손 으로 안 드 로 이 드 사용자 정의 케이크 모양 그림 을 가르쳐 드릴 게 요.

관례 대로 먼저 효과 도 를 올리다.

이 예 를 통 해 당신 은 무엇 을 배 울 수 있 습 니까?
     Paint 에 대해 깊이 이해 하고 떡 그림,사각형,문자 등 을 그립 니 다.
     canvas API 에 대한 파악 을 강화 하고 사용자 정의 View 에 대한 파악 을 강화 합 니 다.
다음은 간단 한 떡 그림 그리 기 과정 을 7 단계 로 나 누 어 완성 하 겠 습 니 다.
1.다시 보기 의 구조 방법

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

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

 public PieView(Context context, AttributeSet attrs, int defStyleAttr) {
 super(context, attrs, defStyleAttr);
 init();
 }

 private void init() {
 mPieColorList = new ArrayList<>();
 mPieValue = new ArrayList<>();
 mStringList = new ArrayList<>();
 mPaint = new Paint();
 mMaxString = "";
 mPaint.setColor(Color.BLACK);
 mPaint.setStrokeWidth(10);//    
 mPaint.setAntiAlias(true);//   
 }

2.도형 그리 기

/**
 *     
 *
 * @param canvas
 * @param amount
 */
 private void drawPie(Canvas canvas, int amount) {
 mPaint.setColor(mCurrentColor);
 mPaint.setStyle(Paint.Style.FILL);
 int angle = (int) (360f * amount / mMaxValue);
 Log.d("angle", "drawPie: " + angle);
 canvas.drawArc(oval, mStartAngle, angle, true, mPaint);
 mStartAngle += angle;
 }

 /**
 *     
 *
 * @param canvas
 */
 private void drawRect(Canvas canvas) {
 if (mCurrentIndex == 0) {
  rect = new RectF(mRectMarginLeft, mPadding, mRectMarginLeft + RECT_WIDTH, mPadding + RECT_WIDTH);
  canvas.drawRect(rect, mPaint);
 } else {
  rect = new RectF(mRectMarginLeft, (mCurrentIndex) * TEXT_VERTICAL_PADDING + mPadding, mRectMarginLeft + RECT_WIDTH, (mCurrentIndex) * TEXT_VERTICAL_PADDING + mPadding + RECT_WIDTH);
  canvas.drawRect(rect, mPaint);
 }
 }

 /**
 *     
 *
 * @param canvas
 * @param text
 */
 private void drawText(Canvas canvas, String text) {
 mPaint.setColor(TEXT_COLOR);
 if (mCurrentIndex == 0) {
  canvas.drawText(text, mTextMarginLeft, mPadding + TEXT_SIZE * 0.8f - 5, mPaint);
 } else {
  canvas.drawText(text, mTextMarginLeft, (mCurrentIndex) * TEXT_VERTICAL_PADDING + mPadding + TEXT_SIZE * 0.8f - 5, mPaint);
 }
 }

3.Pie 실체 류

public class Pie {
 public int PieColor;
 public int PieValue;
 public String PieString;

 public Pie(int pieValue, String pieString, int pieColor) {
 this.PieValue = pieValue;
 this.PieString = pieString;
 this.PieColor = pieColor;
 }
}

4.xml 참조

 <aikaifa.canvas.widget.PieView
 android:layout_width="match_parent"
 android:layout_height="200dp"
 android:id="@+id/PieView" />

5.데이터 채 우기

public class MainActivity extends Activity {
 private ArrayList<Pie> pieArrayList = new ArrayList<>();
 private String[] arr = {"C#", "C", "C++", "JAVA", "JavaScript", "Object-C"};
 private int[] pre = {20, 30, 10, 10, 10, 20};
 private PieView pieView;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);

 pieView = (PieView) findViewById(R.id.PieView);
 int[] pieColor = {getResources().getColor(R.color.blue), getResources().getColor(R.color.red), getResources().getColor(R.color.gray_dark),
  getResources().getColor(R.color.dark), getResources().getColor(R.color.colorPrimary), getResources().getColor(R.color.black_alpha_light)};
 for (int i = 0; i < arr.length; i++) {
  Pie pie = new Pie(pre[i], arr[i], pieColor[i]);
  pieArrayList.add(pie);
 }
 pieView.SetPie(pieArrayList);
 }

}

6.완전한 PieView

public class PieView extends View {

 private Paint mPaint;
 //        
 private final int PIE_RECT_PADDING = getResources().getDimensionPixelSize(R.dimen.pie_rect_padding);
 //     
 private final int RECT_WIDTH = getResources().getDimensionPixelSize(R.dimen.rect_width);
 //        
 private final int RECT_TEXT_PADDING = getResources().getDimensionPixelSize(R.dimen.rect_text_padding);
 //     
 private final int TEXT_SIZE = getResources().getDimensionPixelSize(R.dimen.text_size);
 //       
 private final int TEXT_VERTICAL_PADDING = getResources().getDimensionPixelSize(R.dimen.text_vertical_padding);
 //      
 private final int TEXT_COLOR = getResources().getColor(R.color.gray_dark);
 //          
 private float mPadding;
 //     
 private int mPieRadios;
 //       
 private int mMaxValue;
 //       
 private int mStartAngle;
 //     
 private int mTextWidth;
 //    
 private int mControlHalfHeight;
 //    
 private int mCurrentIndex;
 //   
 private int mRectMarginLeft;
 private int mTextMarginLeft;
 //    
 private int mCurrentColor;
 //    
 private RectF oval;
 //      
 private String mMaxString;

 private List<Integer> mPieColorList;
 private List<Integer> mPieValue;
 private List<String> mStringList;
 private ArrayList<Pie> mPieArrayList;

 private RectF rect;

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

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

 public PieView(Context context, AttributeSet attrs, int defStyleAttr) {
 super(context, attrs, defStyleAttr);
 init();
 }

 private void init() {
 mPieColorList = new ArrayList<>();
 mPieValue = new ArrayList<>();
 mStringList = new ArrayList<>();
 mPaint = new Paint();
 mMaxString = "";
 mPaint.setColor(Color.BLACK);
 mPaint.setStrokeWidth(10);//    
 mPaint.setAntiAlias(true);//   
 }

 @Override
 protected void onSizeChanged(int width, int height, int oldWidth, int oldHeight) {
 super.onSizeChanged(width, height, oldWidth, oldHeight);
 mTextWidth = (int) mPaint.measureText(mMaxString);
 mControlHalfHeight = height / 2;
 //    
 mPieRadios = mControlHalfHeight - 5;
 //      
 int contentWidth = mPieRadios * 2 + PIE_RECT_PADDING + RECT_WIDTH + RECT_TEXT_PADDING + mTextWidth;
 //      
 int contentMarginLeft = (width - contentWidth) / 2;
 //      
 mRectMarginLeft = contentMarginLeft + mPieRadios * 2 + PIE_RECT_PADDING;
 //      
 mTextMarginLeft = mRectMarginLeft + RECT_WIDTH + RECT_TEXT_PADDING;
 //          
 mPadding = height / mPieArrayList.size() * 0.8f;
 oval = new RectF(contentMarginLeft, mControlHalfHeight - mPieRadios,
  contentMarginLeft + mPieRadios * 2, mControlHalfHeight + mPieRadios);
 }

 /**
 * @param pieArrayList
 */
 public void SetPie(ArrayList<Pie> pieArrayList) {
 mPieArrayList = pieArrayList;
 for (Pie mPie : mPieArrayList) {
  mPieColorList.add(mPie.PieColor);
  mPieValue.add(mPie.PieValue);
  mStringList.add(mPie.PieString);
  if (mMaxString.length() > mPie.PieString.length())
  mMaxString = mPie.PieString;
 }

 //  postInvalidate             
 postInvalidate();
 }

 @Override
 protected void onDraw(Canvas canvas) {
 super.onDraw(canvas);

 mStartAngle = -90;
 mCurrentIndex = 0;
 mMaxValue = 100;
 mPaint.setStyle(Paint.Style.FILL);

 for (int i = 0; i < mPieValue.size(); i++) {
  mCurrentColor = mPieColorList.get(mCurrentIndex);
  Log.i("mCurrentColor", "onDraw: " + mCurrentColor);
  drawPie(canvas, mPieValue.get(mCurrentIndex));
  drawRect(canvas);
  drawText(canvas, mStringList.get(mCurrentIndex));
  mCurrentIndex++;
 }
 }

 /**
 *     
 *
 * @param canvas
 * @param amount
 */
 private void drawPie(Canvas canvas, int amount) {
 mPaint.setColor(mCurrentColor);
 mPaint.setStyle(Paint.Style.FILL);
 int angle = (int) (360f * amount / mMaxValue);
 Log.d("angle", "drawPie: " + angle);
 canvas.drawArc(oval, mStartAngle, angle, true, mPaint);
 mStartAngle += angle;
 }

 /**
 *     
 *
 * @param canvas
 */
 private void drawRect(Canvas canvas) {
 if (mCurrentIndex == 0) {
  rect = new RectF(mRectMarginLeft, mPadding, mRectMarginLeft + RECT_WIDTH, mPadding + RECT_WIDTH);
  canvas.drawRect(rect, mPaint);
 } else {
  rect = new RectF(mRectMarginLeft, (mCurrentIndex) * TEXT_VERTICAL_PADDING + mPadding, mRectMarginLeft + RECT_WIDTH, (mCurrentIndex) * TEXT_VERTICAL_PADDING + mPadding + RECT_WIDTH);
  canvas.drawRect(rect, mPaint);
 }
 }

 /**
 *     
 *
 * @param canvas
 * @param text
 */
 private void drawText(Canvas canvas, String text) {
 mPaint.setColor(TEXT_COLOR);
 if (mCurrentIndex == 0) {
  canvas.drawText(text, mTextMarginLeft, mPadding + TEXT_SIZE * 0.8f - 5, mPaint);
 } else {
  canvas.drawText(text, mTextMarginLeft, (mCurrentIndex) * TEXT_VERTICAL_PADDING + mPadding + TEXT_SIZE * 0.8f - 5, mPaint);
 }
 }

 @Override
 public boolean onTouchEvent(MotionEvent event) {
 if (event.getAction() == MotionEvent.ACTION_DOWN) {
  float x = event.getX();
  float y = event.getY();
  Log.e("",x+"-----------");
 }
 return true;
 }
}

7.기타 서류
colors.xml

  <color name="dark">#0097a7</color>
  <color name="grey">#e0e0e0</color>
  <color name="gray_dark">#666666</color>
  <color name="black_alpha_light">#3c3f41</color>
  <color name="black_light">#383838</color>
  <color name="blue">#03a9f4</color>
  <color name="red">#ff4081</color>

dimens.xml

  <dimen name="fab_margin">16dp</dimen>
  <dimen name="pie_rect_padding">30dp</dimen>
  <dimen name="rect_text_padding">6dp</dimen>
  <dimen name="rect_width">15dp</dimen>
  <dimen name="text_size">18sp</dimen>
  <dimen name="text_vertical_padding">25dp</dimen>

총결산
자,이렇게 간단 한 떡 그림 을 그리 면 완성 된다.이 글 의 내용 이 안 드 로 이 드 개발 자 여러분 에 게 도움 이 되 기 를 바 랍 니 다.궁금 한 점 이 있 으 면 댓 글 을 남 겨 주 십시오.