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[转]通过创建一个位图的XY Chart来学习Android绘图类Rect,Paint,Bitmap,Canvas（附源码）...

發(fā)布時(shí)間：2023/12/15 Android 16 豆豆

生活随笔收集整理的這篇文章主要介紹了 [转]通过创建一个位图的XY Chart来学习Android绘图类Rect,Paint,Bitmap,Canvas（附源码）... 小編覺得挺不錯(cuò)的,現(xiàn)在分享給大家,幫大家做個(gè)參考.

本文轉(zhuǎn)自：http://www.cnblogs.com/salam/archive/2010/11/10/1873437.html

　繪制一個(gè)XY集是一種很常見的任務(wù),基于Android平臺的繪制很簡單，它讓所有的GUI在XML中定義的（雖然它也可以通過代碼創(chuàng)建）模型是相當(dāng)不錯(cuò)的。大部分的圖形處理一個(gè)樣本查看，但在大多數(shù)情況下，圖應(yīng)該是一個(gè)部分的實(shí)施走上屏幕布局XML定義為一所以在這里展示我們ImageView布局對象。

　　在Android環(huán)境中，有一整套程序的圖形通常是位圖實(shí)現(xiàn)像素，Canvas是用來繪制位圖的畫布，通過這一點(diǎn)我們可以得出元（文字，線條等）它描述了漆的顏色，款式等。

?下面是效果圖

　　圖形界面我們通過Xml定義。

　　1.XML的GUI布局?

<?xml version="1.0" encoding="utf-8"?>

<TableLayout

??? xmlns:android="http://schemas.android.com/apk/res/android"
??? android:layout_height="fill_parent"
??? android:layout_width="fill_parent"
??? android:background="#4B088A">
?
??? <TableRow android:layout_width="fill_parent"
??? android:layout_height="wrap_content"
???? android:padding="20px">
??
???? <TextView?
android:id="@+id/some"
??? android:layout_width="fill_parent"
??? android:layout_height="wrap_content"
??? android:text="Some layout? items here"
??? android:layout_marginLeft="10px"
??? android:layout_marginRight="10px"
??? android:textColor="#ff8000"
??? android:textStyle="bold"
??? />

??? </TableRow>

<View????
? android:layout_width="fill_parent"
android:layout_height="1dip"
android:background="#FFE6E6E6"
/>
???
??? <TableRow>

??? <ImageView?
android:id="@+id/testy_img"
android:layout_marginLeft="20px"
android:padding="20px"
??? />

?? </TableRow>

<View????
? android:layout_width="fill_parent"
android:layout_height="1dip"
android:background="#FFE6E6E6" />

??? <TableRow android:layout_width="fill_parent"

??? android:layout_height="wrap_content"
???? android:padding="20px">

???? <TextView?
android:id="@+id/more"
??? android:layout_width="fill_parent"
??? android:layout_height="wrap_content"
??? android:text="More layout items here"
??? android:layout_marginLeft="10px"
??? android:layout_marginRight="10px"
?? android:textColor="#ff8000"
??? android:textStyle="bold"
??? />

??? </TableRow>

</TableLayout>

這個(gè)布局文件是TableLayout布局，它定義了三行，行之間通過一條線割開

2.圖表的實(shí)現(xiàn)

　　為了實(shí)現(xiàn)我們的圖表，我們首先創(chuàng)建一個(gè)位圖，然后關(guān)聯(lián)到我們的布局文件，有了位圖，我們就可以繪制圖表，做縮放，色彩和數(shù)據(jù)顯示?等效果。

　　2.1繪制位圖

　　首先我們使布局連接到XML對象的，那么我們創(chuàng)建位圖。我們通過quicky_XY方法來實(shí)現(xiàn)所有的繪制，最后顯示在屏幕上。

public void onCreate(Bundle savedInstanceState) {
??super.onCreate(savedInstanceState);
??setContentView(R.layout.main);

??ImageView image = (ImageView) findViewById(R.id.testy_img);

??Bitmap emptyBmap = Bitmap.createBitmap(250, 200, Config.ARGB_8888);

??int width = emptyBmap.getWidth();
??int height = emptyBmap.getHeight();
??Bitmap charty = Bitmap.createBitmap(width, height,
????Bitmap.Config.ARGB_8888);

??charty = quicky_XY(emptyBmap);

??image.setImageBitmap(charty);
?}

　　2.2繪制網(wǎng)格

　　有了位圖后，將它與Canvas相關(guān)聯(lián)

　　Canvas canvas = new Canvas(bitmap)

然后將所有的元素繪制到Canvas上，我們需要定義一些用于放置標(biāo)簽和數(shù)據(jù)點(diǎn)空間的網(wǎng)格。

public static void draw_the_grid(Canvas this_g, Vector these_labels) {
??double rounded_max = 0.0;
??double rounded_min = 0.0;
??double rounded_max_temp;
??Object curElt;
??String[] cur_elt_array;
??int left_margin_d, right_margin_d;

??if (draw_only_this_idx == -1)
???curElt = these_labels.elementAt(0); // default it to 1st one if non
??// set
??else
???curElt = these_labels.elementAt(draw_only_this_idx); // now just the
??// 1st elt

??cur_elt_array = (String[]) curElt;

??rounded_max = get_ceiling_or_floor(
????Double.parseDouble(cur_elt_array[2]), true);
??rounded_min = get_ceiling_or_floor(
????Double.parseDouble(cur_elt_array[3]), false);

??// ok so now we have the max value of the set just get a cool ceiling
??// and we go on
??final Paint paint = new Paint();
??paint.setTextSize(15);

??left_margin_d = getCurTextLengthInPixels(paint, Double
????.toString(rounded_max));
??// keep the position for later drawing -- leave space for the legend
??int p_height = 170;
??int p_width = 220;
??int[] tmp_draw_sizes = { 2 + left_margin_d, 25,
????p_width - 2 - left_margin_d, p_height - 25 - 5 };
??drawSizes = tmp_draw_sizes; // keep it for later processing

??// with the mzrgins worked out draw the plotting grid
??paint.setStyle(Paint.Style.FILL);
??paint.setColor(Color.WHITE);

??// Android does by coords
??this_g
????.drawRect(drawSizes[0], drawSizes[1], drawSizes[0]
??????+ drawSizes[2], drawSizes[1] + drawSizes[3], paint);

??paint.setColor(Color.GRAY);

??// finally draw the grid

??paint.setStyle(Paint.Style.STROKE);
??this_g
????.drawRect(drawSizes[0], drawSizes[1], drawSizes[0]
??????+ drawSizes[2], drawSizes[1] + drawSizes[3], paint);

??for (int i = 1; i < 5; i++) {
???this_g.drawLine(drawSizes[0],
?????drawSizes[1] + (i * drawSizes[3] / 5), drawSizes[0]
???????+ drawSizes[2], drawSizes[1]
???????+ (i * drawSizes[3] / 5), paint);
???this_g.drawLine(drawSizes[0] + (i * drawSizes[2] / 5),
?????drawSizes[1], drawSizes[0] + (i * drawSizes[2] / 5),
?????drawSizes[1] + drawSizes[3], paint);
??}

??// good for one value
??print_axis_values_4_grid(this_g, cur_elt_array[1], Double
????.toString(rounded_max), Double.toString(rounded_min),
????cur_elt_array[0], 2, 0);

?} // --- end of draw_grid ---

　　2.3繪圖和縮放

　　　　這些數(shù)據(jù)點(diǎn)需要一到屏幕上的坐標(biāo)數(shù)據(jù)范圍正確的映射遍歷數(shù)據(jù)點(diǎn)和調(diào)用drawLine接連兩個(gè)點(diǎn)會完成我們的圖表。數(shù)據(jù)點(diǎn)通過數(shù)據(jù)為載體，現(xiàn)在將調(diào)用plot_array_list

private static Point? scale_point(int this_x , double this_y? , Point drawPoint ,
??????????? int scr_x? , int scr_y? , int scr_width? , int src_height? ,
??????????? double maxX? , double minX? , double? maxY? , double minY? )
?????? {
?????????? int temp_x, temp_y;
?????????? Point temp = new Point();??
??????????
?????????? if (maxY == minY)? //skip bad data
?????????????? return null;

?????????? //don't touch it if is nothing
?????????? try
?????????? {
?????????????????? temp_x = scr_x + (int)( ((double)this_x - minX) *
((double)scr_width / (maxX - minX)) );
?????????????????? temp_y = scr_y + (int)( (maxY - this_y) *
((double)src_height / (maxY - minY)) );
???????????????
?????????????????? temp.x = temp_x;
?????????????????? temp.y= temp_y;
?????????????????? drawPoint = temp;
?????????? }
?????????? catch? (Exception e)
?????????? {
???????
????????????? return (null);
?????????? }
??????????
?????????? return temp;
??????????
?????? } // --- end of scale_point --

??? public static boolean plot_array_list(Canvas this_g, Vector this_array_list ,
Vector these_labels , String this_title , int only_this_idx )
??? {
???????????? int idx;
???????????? int lRow ;
???????????? int nParms;
???????????? int? i, points_2_plot, shifted_idx ;
???????????? int prev_x, prev_y ;
???????????? int cur_x=0, cur_y=0 ;
???????????? //Dim ShowMarker As Object
???????????? Point cur_point = new Point();
??????????? cur_point.set(0,0);
????
???????????? double cur_maxX, cur_minX, cur_maxY=20, cur_minY=0, cur_rangeY;
???????????? int cur_start_x, cur_points_2_plot;
??
??????????? int POINTS_TO_CHANGE = 30;
??????????? double cur_OBD_val;
?
???????????? //Object curElt;?
???????????? String curElt;
???????????? String[] cur_elt_array;
???????????? Object curElt2;?
???????????? String[] cur_elt_array2;
????
???????????? final Paint paint = new Paint();

???????????? try // catch in this block for some thing
???????????? {??????
?????????????????? points_2_plot = this_array_list.size();
?????????????????? {
??????????????????????? cur_start_x = 0;
??????????????????????? cur_points_2_plot = points_2_plot;
??????????????????????? cur_maxX = cur_points_2_plot;
??????????????????????? cur_minX = 0;
?????????????????? }
?
?????????????????? //'Create the plot points for this series from the ChartPoints array:
??
?????????????????? curElt = (String)this_array_list.elementAt(0);
??????????????????
?????????????????? //the lines have to come out good
??????????????????? paint.setStyle(Paint.Style.STROKE);
//?????????????????
?????????????????? //for(? nParms = 0 ; nParms < cur_elt_array.length ; nParms++ )
?????????????????? nParms = only_this_idx;
?????????????????? {
???
?????????????????????? //get cur item labels
??????????????????????? curElt2 = these_labels.elementAt(nParms);
??????????????????????? cur_elt_array2? = (String[]) curElt2;
???????????????????????
??????????????????????? cur_maxY = get_ceiling_or_floor
(Double.parseDouble(cur_elt_array2[2]) , true);
??????????????????????? cur_minY = get_ceiling_or_floor
(Double.parseDouble(cur_elt_array2[3]) , false);
???????????????????????
??????????????????????? cur_points_2_plot = this_array_list.size();
??????????????????????? cur_maxX = cur_points_2_plot;
???
????????????????????? curElt = (String)this_array_list.elementAt(0);
????????????????????? cur_OBD_val = Double.parseDouble( curElt);
?????????????????????
????????????????????? cur_point = scale_point(0, cur_OBD_val, cur_point,
????????????????????????????? drawSizes[0], drawSizes[1], drawSizes[2], drawSizes[3],
????????????????????????????? cur_maxX, cur_minX, cur_maxY,
????? cur_minY); //'(CInt(curAxisValues.Mins(nParms - 2) / 5) + 1) * 5)
??????????????????????
?????????????????????? cur_x = cur_point.x;
?????????????????????? cur_y = cur_point.y;

?????????????????????? paint.setColor(Color.GREEN);
??????????????????????
????????????????????? // the point is only cool when samples are low
?????????????????????? if ( cur_points_2_plot < POINTS_TO_CHANGE)
???????????????????????? this_g.drawRect(cur_x-2, cur_y-2, cur_x-2 + 4,
cur_y-2+ 4 , paint);
??????????????????????
?????????????????????? prev_x = cur_x;
?????????????????????? prev_y = cur_y;

?????????????????????? //'go and plot point for this parm -- pont after the 1st one
?????????????????????? for (lRow = cur_start_x +1 ; lRow< cur_start_x +
cur_points_2_plot -1 ; lRow++)
?????????????????????? {???????
?????????????????????????? curElt = (String)this_array_list.elementAt(lRow);
??????????????????????????
?????????????????????????? cur_OBD_val = Double.parseDouble( curElt);
????????????????????????????????
??????????????????????????? //'work out an approx if cur Y values not avail(e.g. nothing)
?????????????????????????? // if (! (cur_elt_array[nParms ] == null ) )?? //skip bad one
???????????????????????????? if( cur_OBD_val == Double.NaN) continue;? //skip bad one
??????????????????????????? {?????????????????
??????
??????????????????????????????
??????????????????????????????? cur_point=scale_point(lRow, cur_OBD_val, cur_point,?
??????????????????????????????????? drawSizes[0], drawSizes[1],
drawSizes[2], drawSizes[3],
??????????????????????????????????? cur_maxX, cur_minX, cur_maxY, cur_minY);
???
??????????????????????????????? cur_x = cur_point.x;
??????????????????????????????? cur_y = cur_point.y;
???????????????????????????????
??????????????????????????????? if ( cur_points_2_plot < POINTS_TO_CHANGE)
?????????????????????????????????? this_g.drawRect(cur_x-2, cur_y-2, cur_x-2 +4,
cur_y-2 + 4, paint );

?????????????????????????????? this_g.drawLine( prev_x, prev_y, cur_x, cur_y, paint);
?????????????????????????????? prev_x = cur_x;
?????????????????????????????? prev_y = cur_y;
?????????????????????????
??????????????????????????? } // ' if end of this_array(lRow, nParms - 1)<> nothing
????????????????????????????????
?????????????????? } // end of for lrow
??????????????????????????????
?????????????? } // end of for nParmns

??????????? //this_g.invalidate();
??????????? return( true);
??????? }
??????? catch (Exception e)
??????? {
??????????? return( false);
??????? }

??? } // --- end of plot_array_list? --

Java完整代碼：

package com.wjq.chart;

import java.util.Vector;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Typeface;
import android.graphics.Bitmap.Config;
import android.graphics.Paint.FontMetrics;
import android.os.Bundle;
import android.widget.ImageView;

public class Main extends Activity {
?static int draw_only_this_idx = -1;
?static int[] drawSizes;

?@Override
?public void onCreate(Bundle savedInstanceState) {
??super.onCreate(savedInstanceState);
??setContentView(R.layout.main);

??ImageView image = (ImageView) findViewById(R.id.testy_img);

??Bitmap emptyBmap = Bitmap.createBitmap(250, 200, Config.ARGB_8888);

??int width = emptyBmap.getWidth();
??int height = emptyBmap.getHeight();
??Bitmap charty = Bitmap.createBitmap(width, height,
????Bitmap.Config.ARGB_8888);

??charty = quicky_XY(emptyBmap);

??image.setImageBitmap(charty);
?}

?public static Bitmap quicky_XY(Bitmap bitmap) {
??// xode to get bitmap onto screen
??Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap
????.getHeight(), Config.ARGB_8888);
??Canvas canvas = new Canvas(output);

??final int color = 0xff0B0B61;
??final Paint paint = new Paint();
??final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
??final RectF rectF = new RectF(rect);
??final float roundPx = 12;

??// get the little rounded cornered outside
??paint.setAntiAlias(true);
??canvas.drawARGB(0, 0, 0, 0);
??paint.setColor(color);
??canvas.drawRoundRect(rectF, roundPx, roundPx, paint);

??// ---- NOw just draw on this bitmap

??// Set the labels info manually
??String[] cur_elt_array = new String[4];
??cur_elt_array[0] = "Voltage";
??cur_elt_array[1] = "volts";
??cur_elt_array[2] = "93"; // max
??cur_elt_array[3] = "0"; // min

??Vector labels = new Vector();
??labels.add(cur_elt_array);

??draw_the_grid(canvas, labels);

??// se the data to be plotted and we should on our way

??Vector data_2_plot = new Vector();

??data_2_plot.add("0.2");
??data_2_plot.add("1.2");
??data_2_plot.add("9.6");
??data_2_plot.add("83.2");
??data_2_plot.add("44.2");
??data_2_plot.add("20.2");
??data_2_plot.add("16.2");

??plot_array_list(canvas, data_2_plot, labels, "the title", 0);

??canvas.drawBitmap(bitmap, rect, rect, paint);

??return output;
?}

?public static void draw_the_grid(Canvas this_g, Vector these_labels) {
??double rounded_max = 0.0;
??double rounded_min = 0.0;
??double rounded_max_temp;
??Object curElt;
??String[] cur_elt_array;
??int left_margin_d, right_margin_d;

??cur_elt_array = (String[]) curElt;

??rounded_max = get_ceiling_or_floor(
????Double.parseDouble(cur_elt_array[2]), true);
??rounded_min = get_ceiling_or_floor(
????Double.parseDouble(cur_elt_array[3]), false);

??// ok so now we have the max value of the set just get a cool ceiling
??// and we go on
??final Paint paint = new Paint();
??paint.setTextSize(15);

??// with the mzrgins worked out draw the plotting grid
??paint.setStyle(Paint.Style.FILL);
??paint.setColor(Color.WHITE);

??// Android does by coords
??this_g
????.drawRect(drawSizes[0], drawSizes[1], drawSizes[0]
??????+ drawSizes[2], drawSizes[1] + drawSizes[3], paint);

??paint.setColor(Color.GRAY);

??// finally draw the grid

??paint.setStyle(Paint.Style.STROKE);
??this_g
????.drawRect(drawSizes[0], drawSizes[1], drawSizes[0]
??????+ drawSizes[2], drawSizes[1] + drawSizes[3], paint);

??// good for one value
??print_axis_values_4_grid(this_g, cur_elt_array[1], Double
????.toString(rounded_max), Double.toString(rounded_min),
????cur_elt_array[0], 2, 0);

?} // --- end of draw_grid ---

?private static Point scale_point(int this_x, double this_y,
???Point drawPoint, int scr_x, int scr_y, int scr_width,
???int src_height, double maxX, double minX, double maxY, double minY) {
??int temp_x, temp_y;
??Point temp = new Point();

??if (maxY == minY) // skip bad data
???return null;

??// don't touch it if is nothing
??try {
???temp_x = scr_x
?????+ (int) (((double) this_x - minX) * ((double) scr_width / (maxX - minX)));
???temp_y = scr_y
?????+ (int) ((maxY - this_y) * ((double) src_height / (maxY - minY)));

???temp.x = temp_x;
???temp.y = temp_y;
???drawPoint = temp;
??} catch (Exception e) {

???return (null);
??}

??return temp;

?} // --- end of scale_point --

?public static boolean plot_array_list(Canvas this_g,
???Vector this_array_list, Vector these_labels, String this_title,
???int only_this_idx) {
??int idx;
??int lRow;
??int nParms;
??int i, points_2_plot, shifted_idx;
??int prev_x, prev_y;
??int cur_x = 0, cur_y = 0;
??// Dim ShowMarker As Object
??Point cur_point = new Point();
??cur_point.set(0, 0);

??double cur_maxX, cur_minX, cur_maxY = 20, cur_minY = 0, cur_rangeY;
??int cur_start_x, cur_points_2_plot;

??int POINTS_TO_CHANGE = 30;
??double cur_OBD_val;

??// Object curElt;
??String curElt;
??String[] cur_elt_array;
??Object curElt2;
??String[] cur_elt_array2;

??final Paint paint = new Paint();

??try // catch in this block for some thing
??{
???points_2_plot = this_array_list.size();
???{
????cur_start_x = 0;
????cur_points_2_plot = points_2_plot;
????cur_maxX = cur_points_2_plot;
????cur_minX = 0;
???}

???// 'Create the plot points for this series from the ChartPoints
???// array:

???curElt = (String) this_array_list.elementAt(0);

???// the lines have to come out good
???paint.setStyle(Paint.Style.STROKE);
???//??????????????????
???// for( nParms = 0 ; nParms < cur_elt_array.length ; nParms++ )
???nParms = only_this_idx;
???{

????// get cur item labels
????curElt2 = these_labels.elementAt(nParms);
????cur_elt_array2 = (String[]) curElt2;

????cur_maxY = get_ceiling_or_floor(Double
??????.parseDouble(cur_elt_array2[2]), true);
????cur_minY = get_ceiling_or_floor(Double
??????.parseDouble(cur_elt_array2[3]), false);

????cur_points_2_plot = this_array_list.size();
????cur_maxX = cur_points_2_plot;

????curElt = (String) this_array_list.elementAt(0);
????cur_OBD_val = Double.parseDouble(curElt);

????cur_point = scale_point(0, cur_OBD_val, cur_point,
??????drawSizes[0], drawSizes[1], drawSizes[2], drawSizes[3],
??????cur_maxX, cur_minX, cur_maxY, cur_minY); // '(CInt(curAxisValues.Mins(nParms
????// - 2) / 5)
????// + 1) * 5)

????cur_x = cur_point.x;
????cur_y = cur_point.y;

????paint.setColor(Color.GREEN);

????// the point is only cool when samples are low
????if (cur_points_2_plot < POINTS_TO_CHANGE)
?????this_g.drawRect(cur_x - 2, cur_y - 2, cur_x - 2 + 4,
???????cur_y - 2 + 4, paint);

????prev_x = cur_x;
????prev_y = cur_y;

????// 'go and plot point for this parm -- pont after the 1st one
????for (lRow = cur_start_x + 1; lRow < cur_start_x
??????+ cur_points_2_plot - 1; lRow++) {
?????curElt = (String) this_array_list.elementAt(lRow);

?????cur_OBD_val = Double.parseDouble(curElt);

?????// 'work out an approx if cur Y values not avail(e.g.
?????// nothing)
?????// if (! (cur_elt_array[nParms ] == null ) ) //skip bad one
?????if (cur_OBD_val == Double.NaN)
??????continue; // skip bad one
?????{

??????cur_point = scale_point(lRow, cur_OBD_val, cur_point,
????????drawSizes[0], drawSizes[1], drawSizes[2],
????????drawSizes[3], cur_maxX, cur_minX, cur_maxY,
????????cur_minY);

??????cur_x = cur_point.x;
??????cur_y = cur_point.y;

??????if (cur_points_2_plot < POINTS_TO_CHANGE)
???????this_g.drawRect(cur_x - 2, cur_y - 2,
?????????cur_x - 2 + 4, cur_y - 2 + 4, paint);

??????this_g.drawLine(prev_x, prev_y, cur_x, cur_y, paint);
??????prev_x = cur_x;
??????prev_y = cur_y;

?????} // ' if end of this_array(lRow, nParms - 1)<> nothing

????} // end of for lrow

???} // end of for nParmns

???// this_g.invalidate();
???return (true);
??} catch (Exception e) {
???return (false);
??}

?} // --- end of plot_array_list --

?public static void print_axis_values_4_grid(Canvas thisDrawingArea,
???String cur_units, String cur_max, String cur_min, String cur_label,
???int x_guide, int this_idx) {
??String this_str;
??double delta = (Double.valueOf(cur_max).doubleValue() - Double.valueOf(
????cur_min).doubleValue()) / 5;

??final Paint paint = new Paint();
??paint.setColor(Color.WHITE);

??paint.setTypeface(Typeface.SANS_SERIF);
??paint.setTextSize(8);

??for (int i = 0; i < 6; i++) {
???this_str = Double
?????.toString((Double.valueOf(cur_min).doubleValue() + delta
???????* i));
???final int point = this_str.indexOf('.');
???if (point > 0) {
????// If has a decimal point, may need to clip off after or force 2
????// decimal places
????this_str = this_str + "00";
????this_str = this_str.substring(0, point + 3);
???} else {
????this_str = this_str + ".00";
???}

???if (i == 5) {
????thisDrawingArea.drawText(this_str, x_guide - 2, drawSizes[1]
??????+ drawSizes[3] - (i * drawSizes[3] / 5), paint);
???} else {
????thisDrawingArea.drawText(this_str, x_guide - 2, drawSizes[1]
??????+ drawSizes[3] - (i * drawSizes[3] / 5) - 3, paint);
???}

??}
??paint.setTextSize(10);

??switch (this_idx) {
??case 0:
???thisDrawingArea.drawText("? " + cur_label + " - " + cur_units,
?????x_guide - 2, drawSizes[1] - 15, paint);

???break;

??default:
???thisDrawingArea.drawText("? " + cur_label + " - " + cur_units,
?????x_guide - 2 - 30, drawSizes[1] - 15, paint);

???break;
??}

?private static int getCurTextLengthInPixels(Paint this_paint,
???String this_text) {
??FontMetrics fp = this_paint.getFontMetrics();
??Rect rect = new Rect();
??this_paint.getTextBounds(this_text, 0, this_text.length(), rect);
??return rect.width();
?}

?public static double get_ceiling_or_floor(double this_val, boolean is_max) {
??double this_min_tmp;
??int this_sign;
??int this_10_factor = 0;
??double this_rounded;

??if (this_val == 0.0) {
???this_rounded = 0.0;
???return this_rounded;
??}

??this_min_tmp = Math.abs(this_val);

??if (this_min_tmp >= 1.0 && this_min_tmp < 10.0)
???this_10_factor = 1;
??else if (this_min_tmp >= 10.0 && this_min_tmp < 100.0)
???this_10_factor = 10;
??else if (this_min_tmp >= 100.0 && this_min_tmp < 1000.0)
???this_10_factor = 100;
??else if (this_min_tmp >= 1000.0 && this_min_tmp < 10000.0)
???this_10_factor = 1000;
??else if (this_min_tmp >= 10000.0 && this_min_tmp < 100000.0)
???this_10_factor = 10000;

??// 'cover when min is pos and neg
??if (is_max) {
???if (this_val > 0.0)
????this_sign = 1;
???else
????this_sign = -1;

??} else {
???if (this_val > 0.0)
????this_sign = -1;
???else
????this_sign = 1;

??}

??if (this_min_tmp > 1)
???this_rounded = (double) (((int) (this_min_tmp / this_10_factor) + this_sign) * this_10_factor);
??else {
???this_rounded = (int) (this_min_tmp * 100.0);
???// ' cover same as above bfir number up to .001 less than tha it
???// will skip
???if (this_rounded >= 1 && this_rounded < 9)
????this_10_factor = 1;
???else if (this_rounded >= 10 && this_rounded < 99)
????this_10_factor = 10;
???else if (this_rounded >= 100 && this_rounded < 999)
????this_10_factor = 100;

???this_rounded = (double) (((int) ((this_rounded) / this_10_factor) + this_sign) * this_10_factor);
???this_rounded = (int) (this_rounded) / 100.0;

??}

??if (this_val < 0)
???this_rounded = -this_rounded;

??return this_rounded;

?}
}

源碼下載：http://files.cnblogs.com/salam/XYChart.rar

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