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8.需要在setPressure方法中设置重画方法

 

    //重画

    //invalidate();只能在主线程中调用

    //postInvalidate();可以在子线程中调用

    postInvalidate();

 

9.解决图形向下移动bug,取绝对值

new Thread(){

           public void run() {

              while (true) {

                  SystemClock.sleep(1000);

                  Random random = new Random();

                  int pressure= random.nextInt() % 210;

                  myPressureView.setPressure(Math.abs(pressure));

                 

              }

           };

       }.start();

 

 

 

10.锅炉爆炸后停止工作

new Thread(){

           public void run() {

              while (true) {

                  SystemClock.sleep(1000);

                  Random random = new Random();

                  int pressure= Math.abs(random.nextInt() % 210);

                  myPressureView.setPressure(pressure);

                  if(pressure >200){

                     break;

                  }

                 

              }

           };

       }.start();

 

 

 

1. 实现C语言端获取锅炉的压力值

  1.native代码

    /**

     * 从C端获取一个压力值

     * @return

     */

    public native int getPressure();

 

   {

      java.lang.System.loadLibrary("PressureDemo");

    }

 

 

   new Thread(){

           public void run() {

              while (true) {

                  SystemClock.sleep(1000);

//                Random random = new Random();

                  int pressure= getPressure();//Math.abs(random.nextInt() % 250);

                  myPressureView.setPressure(pressure);

                  if(pressure >200){

                     break;

                  }

                 

              }

           };

       }.start();

 

 

 

1. C代码

 

#include "com_atguigu_pressuredemo_MainActivity.h"

#include<stdio.h>

#include<stdlib.h>

 

/**模拟-得到锅炉的压力值

范围：0~250

*/

int getPressure()

{

   return rand()%250;

 

}

 

 

JNIEXPORT jint JNICALL Java_com_atguigu_pressuredemo_MainActivity_getPressure

  (JNIEnv *env, jobject obj){

 

    return getPressure();

}

 

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