Question

我想利用选项卡式活动在加速度计数据选项卡和日志选项卡之间滚动。我有一个java片段，它膨胀加速度计布局，并调用加速度计类来显示布局信息。

这两项活动似乎同时开始，因为应用程序以加速度计活动开始，当按下后退按钮时，它会转到选项卡式活动。这是我的清单中的问题吗？（包括大多数项目文件）

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="nrtj.sleeptracker" >

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name=".MainActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

    <activity android:name=".AccelerometerActivity"
        android:label="@string/app_name">
        <intent-filter>
            <action android:name="android.intent.action.VIEW"/>
        </intent-filter>
    </activity>
</application>

</manifest>

这是要求加速计布局和活动的片段：

public class AccelerometerFragment extends Fragment {

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.activity_accelerometer, container, false);
    return rootView;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    Intent intent = new Intent(getActivity(), AccelerometerActivity.class);
    startActivity(intent);
}
}

这是加速度计布局：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >

<TextView
    android:id="@+id/x_axis_Text"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:ems="10"
    android:inputType="none"
    android:paddingLeft="50dp"
    android:textColor="#0000FF"
    android:background="#FFFFFF"
    android:text="@string/x_axis_title"
    android:textSize="@android:dimen/notification_large_icon_height" />

<TextView
    android:id="@+id/y_axis_Text"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:ems="10"
    android:inputType="none"
    android:paddingLeft="50dp"
    android:textColor="#008800"
    android:background="#FFFFFF"
    android:text="@string/y_axis_title"
    android:textSize="@android:dimen/notification_large_icon_height" />

<TextView
    android:id="@+id/z_axis_Text"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:ems="10"
    android:inputType="none"
    android:paddingLeft="50dp"
    android:textColor="#FF0000"
    android:background="#FFFFFF"
    android:text="@string/z_axis_title"
    android:textSize="@android:dimen/notification_large_icon_height" />

<com.androidplot.xy.XYPlot
    android:id="@+id/dynamicPlot"
    android:layout_width="fill_parent"
    android:layout_height="0dp"
    android:layout_marginLeft="10dp"
    android:layout_marginRight="10dp"
    android:layout_marginTop="10dp"
    android:background="#FFFFFF"
    android:layout_weight="0.62"
    title="@string/dynamic_plot" />

</LinearLayout>

这是加速度计活动（它从Pebble Watch获取数据）：

public class AccelerometerActivity extends Activity {

private static final String TAG = "SleepTracker";

// The tuple key corresponding to a vector received from the watch
private static final int PP_KEY_CMD = 128;
private static final int PP_KEY_X   = 1;
private static final int PP_KEY_Y   = 2;
private static final int PP_KEY_Z   = 3;

@SuppressWarnings("unused")
private static final int PP_CMD_INVALID = 0;
private static final int PP_CMD_VECTOR  = 1;

public static final int VECTOR_INDEX_X  = 0;
public static final int VECTOR_INDEX_Y  = 1;
public static final int VECTOR_INDEX_Z  = 2;

private static int vector[] = new int[3];

private PebbleKit.PebbleDataReceiver dataReceiver;

// This UUID identifies the SleepTracker app.
private static final UUID SLEEPTRACKER_UUID = UUID.fromString("273761eb-97dc-4f08-b353-3384a2170902");

private static final int SAMPLE_SIZE = 30;

private XYPlot xyPlot = null;

SimpleXYSeries xSeries = null;
SimpleXYSeries ySeries = null;
SimpleXYSeries zSeries = null;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    Log.i(TAG, "onCreate: ");

    setContentView(R.layout.activity_accelerometer);

    vector[VECTOR_INDEX_X] = 0;
    vector[VECTOR_INDEX_Y] = 0;
    vector[VECTOR_INDEX_Z] = 0;

    PebbleKit.startAppOnPebble(getApplicationContext(), SLEEPTRACKER_UUID);


    xyPlot = (XYPlot) findViewById(R.id.dynamicPlot);


    xyPlot.getGraphWidget().getBackgroundPaint().setColor(Color.WHITE);
    xyPlot.getGraphWidget().getGridBackgroundPaint().setColor(Color.WHITE);

    xyPlot.getGraphWidget().setDomainValueFormat(new DecimalFormat("0.0"));
    xyPlot.getGraphWidget().setRangeValueFormat(new DecimalFormat("0"));

    xyPlot.getGraphWidget().getDomainLabelPaint().setColor(Color.BLACK);
    xyPlot.getGraphWidget().getRangeLabelPaint().setColor(Color.BLACK);

    xyPlot.getGraphWidget().getDomainOriginLabelPaint().setColor(Color.BLACK);
    xyPlot.getGraphWidget().getDomainOriginLinePaint().setColor(Color.BLACK);
    xyPlot.getGraphWidget().getRangeOriginLinePaint().setColor(Color.BLACK);

    xyPlot.setTicksPerDomainLabel(1);
    xyPlot.setTicksPerRangeLabel(1);

    xyPlot.getGraphWidget().getDomainLabelPaint().setTextSize(30);
    xyPlot.getGraphWidget().getRangeLabelPaint().setTextSize(30);

    xyPlot.getGraphWidget().setDomainLabelWidth(40);
    xyPlot.getGraphWidget().setRangeLabelWidth(80);

    xyPlot.setDomainLabel("time");
    xyPlot.getDomainLabelWidget().pack();

    xyPlot.setRangeLabel("G-force");
    xyPlot.getRangeLabelWidget().pack();

    xyPlot.setRangeBoundaries(-1024, 1024, BoundaryMode.FIXED);
    xyPlot.setDomainBoundaries(0, SAMPLE_SIZE, BoundaryMode.FIXED);


    xSeries = new SimpleXYSeries("X-axis");
    xSeries.useImplicitXVals();

    ySeries = new SimpleXYSeries("Y-axis");
    ySeries.useImplicitXVals();

    zSeries = new SimpleXYSeries("Z-axis");
    zSeries.useImplicitXVals();

    // Blue line for X axis.
    LineAndPointFormatter fmtX = new LineAndPointFormatter(Color.BLUE, null, null, null);
    xyPlot.addSeries(xSeries, fmtX);

    // Green line for Y axis.
    LineAndPointFormatter fmtY = new LineAndPointFormatter(Color.GREEN, null, null, null);
    xyPlot.addSeries(ySeries, fmtY);

    // Red line for Z axis.
    LineAndPointFormatter fmtZ = new LineAndPointFormatter(Color.RED, null, null, null);
    xyPlot.addSeries(zSeries, fmtZ);
}

@Override
public void onPause() {
    super.onPause();

    Log.i(TAG, "onPause: ");

    setContentView(R.layout.activity_accelerometer);

    if (dataReceiver != null) {
        unregisterReceiver(dataReceiver);
        dataReceiver = null;
    }
    PebbleKit.closeAppOnPebble(getApplicationContext(), SLEEPTRACKER_UUID);
}

@Override
public void onResume() {
    super.onResume();

    Log.i(TAG, "onResume: ");

    final Handler handler = new Handler();

    dataReceiver = new PebbleKit.PebbleDataReceiver(SLEEPTRACKER_UUID) {

        @Override
        public void receiveData(final Context context, final int transactionId, final PebbleDictionary dict) {

            handler.post(new Runnable() {
                @Override
                public void run() {

                    PebbleKit.sendAckToPebble(context, transactionId);

                    final Long cmdValue = dict.getInteger(PP_KEY_CMD);
                    if (cmdValue == null) {
                        return;
                    }

                    if (cmdValue.intValue() == PP_CMD_VECTOR) {

                        // Capture the received vector.
                        final Long xValue = dict.getInteger(PP_KEY_X);
                        if (xValue != null) {
                            vector[VECTOR_INDEX_X] = xValue.intValue();
                        }

                        final Long yValue = dict.getInteger(PP_KEY_Y);
                        if (yValue != null) {
                            vector[VECTOR_INDEX_Y] = yValue.intValue();
                        }

                        final Long zValue = dict.getInteger(PP_KEY_Z);
                        if (zValue != null) {
                            vector[VECTOR_INDEX_Z] = zValue.intValue();
                        }

                        // Update the user interface.
                        updateUI();
                    }
                }
            });
        }
    };

    PebbleKit.registerReceivedDataHandler(this, dataReceiver);
}

public void updateUI() {

    final String x = String.format(Locale.getDefault(), "X: %d", vector[VECTOR_INDEX_X]);
    final String y = String.format(Locale.getDefault(), "Y: %d", vector[VECTOR_INDEX_Y]);
    final String z = String.format(Locale.getDefault(), "Z: %d", vector[VECTOR_INDEX_Z]);

    // Update the numerical fields

    TextView x_axis_tv = (TextView) findViewById(R.id.x_axis_Text);
    x_axis_tv.setText(x);

    TextView y_axis_tv = (TextView) findViewById(R.id.y_axis_Text);
    y_axis_tv.setText(y);

    TextView z_axis_tv = (TextView) findViewById(R.id.z_axis_Text);
    z_axis_tv.setText(z);

    // Update the Plot

    // Remove oldest vector data.
    if (xSeries.size() > SAMPLE_SIZE) {
        xSeries.removeFirst();
        ySeries.removeFirst();
        zSeries.removeFirst();
    }

    // Add the latest vector data.
    xSeries.addLast(null, vector[VECTOR_INDEX_X]);
    ySeries.addLast(null, vector[VECTOR_INDEX_Y]);
    zSeries.addLast(null, vector[VECTOR_INDEX_Z]);

    // Redraw the Plots.
    xyPlot.redraw();
}

}

这是MainActivity：

public class MainActivity extends AppCompatActivity {

/**
 * The {@link android.support.v4.view.PagerAdapter} that will provide
 * fragments for each of the sections. We use a
 * {@link FragmentPagerAdapter} derivative, which will keep every
 * loaded fragment in memory. If this becomes too memory intensive, it
 * may be best to switch to a
 * {@link android.support.v4.app.FragmentStatePagerAdapter}.
 */
SectionsPagerAdapter mSectionsPagerAdapter;

/**
 * The {@link ViewPager} that will host the section contents.
 */
ViewPager mViewPager;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    // Create the adapter that will return a fragment for each of the three
    // primary sections of the activity.
    mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

    // Set up the ViewPager with the sections adapter.
    mViewPager = (ViewPager) findViewById(R.id.pager);
    mViewPager.setAdapter(mSectionsPagerAdapter);

}


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

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}


/**
 * A {@link FragmentPagerAdapter} that returns a fragment corresponding to
 * one of the sections/tabs/pages.
 */
public class SectionsPagerAdapter extends FragmentPagerAdapter {

    public SectionsPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {
        // getItem is called to instantiate the fragment for the given page.

        Fragment fragment =  null;

        if(position == 0){
            fragment = new LogFragment();
        }
        if(position == 1){
            fragment = new AccelerometerFragment();
        }

        return fragment;
    }

    @Override
    public int getCount() {
        // Show 2 total pages.
        return 2;
    }

    @Override
    public CharSequence getPageTitle(int position) {
        Locale l = Locale.getDefault();
        switch (position) {
            case 0:
                return getString(R.string.title_section1).toUpperCase(l);
            case 1:
                return getString(R.string.title_section2).toUpperCase(l);
        }
        return null;
    }
}
}

任何帮助将不胜感激！

Answer 1

如何创建一个膨胀活动布局并在片段上运行活动的片段？

你没有。

这两项活动似乎同时启动，因为应用程序以加速度计活动开始，当按下后退按钮时，它会转到选项卡式活动

这正是你告诉Android要做的事情。您在startActivity()的{{1}}中呼叫onCreate()。正如方法名称所示，AccelerometerFragment启动了一项活动。在这种情况下，您正在开始startActivity()。

将业务逻辑从AccelerometerActivity移至AccelerometerActivity。然后，摆脱AccelerometerFragment中的onCreate()。然后，要么：

完全摆脱AccelerometerFragment或
如果您希望加速度计内容在AccelerometerActivity 和中显示在单独的活动中，请让MainActivity显示自己的AccelerometerActivity实例

Android选项卡式活动：如何创建一个片段来膨胀活动布局并在片段上运行活动？

1 个答案: