在android中的餅圖上單擊事件

Question

我已經使用畫布繪製餅圖.. 餅圖中有大約10個弧..我想在每個弧上執行點擊事件。 有沒有辦法做到這一點？或者其他方式？

這是我的餅圖..

MyView.java

package android.piechart; 
import java.util.ArrayList; 
import android.content.Context; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Paint; 
import android.graphics.RectF; 
import android.util.AttributeSet; 
import android.util.Log; 
import android.view.View; 

public class MyView extends View { 

private Paint p; 
private int startX; 
private int startY; 
private int radius; 
private ArrayList<Integer> colors; 
private ArrayList<Integer> values; 

public MyView(Context context, AttributeSet attrs) { 
    super(context, attrs); 
    p = new Paint(); 
    p.setColor(Color.BLUE); 
    p.setAntiAlias(true); 

    colors = new ArrayList<Integer>(); 
    values = new ArrayList<Integer>(); 

    startX = 320/4; 
    startY = 480/8; 
    radius = 320/2; 

    colors.add(Color.GREEN); 
    colors.add(Color.CYAN); 
    colors.add(Color.MAGENTA); 
    colors.add(Color.BLUE); 
    colors.add(Color.RED); 

    values.add(0); 
    values.add(1); 
    values.add(3); 
    values.add(0); 
    values.add(2); 

} 

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

    Log.e("", "onDraw() is called..."); 

    float offset = 0; 
    float sum = 0; 
    for (int a = 0; a < values.size(); a++) { 
     sum += values.get(a); 
    } 

    float angle = (float) (360/sum); 

    Log.e("angle", "" + angle); 

    RectF rectF = new RectF(); 
    rectF.set(getStartX(), getStartY(), getStartX() + getRadius(), 
      getStartY() + getRadius()); 

    for (int i = 0; i < values.size(); i++) { 

     p.setColor(colors.get(i)); 

     if (i == 0) { 
      canvas.drawArc(rectF, 0, values.get(i) * angle, true, p); 
     } else { 
      canvas.drawArc(rectF, offset, values.get(i) * angle, true, p); 
     } 

     offset += (values.get(i) * angle); 
    } 

    canvas.save(); 
} 

public int getStartX() { 
    return startX; 
} 

public void setStartX(int startX) { 
    this.startX = startX; 
} 

public int getStartY() { 
    return startY; 
} 

public void setStartY(int startY) { 
    this.startY = startY; 
} 

public int getRadius() { 
    return radius; 
} 

public void setRadius(int radius) { 
    this.radius = radius; 
} 

public ArrayList<Integer> getColors() { 
    return colors; 
} 

public void setColors(ArrayList<Integer> colors) { 
    this.colors = colors; 
} 

public ArrayList<Integer> getValues() { 
    return values; 
} 

public void setValues(ArrayList<Integer> values) { 
    this.values = values; 
} 
} 

在此先感謝..

Answer 1

我解決我的問題我自己...

MyView.java

public class MyView extends View { 

private Paint p; 
private int startX; 
private int startY; 
private int radius; 
private ArrayList<Integer> colors; 
private ArrayList<Float> values; 
Bitmap bitmap; 
Context mContext; 

public MyView(Context context, AttributeSet attrs) { 
    super(context, attrs); 

    mContext = context; 

    p = new Paint(); 
    p.setAntiAlias(true); 

    colors = new ArrayList<Integer>(); 
    values = new ArrayList<Float>(); 

    startX = 320/4; 
    startY = 480/8; 
    radius = 320/2; 

    colors.add(Color.GREEN); 
    colors.add(Color.CYAN); 
    colors.add(Color.MAGENTA); 
    colors.add(Color.BLUE); 
    colors.add(Color.RED); 

    values.add(5f); 
    values.add(1f); 
    values.add(3f); 
    values.add(5f); 
    values.add(2f); 

} 

@Override 
protected void onDraw(Canvas canvas) { 
    super.onDraw(canvas); 
    bitmap = Bitmap.createBitmap(canvas.getWidth(), canvas.getHeight(), 
      Bitmap.Config.ARGB_8888); 

    Canvas c = new Canvas(bitmap); 

    Log.e("", "onDraw() is called..."); 

    float offset = 0; 
    float sum = 0; 
    for (int a = 0; a < values.size(); a++) { 
     sum += values.get(a); 
    } 

    float angle = (float) (360/sum); 

    Log.e("angle", "" + angle); 

    RectF rectF = new RectF(); 
    rectF.set(getStartX(), getStartY(), getStartX() + getRadius(), 
      getStartY() + getRadius()); 

    for (int i = 0; i < values.size(); i++) { 

     p.setColor(colors.get(i)); 

     if (i == 0) { 
      canvas.drawArc(rectF, 0, values.get(i) * angle, true, p); 
      c.drawArc(rectF, 0, values.get(i) * angle, true, p); 
     } else { 
      canvas.drawArc(rectF, offset, values.get(i) * angle, true, p); 
      c.drawArc(rectF, offset, values.get(i) * angle, true, p); 
     } 

     offset += (values.get(i) * angle); 
    } 

    canvas.save(); 

} 

@Override 
public boolean onTouchEvent(MotionEvent event) { 

    int color = bitmap.getPixel((int) event.getX(), (int) event.getY()); 

    Log.e("", "" + color); 

    if (colors.contains(color)) { 
     Log.e("", "is matching"); 
     if (color == Color.RED) { 
      Toast.makeText(mContext, "Is Red", Toast.LENGTH_SHORT).show(); 
     } 

     if (color == Color.CYAN) { 
      Toast.makeText(mContext, "Is Cyan", Toast.LENGTH_SHORT).show(); 
     } 

     if (color == Color.MAGENTA) { 
      Toast.makeText(mContext, "Is MAGENTA", Toast.LENGTH_SHORT) 
        .show(); 
     } 
     if (color == Color.BLUE) { 
      Toast.makeText(mContext, "Is BLUE", Toast.LENGTH_SHORT).show(); 
     } 
     if (color == Color.GREEN) { 
      Toast.makeText(mContext, "Is GREEN", Toast.LENGTH_SHORT).show(); 
     } 
    } 

    return super.onTouchEvent(event); 
} 

public int getStartX() { 
    return startX; 
} 

public void setStartX(int startX) { 
    this.startX = startX; 
} 

public int getStartY() { 
    return startY; 
} 

public void setStartY(int startY) { 
    this.startY = startY; 
} 

public int getRadius() { 
    return radius; 
} 

public void setRadius(int radius) { 
    this.radius = radius; 
} 

public ArrayList<Integer> getColors() { 
    return colors; 
} 

public void setColors(ArrayList<Integer> colors) { 
    this.colors = colors; 
} 

public ArrayList<Float> getValues() { 
    return values; 
} 

public void setValues(ArrayList<Float> values) { 
    this.values = values; 
} 

} 

我希望這是有用的人......

piechart

Answer 2

如果你已經使用了Canvas，你可能要參考其底層Bitmap。你可以使用Bitmap.getPixel(int x, int y)並測試它返回到決定點擊是哪個部分的顏色。

否則，你必須做手工計算，以找出哪些楔包含x，你點擊的y座標。