
        canvas.drawBitmap(roundBitmap, defaultWidth / 2 - radius, defaultHeight / 2 - radius, null);
    }

    /**
     * 獲取裁剪后的圓形圖片
     *
     * @param
     */
//    radius半徑
    public Bitmap getCroppedRoundBitmap(Bitmap bmp, int radius) {
        Bitmap scaledSrcBmp;
        int diameter = radius * 2;
        // 為了防止寬高不相等，造成圓形圖片變形，因此截取長方形中處于中間位置最大的正方形圖片
        int bmpWidth = bmp.getWidth();
        int bmpHeight = bmp.getHeight();
        int squareWidth = 0, squareHeight = 0;
        int x = 0, y = 0;
        Bitmap squareBitmap;
        if (bmpHeight > bmpWidth) {// 高大于寬
            squareWidth = squareHeight = bmpWidth;
            x = 0;
            y = (bmpHeight - bmpWidth) / 2;
            // 截取正方形圖片
            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth, squareHeight);
        } else if (bmpHeight < bmpWidth) {// 寬大于高
            squareWidth = squareHeight = bmpHeight;
            x = (bmpWidth - bmpHeight) / 2;
            y = 0;
            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth, squareHeight);
        } else {
            squareBitmap = bmp;
        }
        if (squareBitmap.getWidth() != diameter || squareBitmap.getHeight() != diameter) {
            scaledSrcBmp = Bitmap.createScaledBitmap(squareBitmap, diameter, diameter, true);
        } else {
            scaledSrcBmp = squareBitmap;
        }
        Bitmap output = Bitmap.createBitmap(scaledSrcBmp.getWidth(),
                scaledSrcBmp.getHeight(),
                Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(output);

        Paint paint = new Paint();
        Rect rect = new Rect(0, 0, scaledSrcBmp.getWidth(), scaledSrcBmp.getHeight());

        paint.setAntiAlias(true);
        paint.setFilterBitmap(true);
        paint.setDither(true);
        canvas.drawARGB(0, 0, 0, 0);
        canvas.drawCircle(scaledSrcBmp.getWidth() / 2,
                scaledSrcBmp.getHeight() / 2,
                scaledSrcBmp.getWidth() / 2,
                paint);
        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
        canvas.drawBitmap(scaledSrcBmp, rect, rect, paint);
        bmp = null;
        squareBitmap = null;
        scaledSrcBmp = null;
        return output;
    }

    /**
     * 邊緣畫圓
     */
    private void drawCircleBorder(Canvas canvas, int radius, int color) {
        Paint paint = new Paint();
            /* 去鋸齒 */
        paint.setAntiAlias(true);
        paint.setFilterBitmap(true);
        paint.setDither(true);
        paint.setColor(color);
            /* 設置paint的    style    為STROKE：空心 */
        paint.setStyle(Paint.Style.STROKE);
            /* 設置paint的外框寬度 */
        paint.setStrokeWidth(mBorderThickness);
        canvas.drawCircle(defaultWidth / 2, defaultHeight / 2, radius, paint);
    }
}

使用時非常簡單，直接在布局中調用自定義的類

activity_main.xml，這里要注意的是，第二個是帶有邊框的，效果圖如上

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:imagecontrol="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.ceshi.MainActivity">

    <Button
        android:id="@+id/aaa"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="點擊設置頭像" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <com.example.ceshi.RoundImageView
            android:id="@+id/image"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content" />
        <!-- border_outside_color 外部圓圈的顏色 -->
        <!-- border_inside_color 內部部圓圈的顏色 -->
        <!-- border_thickness 外圓和內圓的寬度 -->
        <com.example.ceshi.RoundImageView
            android:id="@+id/img2"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            imagecontrol:border_inside_color="#bc0978"
            imagecontrol:border_outside_color="#ba3456"
            imagecontrol:border_thickness="1dp" />
    </LinearLayout>

打開圖庫選取圖片，截取圖片和設置圖片在MainActivity.class中實現

MainActivity.class

public class MainActivity extends AppCompatActivity {
    private Button bt;
    private static final int PHOTO_REQUEST_GALLERY = 2;// 從相冊中選擇
    private static final int PHOTO_REQUEST_CUT = 3;// 結果
    private ImageView photo,photo2;
    private File tempFile;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        photo= (ImageView) findViewById(R.id.image);
        photo2= (ImageView) findViewById(R.id.img2);

        bt = (Button) findViewById(R.id.aaa);
        bt.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
//                Intent intent=new Intent(Intent.ACTION_PICK);
//                intent.setType("image/*");
//                startActivityForResult(intent,PHOTO_REQUEST_GALLERY);
                // 激活系統圖庫，選擇一張圖片
                Intent intent = new Intent(Intent.ACTION_PICK);
                intent.setType("image/*");
                // 開啟一個帶有返回值的Activity，請求碼為PHOTO_REQUEST_GALLERY
                startActivityForResult(intent, PHOTO_REQUEST_GALLERY);
            }
        });
    }

    /*
            * 剪切圖片
            */
    private void crop(Uri uri) {
        // 裁剪圖片意圖
        Intent intent = new Intent("com.android.camera.action.CROP");
        intent.setDataAndType(uri, "image/*");
        intent.putExtra("crop", "true");
        // 裁剪框的比例，1：1
        intent.putExtra("aspectX", 1);
        intent.putExtra("aspectY", 1);
        // 裁剪后輸出圖片的尺寸大小
        intent.putExtra("outputX", 250);
        intent.putExtra("outputY", 250);

        intent.putExtra("outputFormat", "JPEG");// 圖片格式
        intent.putExtra("noFaceDetection", true);// 取消人臉識別
        intent.putExtra("return-data", true);
        // 開啟一個帶有返回值的Activity，請求碼為PHOTO_REQUEST_CUT
        startActivityForResult(intent, PHOTO_REQUEST_CUT);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == PHOTO_REQUEST_GALLERY) {
            // 從相冊返回的數據
            if (data != null) {
                // 得到圖片的全路徑
                Uri uri = data.getData();
                crop(uri);
            }
        } else if (requestCode == PHOTO_REQUEST_CUT) {
            // 從剪切圖片返回的數據
            if (data != null) {
                Bitmap bitmap = data.getParcelableExtra("data");
                photo.setImageBitmap(bitmap);
                photo2.setImageBitmap(bitmap);
            }
            try {
                // 將臨時文件刪除
                tempFile.delete();
            } catch (Exception e) {
                e.printStackTrace();
            }

        }
        super.onActivityResult(requestCode, resultCode, data);

    }
}

以上就可以實現自定義控件，設置圓形頭像

來自：http://www.cnblogs.com/dingxiansen/p/6135795.html