Graph View
/*
Amarino - A prototyping software toolkit for Android and Arduino
Copyright (c) 2010 Bonifaz Kaufmann. All right reserved.
This application and its library is free software; you can redistribute
it and/or modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 3 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
import java.util.logging.Logger;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.View;
class GraphView extends Visualizer {
private static final String TAG = "GraphView";
private Bitmap mBitmap;
private Canvas mCanvas = new Canvas();
private float mSpeed = 1f;
private float mLastX;
private float[] mLastValue = new float[10]; // 10 should be more than enough
private int[] mColor = new int[4];
public GraphView(Context context) {
super(context);
init();
}
public GraphView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
private void init() {
mColor[0] = Color.argb(255, 100, 255, 100); // g
mColor[1] = Color.argb(255, 255, 255, 100); // y
mColor[2] = Color.argb(255, 255, 100, 100); // r
mColor[3] = Color.argb(255, 100, 255, 255); // c
mPaint.setFlags(Paint.ANTI_ALIAS_FLAG);
}
public void setData(float value) {
addDataPoint(value, mColor[0], mLastValue[0], 0);
invalidate();
}
public void setData(float[] values) {
final int length = values.length;
try {
for (int i = 0; i < length; i++) {
addDataPoint(values[i], mColor[i % 4], mLastValue[i], i);
}
} catch (ArrayIndexOutOfBoundsException e) {
/* mLastValue might run into this in extreme situations */
// but then we just do not want to support more than 10 values in
// our little graph
}
invalidate();
}
private void addDataPoint(float value, final int color,
final float lastValue, final int pos) {
value += minValue;
final Paint paint = mPaint;
float newX = mLastX + mSpeed;
final float v = mYOffset + value * mScaleY;
paint.setColor(color);
mCanvas.drawLine(mLastX, lastValue, newX, v, paint);
mLastValue[pos] = v;
if (pos == 0)
mLastX += mSpeed;
}
public void setSpeed(float speed) {
mSpeed = speed;
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
// TODO when screen size changes sometimes w or h == 0 -> Exception
mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.RGB_565);
mCanvas.setBitmap(mBitmap);
mCanvas.drawColor(0xFF111111);
mLastX = mWidth;
// set origin to zero
for (int i = 0; i < mLastValue.length; i++)
mLastValue[i] = minValue;
}
@Override
protected void onDraw(Canvas canvas) {
synchronized (this) {
if (mBitmap != null) {
final Paint paint = mPaint;
final Canvas cavas = mCanvas;
if (mLastX >= mWidth) {
mLastX = 0;
cavas.drawColor(0xFF111111);
int x = 20;
paint.setColor(0x33DDFFDD);
while (x < mWidth) {
cavas.drawLine(x, mYOffset, x, 0, paint);
x += 20;
}
final float v = mYOffset + minValue * mScaleY;
// draw the zero line
paint.setColor(0xFF779977);
cavas.drawLine(0, v, mWidth, v, paint);
}
paint.setColor(0xaa996666);
cavas.drawText(min, 1, mYOffset - 1, paint);
cavas.drawText(max, 1, textHeight - 1, paint);
canvas.drawBitmap(mBitmap, 0, 0, null);
}
}
}
}
abstract class Visualizer extends View {
Paint mPaint = new Paint();
float maxValue = 1024f;
float minValue = 0f;
float mScaleX;
float mScaleY;
float mYOffset;
float mWidth;
String min, max;
float textWidth = 0;
float textHeight = 0;
public Visualizer(Context context) {
super(context);
}
public Visualizer(Context context, AttributeSet attrs) {
super(context, attrs);
}
public abstract void setData(float value);
public abstract void setData(float[] values);
public void setBoundaries(float min, float max) {
this.min = String.valueOf(min);
this.max = String.valueOf(max);
minValue = -min;
maxValue = max - min;
mScaleY = -(mYOffset * (1.0f / maxValue));
mScaleX = (mWidth * (1.0f / maxValue));
float[] sizes = new float[this.max.length()];
textHeight = mPaint.getTextSize();
mPaint.getTextWidths(this.max, sizes);
for (float f : sizes)
textWidth += f;
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
mYOffset = h;
mWidth = w;
mScaleY = -(h * (1.0f / maxValue));
mScaleX = (w * (1.0f / maxValue));
super.onSizeChanged(w, h, oldw, oldh);
}
/* SIMPLE CAST FUNCTIONS */
public void setData(int value) {
setData((float) value);
}
public void setData(double value) {
setData((float) value);
}
public void setData(short value) {
setData((float) value);
}
public void setData(long value) {
setData((float) value);
}
public void setData(byte value) {
setData((float) value);
}
public void setData(boolean value) {
if (value)
setData(1f);
else
setData(0f);
}
public void setData(int[] values) {
final int length = values.length;
float[] arr = new float[length];
for (int i = 0; i < length; i++)
arr[i] = values[i];
setData(arr);
}
public void setData(double[] values) {
final int length = values.length;
float[] arr = new float[length];
for (int i = 0; i < length; i++)
arr[i] = (float) values[i];
setData(arr);
}
public void setData(short[] values) {
final int length = values.length;
float[] arr = new float[length];
for (int i = 0; i < length; i++)
arr[i] = values[i];
setData(arr);
}
public void setData(long[] values) {
final int length = values.length;
float[] arr = new float[length];
for (int i = 0; i < length; i++)
arr[i] = values[i];
setData(arr);
}
public void setData(byte[] values) {
final int length = values.length;
float[] arr = new float[length];
for (int i = 0; i < length; i++)
arr[i] = values[i];
setData(arr);
}
public void setData(boolean[] values) {
final int length = values.length;
float[] arr = new float[length];
for (int i = 0; i < length; i++)
arr[i] = values[i] ? 1 : 0;
setData(arr);
}
public void setData(String[] values) {
final int length = values.length;
float[] arr = new float[length];
for (int i = 0; i < length; i++)
arr[i] = Float.valueOf(values[i]);
setData(arr);
}
}
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