首先我应该说这是我制作的第一个Android应用程序，它的方式远远超出我的经验......所以手头有这个：
我有一个应用程序，在Android 4.1上用作汽车车速表。它从arduino，通过usb连接获取一些信息（逗号解析的字符串），并以一种奇特的方式显示它。一般来说，应用程序工作正常。一切都正确显示，应该显示在哪里。
问题出现了，当我出于某些原因退出，并重新启动应用程序...如果我这样做，所有应该＆＃34;始终显示的信息＆＃34;像KM / hr，燃料，转速，没有在全部显示。但其他信息，如转向灯或各种汽车信号，都完美展示......（这意味着应用程序成功获取并翻译了USB中的序列号。）任何想法，我做错了什么，或者如何解决这个问题??
负责图形的代码在这里：
public void onCreate(Bundle savedInstanceState) {
super.onCreate(null);
setContentView(new MyView(this));
.
.
}
public class MyView extends View {
public MyView(Context context) {
super(context);
}
@Override
protected void onDraw(Canvas canvas) {
try{
super.onDraw(canvas);
paint.setStyle(Paint.Style.FILL);
//BACKGROUD/// //ALWAYS SHOWN
canvas.drawBitmap(Backgroundbmp,0, 0, null);
//WARNINGS// //ALWAYS SHOWN
if (HighBeam==0){
canvas.drawBitmap(High_Beam,300,490, null);
}
if (EngineCheck==0){
canvas.drawBitmap(Engine_Check,570, 490, null);
}
if (CoolantLevel==0){
canvas.drawBitmap(coolant_Level,400, 490, null);
}
if (Oil==0){
canvas.drawBitmap(Oil_pressure,670, 490, null);
}
//FLASH//
if (Rflash==0){
canvas.drawBitmap(Lflash_icon,250,80,null);
}
if (Lflash==0){
canvas.drawBitmap(Rflash_icon,697,80,null);
}
//DATE-TIME// //ALWAYS SHOWN
Calendar c = Calendar.getInstance();
String formattedDate = df.format(c.getTime());
paint.setColor(Color.parseColor("#FFFFFF"));
paint.setTextSize (100) ;
canvas.drawText(formattedDate,900,70,paint);
// ODOMETER - - TRIP ; //NOT SHOWN IN SECOND START
paint.setTextSize (30) ;
canvas.drawText(Odometer,510,390,paint);
canvas.drawText(TripA,930,164,paint);
canvas.drawText(TripB,930,216,paint);
//MPG //
canvas.drawText(currentMPG+" Lt/h",160,160,paint);
canvas.drawText(overallMPG+" Lt/h",140,205,paint);
//FUEL-TEMP//
paint.setTextSize (35) ;
canvas.drawText(FUEL+" Lt",745,450,paint);
canvas.drawText(TEMP+" °C",285,450,paint);
// SPEED //
paint.setColor(Color.parseColor("#56BAEA"));
paint.setTextSize (220) ;
String speed = Integer.toString(rawSPEED);
canvas.drawText(speed,520,270,paint);
paint.setStyle(Paint.Style.STROKE);
// RPM ////
paint.setStrokeWidth(35);
paint.setColor(Color.parseColor("#25DBFF"));
int angle = (int) (0.0225*rawRPM) ;
//1
oval.set(305,63, 725,482); //(left ,top, right, bot )
canvas.drawArc(oval,90, angle, false, paint);
//2
paint.setColor(Color.parseColor("#89ECFF"));
paint.setStrokeWidth(20);
oval.set(300,58, 725,487);
canvas.drawArc(oval,90, angle, false, paint);
if (rawRPM>=4500){
//1
paint.setColor(Color.parseColor("#22FF2A"));
paint.setStrokeWidth(35);
oval.set(305,63, 725,482); //(left ,top, right, bot )
canvas.drawArc(oval,191, angle-101, false, paint);
//2
paint.setColor(Color.parseColor("#5CFF62"));
paint.setStrokeWidth(20);
oval.set(300,58, 725,487);
canvas.drawArc(oval,191, angle-101, false, paint);
}
if (rawRPM>6000){
//1
paint.setColor(Color.parseColor("#FF0000"));
paint.setStrokeWidth(35);
oval.set(305,63, 725,482); //(left ,top, right, bot )
canvas.drawArc(oval,230, angle-140, false, paint);
//2
paint.setColor(Color.parseColor("#FF2525"));
paint.setStrokeWidth(20);
oval.set(300,58, 725,487);
canvas.drawArc(oval,230, angle-140, false, paint);
}
//3
paint.setColor(Color.parseColor("#FFFFFF"));
paint.setStrokeWidth(2);
oval.set(291,50, 738,496);
canvas.drawArc(oval,90, angle, false, paint);
// FUEL//
int tempFUEL=FuelBar;
//1
paint.setStrokeWidth(3);
if (rawFUEL>=30.0){
tempFUEL = FuelBar -30 ;
float ignore =(float)(-0.116*tempFUEL+ 7) ;
paint.setColor(Color.parseColor("#3782F2"));
float[] fa= {835,423,830,522 ,840,425,835,522 ,845,427,840,522 ,850,429,845,522 ,855,431,850,522 ,860,434,855,522 ,865,436,860,522}; // left,right +5 top = +2
canvas.drawLines(fa,4*(int)ignore,28-4*(int)ignore,paint) ; //(left ,top, right, bot )
tempFUEL=30;
}
//2
float ignore =(float)(-0.83*tempFUEL+25) ;
paint.setColor(Color.parseColor("#8EFFFF"));
float[] fb= {870,438,865,522 ,875,440,870,522 ,880,442,875,522 ,885,444,880,522 ,890,446,885,522 ,895,449,890,522 ,900,451,895,522 ,905,454,900,522 ,910,456,905,522 ,915,459,910,522 ,920,461,915,522 ,925,463,920,522 ,930,466,925,522 ,935,469,930,522 ,940,471,935,522 ,945,473,940,522 ,950,475,945,522 ,955,478,950,522 ,960,480,955,522 ,965,482,960,522 ,970,485,965,522 ,975,487,970,522 ,980,489,975,522 ,985,492,980,522 ,990,494,985,522 ,}; // left,right +5 top = +2
canvas.drawLines(fb,4*(int)ignore,fb.length-4*(int)ignore ,paint) ; //(left ,top, right, bot )
//3
paint.setStrokeWidth(2);
paint.setColor(Color.parseColor("#000000"));
canvas.drawLine(833,422,992,494,paint);
paint.setStrokeWidth(3);
//TEMP///
int tempTEMP = rawTEMP;
paint.setStrokeWidth(3);
//1
if (rawTEMP>=90){
tempTEMP= tempTEMP-90;
ignore = (float)(-0.12*(float)tempTEMP +6);
paint.setColor(Color.parseColor("#3782F2"));
float[] Tb= {187,424,192,522, 182,426,187,522, 177,428,182,522, 172,430,177,522, 167,432,172,522, 162,434,167,522, }; // left,right +5 top = +2
canvas.drawLines(Tb,4*(int)ignore,Tb.length - 4*(int)ignore,paint) ; //(left ,top, right, bot )
tempTEMP=90;
}
//2
ignore= (float)(-0.288*(float)tempTEMP +26);
paint.setColor(Color.parseColor("#8EFFFF"));
float[] Ta= {157,436,162,522, 152,438,157,522, 147,440,152,522, 142,442,147,522, 137,444,142,522, 132,446,137,522, 127,448,132,522, 122,451,127,522, 117,453,122,522, 112,455,117,522, 107,457,112,522, 102,460,107,522, 97,461,102,522, 92,462,97,522, 87,465,92,522, 82,470,87,522, 77,472,82,522, 72,474,77,522, 67,476,72,522, 62,479,67,522, 57,481,62,522, 52,483,57,522, 47,485,52,522, 42,487,47,522, 37,489,42,522 , 32,491,37,522 }; // left,right +5 top = +2
canvas.drawLines(Ta,4*(int)ignore,Ta.length - 4*(int)ignore,paint) ; //(left ,top, right, bot )
//3
paint.setColor(Color.parseColor("#000000"));
paint.setStrokeWidth(2);
canvas.drawLine(30,492,189,420,paint);
}catch (Exception e) { }
invalidate();
}
答案 0 :(得分：0)
尝试从onResume调用onDraw？
答案 1 :(得分：0)
感谢你的帮助！我解决了我的问题，毕竟，它与正确的onResume和onDestroy（）无关...正如我所提到的，在第二次启动之后，一些图形仍在显示...在我的代码中，它是图形高于“里程表”draw.text ..原因是，里程表值是从文本文件中获取的，在第一次关闭后可能会损坏...我删除了该行，并且现在该程序按预期工作！