我的代码在下面。
我真正不了解的是如何使用按钮来更改我正在绘制的图形。我有点希望能够调用类似于重绘图形的方法，但我看不出我会怎么做。
干杯
菲尔
package com.android.phil.smartphonecharts;
import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.os.Bundle;
import android.view.Display;
import android.view.View;
import android.widget.ImageButton;
import android.widget.RelativeLayout;
public class GraphActivity extends Activity
{
int[][] graphData = {{591566,601708,591566,600509},
{593573,594182,586592,591489},
{600088,602233,596358,599401},
{592071,601150,592071,600120},
{592292,593668,586095,591998},
{599672,599672,591552,592353},
{601442,602856,592655,599676},
{606747,610577,601314,601480},
{609190,609678,604883,608299},
{609659,610142,606671,608738},
{604655,609576,604238,608527},
{605158,607207,602377,603708},
{607479,609148,604210,606009},
{600472,607140,597344,606290},
{603668,604520,598648,602001},
{606743,608430,604950,605229},
{604232,609133,603288,609133},
{600916,605409,599716,605103},
{600264,602341,598683,599738},
{598570,599359,595182,598334},
{597654,602046,597271,600007},
{592071,601150,592071,600120},
};
int highest = 0;
int lowest = 0;
int multiY = 10;
int multiX = 21;
int graphToggle = 0;
int numbPeriods = 22;
float previous = 0;
float current = 0;
float stepX = 0;
float stepY = 0;
float stepPercent = 0;
float topLeftX = 0;
float topLeftY = 0;
float bottomRightX = 0;
float bottomRightY = 0;
float graphHeight = 0;
float graphWidth = 0;
double graphLow = 0;
double graphHigh = 0;
double graphRange = 0;
double n = 0;
double m = 0;
public int graph_toggle = 0;
public int data_toggle=0;
public float width;
public float height;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.graph_layout);
Display display = getWindowManager().getDefaultDisplay();
width = display.getWidth();
height = display.getHeight();
final ImageButton graph_toggle_button = (ImageButton) findViewById(R.id.graph_toggle);
final ImageButton graph_settings_button = (ImageButton) findViewById(R.id.graph_type);
final ImageButton data_toggle_button = (ImageButton) findViewById(R.id.data_toggle);
final ImageButton moving_averages_button = (ImageButton)findViewById(R.id.moving_averages);
//Define the view into which our canvas will be drawn.
int graph_display_height = (int)(height*0.75);
int graph_display_width = (int)width;
CustomDrawableView mCustomDrawableView = new CustomDrawableView(this);
RelativeLayout graphLayout = (RelativeLayout)findViewById(R.id.graph_window);
RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(graph_display_width,graph_display_height);
lp.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
mCustomDrawableView.setLayoutParams(lp);
graphLayout.addView(mCustomDrawableView);
graph_toggle_button.setOnClickListener(new View.OnClickListener()
{
public void onClick(View arg0)
{
if (graph_toggle==2)
{
graph_toggle=0;
}
else
{
graph_toggle++;
}
if (graph_toggle==0)
{
graph_settings_button.setImageResource(R.drawable.close);
}
if (graph_toggle==1)
{
graph_settings_button.setImageResource(R.drawable.ohlc_bars);
}
if(graph_toggle==2)
{
graph_settings_button.setImageResource(R.drawable.candles);
}
}
});
data_toggle_button.setOnClickListener(new View.OnClickListener()
{
public void onClick(View arg0)
{
if (data_toggle==2)
{
data_toggle=0;
}
else
{
data_toggle++;
}
if (data_toggle==0)
{
data_toggle_button.setImageResource(R.drawable.ohlc_bars_daily);
}
if (data_toggle==1)
{
data_toggle_button.setImageResource(R.drawable.ohlc_bars_weekly);
}
if(data_toggle==2)
{
data_toggle_button.setImageResource(R.drawable.ohlc_bars_monthly);
}
}
});
}
public class CustomDrawableView extends View
{
public CustomDrawableView(Context context)
{
super(context);
}
@Override
protected void onDraw(Canvas canvas)
{
invalidate();
super.onDraw(canvas);
// custom drawing code here
// remember: y increases from top to bottom
// x increases from left to right
Paint paint = new Paint();
paint.setStyle(Paint.Style.FILL);
// make the entire canvas white
paint.setColor(Color.TRANSPARENT);
canvas.drawPaint(paint);
//Set co-ordinates of display window using half the heigh of the screen and
//indent the window by 5%
topLeftX = (float)0;
topLeftY = (float)(height*0.01);
bottomRightX = (float)(width*0.80);
bottomRightY = (float)(height*0.45);
//Width and height of the window are defined by the X and Y co-ords calculated above.
graphWidth = bottomRightX-topLeftX;
graphHeight = bottomRightY-topLeftY;
//Calculate the HighestHigh and LowestLow of the data set.
highest = mHighestHigh(graphData,graphToggle);
lowest = mLowestLow(graphData,graphToggle);
//Total graph range that we want to display based on the values in data
//Calculate the Lowest value from the data set drawn on the graph
graphLow = lowest*0.99;
//Calculate the highest value from the data set drawn on the graph
graphHigh = highest*1.01;
//is equal to the highest value minus lowest value +/-5%
graphRange = graphHigh-graphLow;
//stepX = space between vertical bars
stepX = graphWidth/multiX;
//stepY = space between horizontal bars
stepY = graphHeight/multiY;
//step = 1 hundredth of the total height of the box.
stepPercent = (graphHeight)/100;
//draw the outline box
paint.setStyle(Style.STROKE);
paint.setColor(Color.WHITE);
canvas.drawRect(topLeftX, topLeftY, bottomRightX, bottomRightY, paint);
//draw horizontal lines
paint.setColor(Color.WHITE);
paint.setTextSize(10);
canvas.drawText(mD2S2DP(graphLow/100), (float)(width*0.81), bottomRightY+5, paint);
for (int i = 1; i < multiY; i++)
{//canvas.drawLine(startX, startY, stopX, stopY, paint)
paint.setColor(Color.rgb(255,0,0));
canvas.drawLine(topLeftX, topLeftY+(stepY*i), bottomRightX, topLeftY+(stepY*i), paint);
paint.setColor(Color.WHITE);
paint.setTextSize(10);
canvas.drawText("Hello Android!", (float)(width*0.81), topLeftY+(stepY*i)+5,paint);
}
paint.setColor(Color.WHITE);
paint.setTextSize(10);
canvas.drawText(mD2S2DP(graphHigh/100), (float)(width*0.81), topLeftY+5, paint);
//draw vertical lines and diagonal random price lines
for (int i = 1; i < multiX; i++)
{//canvas.drawLine(startX, startY, stopX, stopY, paint)
paint.setColor(Color.rgb(255,255,255));
paint.setStrokeWidth(1);
canvas.drawLine(topLeftX+(stepX*i), topLeftY, topLeftX+(stepX*i), bottomRightY, paint);
}
//Inverts the data set and draws it at the appropriate
n = (topLeftY-bottomRightY)/graphRange;
m = bottomRightY-(n*graphLow);
//draw close line graph
for (int i = 1; i < (multiX+1); i++)
{
//DashPathEffect dashPath = new DashPathEffect(new float[]{10,10}, 1);
//paint.setPathEffect(dashPath);
previous = (float)(n*graphData[i-1][3]+m);
current = (float)(n*graphData[i][3]+m);
if(previous>current)
{
paint.setColor(Color.rgb(255,0,0));
paint.setStrokeWidth(2);
}
else
{
paint.setColor(Color.rgb(0,255,0));
paint.setStrokeWidth(2);
}
//canvas.drawLine(startX, startY, stopX, stopY, paint)
canvas.drawLine(topLeftX+(stepX*(i-1)),previous, topLeftX+(stepX*i), current, paint);
}
}
}
public int mHighestHigh(int[][]data, int graphToggle)
{//method to calculate the highest high of the data set;
int highValue = graphToggle==0?data[0][3]:data[0][1];
for (int i=1; i<data.length; i++)
{
if ((graphToggle==0?data[i][3]:data[i][1]) > highValue)
{
highValue = graphToggle==0?data[i][3]:data[i][1]; //new maximum
}
}
System.out.println("highValue="+highValue);
return highValue;
}
public int mLowestLow(int[][]data,int graphToggle)
{//method to calculate the lowest low of the data set;
int lowValue = graphToggle==0?data[0][3]:data[0][2];
for (int i=1; i<data.length; i++)
{
if ((graphToggle==0?data[i][3]:data[i][2]) < lowValue)
{
lowValue = graphToggle==0?data[i][3]:data[i][2]; //new minimum
}
}
System.out.println("lowValue=:"+lowValue);
return lowValue;
}
public String mD2S2DP(double doubleValue)
{//method to turn a double to a string and return it to two dp
//Convert the double to a string.
String tempString = Double.toString(doubleValue);
//Find the location of the decimal point in the string.
int index = tempString.indexOf('.');
//remove anything from the string after 2 characters after the decimal point.
String returnString = tempString.substring(0, index+3);
//return the result.
return returnString;
}
}
答案 0 :(得分：2)
该方法是invalidate()，它在主线程循环中安排重新绘制您调用它的视图。实际上，您不应该在自定义视图onDraw()中调用它（除非您需要重复重绘，以执行一些类似帧的动画）。
通常查看更改影响方面的内容的方法（如ImageView.setImageDrawable()）也可以调用invalidate()。因此，您可以添加执行更改的CustomDrawableView.setGraphData(data)方法，然后调用invalidate()。
当然，您也可以从按钮单击侦听器代码中调用mCustomDrawableView.invalidate()。
请注意，如果更改还涉及视图父级的大小或位置，您还可以调用requestLayout()。