android自定义view实现股票趋势图

package com.example.customview1406_03; import java.util.ArrayList; import java.util.HashMap; import android.content.Context; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Rect; import android.util.AttributeSet; import android.view.View; public class CustomView extends View { int viewWidth, viewHeight; ArrayList<HashMap<String, String>> list; int maxPrice; public void setData(ArrayList<HashMap<String, String>> list) { if (list != null) { this.list = list; for (int i = 0; i < list.size(); i++) { HashMap<String, String> map = list.get(i); String strPrice = map.get("price"); int intPrice = Integer.parseInt(strPrice); if (intPrice > maxPrice) { maxPrice = intPrice; } } } else { this.list = new ArrayList<HashMap<String, String>>(); } } public CustomView(Context context, AttributeSet attrs) { super(context, attrs); // TODO Auto-generated constructor stub } @Override protected void onDraw(Canvas canvas) { try { Rect rect = new Rect(0, 0, viewWidth, viewHeight); Paint paint = new Paint(); paint.setColor(0xFF000000); // 画背景 canvas.drawRect(rect, paint); // 40 代表最后一个时间的宽度,字符串的宽度跟字号，字体有关，应该用android提供的api去得一个字符串的宽度 int gap = (viewWidth - 40) / (list.size() - 1); // 画时间 paint.setColor(0xFFFFFFFF); paint.setTextSize(20); // 时间的高度 int timeHeight = 40; int preiceHeight = viewHeight - timeHeight; for (int i = 0; i < list.size(); i++) { // 取到时间 HashMap<String, String> map = list.get(i); String time = map.get("time"); int timeLeft = i * gap; canvas.drawText(time, timeLeft, viewHeight, paint); // 画价格 String strPrice = map.get("price"); int intPrice = Integer.parseInt(strPrice); int priceTop = (intPrice * preiceHeight / maxPrice); // 最少的价格显示在最上面，应该显示在最下面 priceTop = preiceHeight - priceTop; priceTop = priceTop + 20;// 20是价格的高度 canvas.drawText(strPrice, timeLeft, priceTop, paint); if (i < list.size() - 1) { // 画线 int startX = timeLeft; int startY = priceTop; int endX = 0, endY = 0; // 下一个价格的坐标 endX = (i + 1) * gap; String strNextPrice = list.get(i + 1).get("price"); int intNextPrice = Integer.parseInt(strNextPrice); endY = (intNextPrice * preiceHeight) / maxPrice; endY = preiceHeight - endY; endY = endY + 20; canvas.drawLine(startX, startY, endX, endY, paint); } } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { // TODO Auto-generated method stub viewHeight = h; viewWidth = w; super.onSizeChanged(w, h, oldw, oldh); } }