我有一个Android应用程序，主要活动非常简单。它只有两个按钮，一个textview和一个edittext字段。我启动了主要活动（我不做任何事情，只是从应用程序抽屉中启动它），然后按主页按钮进入我的主屏幕，转到设置＆gt; appmanager＆gt;正在运行＆gt;缓存的后台进程，我看到我的应用程序比其他缓存的后台进程占用更多的RAM，大约8 MB的RAM。这是正常的吗？为什么它比其他应用程序吃得更多？这是我的代码：
MainActivity：
package com.example.myapp;
import android.app.ActivityManager;
import android.content.ComponentName;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.ActionBarActivity;
import android.telephony.TelephonyManager;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends ActionBarActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
}
ActivityManager am = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
int memoryClass = am.getMemoryClass();
long maxMemory = Runtime.getRuntime().maxMemory();
long totalMemory = Runtime.getRuntime().totalMemory();
Log.i("ilog", "memoryClass: " + memoryClass);
Log.i("ilog", "maxMemory: " + maxMemory);
Log.i("ilog", "totalMemory: " + totalMemory);
}
@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);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
private Button button1;
private Button button2;
private TextView textView1;
private EditText editText1;
private ComponentName cn;
private String disable = "Disable app";
private String enable = "Enable app";
private int enabledState;
private PackageManager pm;
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
button1 = (Button) rootView.findViewById(R.id.button1);
editText1 = (EditText) rootView.findViewById(R.id.editText1);
textView1 = (TextView) rootView.findViewById(R.id.textView1);
button2 = (Button) rootView.findViewById(R.id.button2);
cn = new ComponentName(getActivity(), CallReceiver.class);
pm = getActivity().getPackageManager();
enabledState = pm.getComponentEnabledSetting(cn);
if (enabledState == PackageManager.COMPONENT_ENABLED_STATE_ENABLED) {
button1.setText(disable);
} else {
button1.setText(enable);
}
button1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
enabledState = pm.getComponentEnabledSetting(cn);
if (enabledState == PackageManager.COMPONENT_ENABLED_STATE_ENABLED) {
pm.setComponentEnabledSetting(cn,
PackageManager.COMPONENT_ENABLED_STATE_DISABLED,
PackageManager.DONT_KILL_APP);
button1.setText(enable);
} else {
pm.setComponentEnabledSetting(cn,
PackageManager.COMPONENT_ENABLED_STATE_ENABLED,
PackageManager.DONT_KILL_APP);
button1.setText(disable);
}
}
});
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (editText1.getText().toString().length() > 0) {
Intent callImitateIntent = new Intent(getActivity(), CallReceiver.class);
callImitateIntent.putExtra(TelephonyManager.EXTRA_STATE, TelephonyManager.EXTRA_STATE_RINGING);
callImitateIntent.putExtra(TelephonyManager.EXTRA_INCOMING_NUMBER, editText1.getText().toString());
getActivity().sendBroadcast(callImitateIntent);
} else textView1.setText("Invalid incoming number");
}
});
return rootView;
}
}
@Override
public void onDestroy() {
super.onDestroy();
Intent serviceStopIntent = new Intent(this, WindowService.class);
stopService(serviceStopIntent);
}
}
fragment_main.xml：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.myapp.MainActivity$PlaceholderFragment" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:text="@string/welcome" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView1"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp" />
<EditText
android:id="@+id/editText1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/button1"
android:layout_centerHorizontal="true"
android:layout_marginTop="30dp"
android:maxLength="12"
android:hint="@string/edittext1" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/editText1"
android:layout_centerHorizontal="true"
android:layout_marginTop="30dp"
android:text="@string/button2" />
</RelativeLayout>
所以有人能告诉我为什么它吃了这么多内存？提前谢谢！