单击按钮如何调用另一个活动？

Question

所以我正在尝试创建一个 android 应用程序来显示一些简单的电池信息。现在我想获取该信息并在应用程序内绘制图表。我有以下代码：

public class MainActivity extends ActionBarActivity {
private TextView level,voltage, status1,temp,health1,tech,sour,amp;
Thread myThread;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        level=(TextView)findViewById(R.id.level);
        voltage=(TextView)findViewById(R.id.volt);
        status1=(TextView)findViewById(R.id.stat);
        temp=(TextView)findViewById(R.id.temp);
        health1=(TextView)findViewById(R.id.healt);
        tech=(TextView)findViewById(R.id.tech);
        sour=(TextView)findViewById(R.id.source);
        Button b = (Button) findViewById(R.id.ex);
        Button g = (Button) findViewById(R.id.graphButton);
        amp=(TextView)findViewById(R.id.current);
        b.setOnClickListener(new View.OnClickListener(){
             public void onClick(View v) {
                    // TODO Auto-generated method stub
                    finish();
                  }
        });

        g.setOnClickListener(new View.OnClickListener(){
             public void onClick(View v) {

       //how can i jump to DynamicGraphActivity

             }
        });

        this.registerReceiver(this.myBatteryReceiver,
                 new IntentFilter(Intent.ACTION_BATTERY_CHANGED));


    }

    private BroadcastReceiver myBatteryReceiver
       = new BroadcastReceiver(){

     @SuppressLint("InlinedApi")
    @Override
     public void onReceive(Context arg0, Intent arg1) {
      // TODO Auto-generated method stub

      if (arg1.getAction().equals(Intent.ACTION_BATTERY_CHANGED)){

          int lv = arg1.getIntExtra("level", 0);
       level.setText("Level: "
         + String.valueOf(lv) + "%");

       voltage.setText("Voltage: "
                 + String.valueOf((float)arg1.getIntExtra("voltage", 0)/1000) + "V");
               temp.setText("Temperature: "
                 + String.valueOf((float)arg1.getIntExtra("temperature", 0)/10) + "c");
               tech.setText("Technology: " + arg1.getStringExtra("technology"));

               int status = arg1.getIntExtra("status", BatteryManager.BATTERY_STATUS_UNKNOWN);
               String strStatus;
               if (status == BatteryManager.BATTERY_STATUS_CHARGING){
                strStatus = "Charging";
               } else if (status == BatteryManager.BATTERY_STATUS_DISCHARGING){
                strStatus = "Dis-charging";
               } else if (status == BatteryManager.BATTERY_STATUS_NOT_CHARGING){
                strStatus = "Not charging";
               } else if (status == BatteryManager.BATTERY_STATUS_FULL){
                strStatus = "Full";
               } else {
                strStatus = "Unknown";
               }
               status1.setText("Status: " + strStatus);

               //int source=arg1.getIntExtra("source", BatteryManager.BATTERY_STATUS_UNKNOWN);
               if(Build.VERSION.SDK_INT >= 21){
             BatteryManager battery = (BatteryManager)getSystemService(Context.BATTERY_SERVICE);
             int current=battery.getIntProperty(BatteryManager.BATTERY_PROPERTY_CURRENT_NOW);
             int currentAvg=battery.getIntProperty(BatteryManager.BATTERY_PROPERTY_CURRENT_AVERAGE);
             int energy=battery.getIntProperty(BatteryManager.BATTERY_PROPERTY_ENERGY_COUNTER);
             int capacity=battery.getIntProperty(BatteryManager.BATTERY_PROPERTY_CHARGE_COUNTER);
             int bCapacity=battery.getIntProperty(BatteryManager.BATTERY_PROPERTY_CAPACITY);
             String string1 = "Current: "+ current*1000+" uA"+"\n";
             string1+="Average Current: "+currentAvg+" uA"+"\n";
             string1+="Remaining energy: "+energy+" nWh"+"\n";
             string1+="Capacity: "+capacity+" uAh"+"\n\n";

             amp.setText(string1);
               }


               int health = arg1.getIntExtra("health", BatteryManager.BATTERY_HEALTH_UNKNOWN);
               String strHealth;
               if (health == BatteryManager.BATTERY_HEALTH_GOOD){
                strHealth = "Good";
               } else if (health == BatteryManager.BATTERY_HEALTH_OVERHEAT){
                strHealth = "Over Heat";
               } else if (health == BatteryManager.BATTERY_HEALTH_DEAD){
                strHealth = "Dead";
               } else if (health == BatteryManager.BATTERY_HEALTH_OVER_VOLTAGE){
                strHealth = "Over Voltage";
               } else if (health == BatteryManager.BATTERY_HEALTH_UNSPECIFIED_FAILURE){
                strHealth = "Unspecified Failure";
               } else{
                strHealth = "Unknown";
               }
               health1.setText("Health: " + strHealth);

              }
             }

               };



    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.

        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}

2nd Activity 或 DynamicGraphActivity：

public class DynamicGraphActivity extends Activity {

    private static GraphicalView view;
    private LineGraph line = new LineGraph();
    private static Thread thread;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        thread = new Thread() {
            public void run()
            {
                for (int i = 0; i < 15; i++) 
                {
                    try {
                        Thread.sleep(2000);
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                    Point p = MockData.getDataFromReceiver(i); // We got new data!
                    line.addNewPoints(p); // Add it to our graph
                    view.repaint();
                }
            }
        };
        thread.start();
    }

    @Override
    protected void onStart() {
        super.onStart();
        view = line.getView(this);
        setContentView(view);
    }

}

import org.achartengine.ChartFactory;
import org.achartengine.GraphicalView;
import org.achartengine.chart.PointStyle;
import org.achartengine.model.TimeSeries;
import org.achartengine.model.XYMultipleSeriesDataset;
import org.achartengine.renderer.XYMultipleSeriesRenderer;
import org.achartengine.renderer.XYSeriesRenderer;

import android.content.Context;
import android.graphics.Color;

public class LineGraph {

    private GraphicalView view;

    private TimeSeries dataset = new TimeSeries("Rain Fall"); 
    private XYMultipleSeriesDataset mDataset = new XYMultipleSeriesDataset();

    private XYSeriesRenderer renderer = new XYSeriesRenderer(); // This will be used to customize line 1
    private XYMultipleSeriesRenderer mRenderer = new XYMultipleSeriesRenderer(); // Holds a collection of XYSeriesRenderer and customizes the graph

    public LineGraph()
    {
        // Add single dataset to multiple dataset
        mDataset.addSeries(dataset);

        // Customization time for line 1!
        renderer.setColor(Color.WHITE);
        renderer.setPointStyle(PointStyle.SQUARE);
        renderer.setFillPoints(true);

        // Enable Zoom
        mRenderer.setZoomButtonsVisible(true);
        mRenderer.setXTitle("Day #");
        mRenderer.setYTitle("CM in Rainfall");

        // Add single renderer to multiple renderer
        mRenderer.addSeriesRenderer(renderer);  
    }

    public GraphicalView getView(Context context) 
    {
        view =  ChartFactory.getLineChartView(context, mDataset, mRenderer);
        return view;
    }

    public void addNewPoints(Point p)
    {
        dataset.add(p.getX(), p.getY());
    }

}

import java.util.Random;

public class MockData {

    // x is the day number, 0, 1, 2, 3
    public static Point getDataFromReceiver(int x)
    {
        return new Point(x, generateRandomData());
    }

    private static int generateRandomData()
    {
        Random random = new Random();
        return random.nextInt(40);
    }
}

public class Point {

    private int x;
    private int y;

    public Point( int x, int y)
    {
        this.x = x;
        this.y = y;
    }

    public int getX() {
        return x;
    }

    public int getY() {
        return y;
    }

}

现在在按钮 g 内，我想调用 DynamicGraphActivity 类，以便它调用该类并使用一些随机值绘制图形。但它不工作。当我点击按钮时，它什么也没做。我该如何解决这个问题？

我的另一个问题是，如何使用这些代码随时间绘制电池信息，例如电压、充电或放电/ 任何帮助将不胜感激。 谢谢你

Answer 1

嗯，任何课程或活动之间都有区别。 Activity 有一个可视化的布局映射。查看此link 了解更多信息。

在您的 g 按钮单击侦听器中添加此代码。

g.setOnClickListener(new View.OnClickListener(){
         public void onClick(View v) {
    Intent intent = new Intent(MainActivity.this, DynamicGraphActivity.class);
    startActivity(intent);
      }
    });

您还需要在 AndroidManifest.xml 以及应用程序标记下添加其他活动。（如果您创建新应用程序，则应用程序标记内已经有活动标记。但是对于较新的活动，您不需要任何意图过滤器)

<activity
    android:name=".DynamicGraphActivity"
 />

我注意到您对两个活动都使用相同的布局（main.xml）的另一件事。 在 layouts 文件夹中创建另一个布局并将其映射到 DynamicGraphActivity。 假设您创建了 second.xml。 所以你的 DynamicGraphActivity oncreate() 有：

setContentView(R.layout.second);

Answer 2

Intent 2ndActivity = new Intent(this, blabla.class);
startActivity(2ndActivity);

对于按钮和额外价值，您可以使用 Bundle、Parcel 或只使用 putExtra。

关于电池信息，请从谷歌开发者处阅读

Answer 3

在您的按钮中单击输入此代码

Intent intent = new Intent(MainActivity.this, DynamicGraphActivity.class);
startActivity(intent);

并在您的 AndroidManifest.xml 中定义此活动

<activity
        android:name=".DynamicGraphActivity"
        android:theme="@android:style/Theme.Translucent.NoTitleBar" />

有关电池信息，您可以参考此链接... http://developer.android.com/reference/android/os/BatteryManager.html http://mobiledevtuts.com/android/android-sdk-get-device-battery-information/ Get battery level and state in Android